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Chemical looping reforming of CH 4 coupled with CO 2 reduction stands out as a promising method for the syngas production. In this process, it is significant to design the oxygen carrier with high reactivity and stability. In this work, a highly efficient oxygen carrier is obtained by physically mixing Metal-modified ZSM-5 with LaFe 0.85 Ni 0.15 O 3 (LFN). The physical and chemical properties of the oxygen carriers are characterized by XRD, Raman, XPS, BET, TEM, NH 3 -TPD, CO 2 -TPD and CH 4 -TPD techniques. It is noted that mesoporous structures are formed over the Ni modified ZSM-5, due to that part of Ni elements replace Al in the silicaluminate framework. The structure change of the ZSM-5 promotes the gas adsorption capacity. CH 4 and CO 2 cannot be adsorbed on the surface of ZSM-5, while Ni-modified ZSM-5 enhances the adsorption capacity for CO 2 to a large degree. Moreover, Ni species are acted as active sites to facilitate the activation of CH 4 and CO 2 during the redox process. The aggregation-redispersion of Ni particles during the reduction-oxidation process inhibits the deactivation of Ni particles, which improves the stability of the oxygen carrier. Among all the obtained samples, LFN/10 wt% Ni-ZSM-5 exhibits the highest yields of syngas (8.38 mmol g−1) and CO (2.42 mmol g−1). [Display omitted] • Modifying ZSM-5 with Ni changed the pore structures and acid sites. • Ni-modified ZSM-5 promoted the adsorption capacity towards CO 2. • The activation of CH 4 and CO 2 could be improved over Ni-modified ZSM-5. • Ni particles maintained active by aggregation-redispersion under redox atmospheres. • LFN/10 wt% Ni-ZSM-5 exhibited high stability either in the activity or structure. [ABSTRACT FROM AUTHOR]

In this study, multi-walled carbon nanotubes (MWCNTs) were synthesized using the arc discharge method, and gold (Au) , and Au@MWCNT nanoparticles (NPs) were obtained via a rapid and cost-effective chemical reduction method. The performance of these catalysts in ethylene glycol (EG) fuel cells was investigated. According to the Transmission Electron Microscope (TEM) results, the Au particle size was determined to be 3.89 nm, and the MWCNT diameter was found to be 8.21 nm. For EG oxidation, current densities of 33.28 mA/cm2 for Au NPs and 171.28 mA/cm2 for Au@MWCNT NPs were obtained. This result demonstrates that the MWCNT support increased the electrocatalytic activity by a factor of 5.14. Long-term stability tests showed that the MWCNT support exhibited more stable and consistent characteristics and improved CO tolerance. Electrochemical Impedance Spectroscopy (EIS) testing revealed that the MWCNT-supported structure significantly enhanced charge transfer. These findings contribute significantly to the literature by demonstrating the potential for cost-effective production of carbon supported Au NPs, and their application in fuel cells. • MWCNT production using arc-discharge method. • Preparation of Au and Au@MWCNT catalysts and their use in ethylene glycol oxidation studies. • Au@MWCNT exhibits superior electrocatalytic activity towards ethylene glycol oxidation. • Synthesis of more stable catalyst for ethylene glycol oxidation. • Anode catalyst showing high potential for fuel cell applications. [ABSTRACT FROM AUTHOR]

Electrocatalysts, which are important in increasing the efficiency of fuel cells, still have disadvantages such as low stability and high cost. To overcome these disadvantages, research on the synthesis of low-cost nanoparticle (NP) catalysts has been carried out. In this study, a new approach to develop a low-cost, high electrocatalytic activity and more stable catalyst was realized. In this context; kaolin ((Al 2 O 3 (SiO 2) 2 (H 2 O) 2)) and zinc oxide (ZnO) supported palladium-copper (PdCl 2 –CuCl 2) nanostructures were synthesized by chemical reduction technique. The particle sizes of the synthesized PdCu@kaolin and PdCu@ZnO NPs were found to be 12.02 nm and 23.02 nm, respectively, according to the Debye Scherrer formula. The PdCu@kaolin and PdCu@ZnO NPs obtained within the scope of the study were also used in the anodic oxidation of methanol (CH₃OH), a one-carbon organic compound. According to the results obtained, the current density for methanol oxidation peaks of PdCu@kaolin and PdCu@ZnO NPs were found to be 27.77 mA cm−2 and 41.52 mA cm−2, respectively. It was observed that the ZnO-supported nanoparticles provided 1.49 times higher electrocatalytic activity compared to the other one. The 500-cycle results showed that the ZnO-supported catalyst exhibited a continuously increasing current density. The tests also proved that the catalysts are diffusion-controlled systems and have high stability. Within the scope of the study, ZnO and Kaolin support not only decreased the cost of the catalyst but also significantly affected the electrocatalytic activity, offering better results than the commercial Pd/C catalyst. Cost-effective ceramic structures such as kaolin and ZnO were crucial to show high stability and electroactive behavior close to the literature. The current study has performed an important contribution to the literature on the use of ceramic materials in electrochemistry. • Synthesis of PdCu@kaolin and PdCu@ZnO NPs by chemical reduction. • High electrocatalytic activity of PdCu@kaolin and PdCu@ZnO NPs against methanol oxidation. • Cost-effective and highly stable catalysts. • Efficient anode catalysts for methanol fuel cells. [ABSTRACT FROM AUTHOR]

Developing effective transition metal catalysts that can replace precious metal-based catalysts for hydrogen generation from the hydrolysis of chemical hydride has attracted extensive interest. This study focuses on synthesizing cobalt phospho-boride (CoPB) within a metal-organic framework (MOF) framework using hydrothermal and chemical reduction methodologies. Incorporating boron and phosphorous into Co-MOF enhances the hydrogen generation rate, reaching 1.8 L/min/g and 3.6 L/min/g for CoB-MOF and CoPB-MOF, respectively, during NaBH 4 hydrolysis. Along with the nanostructured morphology of MOF, the electron modulation around Co-sites due to the presence of P and B creates a synergic effect to produce this high H 2 generation rate and very low activation energy of 20.7 kJ/mol. The kinetic studies on NaBH 4 hydrolysis reaction revealed zero-order kinetics with respect to NaBH 4 concentration for CoPB-MOF, where porous morphology renders facile movement of BH 4 − ions to the active sites. The heat treatment at 773 K in the N 2 atmosphere did not show any significant fall in the activity of CoPB-MOF, thus showcasing its robust nature. Moreover, the present catalyst also displayed recycling behavior with no signs of deactivation. [Display omitted] • Co–B and CoPB MOFs were synthesized by the hydrothermal method. • The MOFs were used as catalysts for the Hydrolysis of NaBH 4 for Hydrogen production. • CoPB MOF exhibited an enhanced H 2 generation rate with low activation energy. • The enhanced activity is attributed to the morphology and the incorporation of boron and phosphor. [ABSTRACT FROM AUTHOR]

Industrial biotechnology and biocatalysis can provide very effective synthetic tools to increase the sustainability of the production of fine chemicals, especially flavour and fragrance (F&F) ingredients, the market demand of which has been constantly increasing in the last years. One of the most important transformations in F&F chemistry is the reduction of C C bonds, typically carried out with metal-catalysed hydrogenations or hydride-based reagents. Its biocatalytic counterpart is a competitive alternative, showcasing a range of advantages such as excellent chemo-, regio- and stereoselectivity, ease of implementation, mild reaction conditions and modest environmental impact. In the present review, the application of biocatalysed alkene reductions (from microbial fermentations with wild-type strains to engineered isolated ene-reductase enzymes) to synthetic processes useful for the F&F industry will be described, highlighting not only the exquisite stereoselectivity achieved, but also the overall improvement when chirality is not involved. Multi-enzymatic cascades involving C C bioreductions are also examined, which allow much greater chemical complexity to be built in one-pot biocatalytic systems. [Display omitted] • C C reduction is a key transformation in the synthesis of flavours and fragrances. • Biocatalytic alternatives involve ene-reductases or microorganisms habouring them. • Many examples of industrially relevant molecules are provided and discussed. • Multi-enzymatic systems involving C C bioreductions are also examined. [ABSTRACT FROM AUTHOR]

The advancement of electrocatalysts exhibiting outstanding performance in the oxygen evolution reaction (OER), crucial for hydrogen production, holds immense significance in addressing energy shortages and mitigating environmental pollution. In this study, a novel approach to synthesizing Co-MOF (Metal-Organic Framework) directly immobilized onto a Ni foam substrate through hydrothermal synthesis is presented. In contrast to conventional methods employing powder-based synthesis with binders, our direct attachment method offers a unique and efficient means of creating robust Co-MOF at Ni foam (Co-MOF@NF) hybrid catalysts. Subsequently, a chemical reduction approach utilizing sodium borohydride was employed to introduce surface modification into the Co-MOF structure. The resulting material, sodium borohydride treated Co-MOF@NF (Red. 1 h Co-MOF@NF), exhibited a remarkable enhancement in OER activity compared to the pristine Co-MOF@NF sample. Notably, Red.1 h Co-MOF@NF demonstrated a substantially reduced overpotential of 235 mV to achieve a current density of 10 mA cm⁻2, in contrast to the 300 mV overpotential required by the pristine Co-MOF@NF under the same conditions. Furthermore, the Red.1 h Co-MOF@NF catalyst displayed exceptional stability, sustaining a current density of 50 mA cm⁻2 for over 48 h, highlighting its promising potential for practical applications. The synergistic effects of direct hydrothermal attachment, surface modification, and improved OER performance make this study a significant contribution to the advancement of efficient and stable electrocatalysts for energy conversion applications. [Display omitted] • The self-supported Co-MOF dodecahedrons on Ni foam were synthesized. • Surface modified Red. 1 h Co-MOF@NF heterostructure was achieved via NaBH 4 reduction. • Surface modification introduces additional active sites on the catalyst's surface leading to improved OER performance. • The Red. 1 h Co-MOF@NF demonstrates remarkable catalytic performance and stability for the OER. [ABSTRACT FROM AUTHOR]

This study aims to shed light on the elemental and mineralogical mechanisms controlling the storage and flow performances of tight conglomerates. This is achieved through the application of Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive Spectrometer (EDS), TESCAN Integrated Mineral Analyzer (TIMA), and geophysical logging data. The findings suggest that augmenting the Mg and CaO content in silicates can markedly enhance the storage capacity of tight conglomerates within the Upper Wuerhe Formation. Chlorite exerts a positive influence on the evolution of reservoir porosity, whereas an escalation in Na content does not foster the development of reservoirs with superior physical attributes. A reduction in the chemical index of alteration (CIA) facilitates the creation of a more expansive pore space, while an elevation in the index of component variation (ICV) augments porosity and diminishes mud content, albeit it may also curtail oil content. It is pertinent to note that an increase in ICV is not invariably advantageous. The emergence of orthoclase results in a decrease in porosity and an enhancement in permeability, whereas the progression of kaolinite adversely affects reservoir porosity. The conclusion may yield significant insights for hydrocarbon exploration in these regions, as well as in reservoirs exhibiting analogous lithologies. • The porosity of the conglomerate increases with Mg and the chlorite content. • Element and mineral properties determine the physical properties. • Geophysical and geochemical data can be integrated to study pores. [ABSTRACT FROM AUTHOR]

For a chemical looping hydrogen generation system, the set of input gas flow rate needed to be adjusted on the reactivity of oxygen carriers, in order to guarantee gas conversion and to obtain higher hydrogen purity. However, the oxygen carriers often decayed upon repeated cycles, leading to pressing need for dynamic alignment between oxygen carrier reactivity and process parameters. Herein, we propose a reaction optimization control method based on machine learning methods that can establish a real-time matching system between the flow rate of input gas and the reactivity of oxygen carriers. The results show that the prediction of hydrogen yield from oxygen carriers when using the optimized Gradient Boosting Decision Tree model is in general agreement with the experimental results (R2 = 0.87, MAE = 0.49). Based on high-precision prediction results, the method is capable of realizing the input gas flow based on the predicted hydrogen production in real time in less than 10s and realizing digital twin with the expansion of the dataset. We envision that the proposed control method can accelerate the industrial application of chemical looping hydrogen generation by predicting accurate operating parameters that can reduce fuel costs and guarantee reactivity of oxygen carriers. • Interpretable relationship between reaction variables and cyclic hydrogen production through machine learning modeling. • Hyperparameter optimization of machine learning models to solve overfitting problems. • The predicted hydrogen production for the new input oxygen carriers is in general agreement with the experimental results. • Digital twin system solves the problem of unstable reduction depth in chemical looping hydrogen production. [ABSTRACT FROM AUTHOR]

The air quality in China has improved significantly in the last decade and, correspondingly, the characteristics of PM 2.5 have also changed. We studied the interannual variation of PM 2.5 in Chengdu, one of the most heavily polluted megacities in southwest China, during the most polluted season (winter). Our results show that the mass concentrations of PM 2.5 decreased significantly year-by-year, from 195.8 ± 91.0 µg/m3 in winter 2016 to 96.1 ± 39.3 µg/m3 in winter 2020. The mass concentrations of organic matter (OM), SO 4 2−, NH 4 + and NO 3 − decreased by 49.6%, 57.1%, 49.7% and 28.7%, respectively. The differential reduction in the concentrations of chemical components increased the contributions from secondary organic carbon and NO 3 − and there was a larger contribution from mobile sources. The contribution of OM and NO 3 − not only increased with increasing levels of pollution, but also increased year-by-year at the same level of pollution. Four sources of PM 2.5 were identified: combustion sources, vehicular emissions, dust and secondary aerosols. Secondary aerosols made the highest contribution and increased year-by-year, from 40.6% in winter 2016 to 46.3% in winter 2020. By contrast, the contribution from combustion sources decreased from 14.4% to 8.7%. Our results show the effectiveness of earlier pollution reduction policies and emphasizes that priority should be given to key pollutants (e.g., OM and NO 3 −) and sources (secondary aerosols and vehicular emissions) in future policies for the reduction of pollution in Chengdu during the winter months. [ABSTRACT FROM AUTHOR]

Hydrogen generated in severe accidental conditions poses a threat to nuclear containment once it exceeds the flammability limit in the air. A passive Autocatalytic Recombiner (PAR) device is one of the best options to tackle this scenario. In view of this, we have developed a novel breed of bimetallic Pt–Pd nano-catalysts supported over cordierite by a chemical reduction route. Pt–Pd particles with dimensions ∼4.5–11.5 nm were found to be in a metallic state and amorphous in nature. They were assessed for H 2 and O 2 recombination reactions and found to be catalytically active for the same. Their activity was also established in the presence of various probable contaminants viz. CO, CO 2 , CH 4 , relative humidity, and catalyst wetness. • Pt + Pd bimetallic catalyst was developed for hydrogen mitigation under severe accident conditions. • Ceramic support was used for enhanced properties of the catalyst. • Catalyst exhibits unaltered catalytic activity in presence of various poisons. • Catalyst retains its activity in presence of CO for wider range of concentrations. • Activation energy calculated and compared to earlier reported catalyst. [ABSTRACT FROM AUTHOR]

Materials space-tectonics (MST) methodology is a powerful strategy to design catalytic materials synthesis to overcome the limitation of monotonous pore geometries and develop functional structures with surface-specific functions. Based on the MST, herein, carbon nanohorns (CNH) as "spacers" inserted into three-dimensional (3D) nitrogen-doped graphene aerogel (NG) anchoring Pd nanocrystalline (Pd/CNH@NG) was constructed through a facile hydrothermal approach and wet chemical reduction method without surfactant and employed as electrocatalyst for ethanol oxidation reaction (EOR). The introduction of CNH can provide important mesopore and macropore characters and generate more active sites to anchor Pd nanocrystalline on the basis of unique internal and interstitial nanopore structures, high surface area and conductive graphitic structure, then enhancing the electrocatalytic efficiency, stability and poison tolerance of catalysts. Meanwhile, the role of CNH doped NG also includes accelerating the reaction of the intermediate (CH 3 CO ads) manufactured on the Pd-based aerogels surface with adsorbed hydroxyl (OH ads) due to coordination effect from Pyridinic-nitrogen and pyrrolic-nitrogen species. The electrochemical results reveal that the specific and mass activities of the obtained Pd/CNH@NG-2 aerogel (the mass ratio of graphene oxide and CNH is 1:3) are 1.38 and 2.86 times higher than those of the commercial Pd/C for EOR. Simultaneously, the current density of Pd/CNH@NG-2 still maintains 70 % after 500 cycles of complete CV, but commercial Pd/C only maintains 22.6 % of the initial activity. The synthesis of Pd/CNH@NG not only offers a porous three-dimensional aerogel for the EOR but also optimizes a facile strategy to fabricate superior supports for promoting the commercialization of DEFCs. [Display omitted] • The Pd/CNH@NG was fabricated by facile hydrothermal approach and wet chemical reduction method without surfactant. • The important mesopore and macropore characters and more active sites of Pd/CNH@NG are induced by CNH-incorporating. • The Pd/CNH@NG reveals prominent electrocatalytic activity, stability and resistance to poisoning. [ABSTRACT FROM AUTHOR]

In this study, the effects of silane on bimetallic nanoparticles modified with reduced graphene oxide were investigated for direct methanol fuel cells. In this direction, PtCo bimetallic nanoparticles were produced using the chemical reduction method. PtCo@NH 2 -rGO catalyst was obtained by combining these nanoparticles on 3-Aminopropyltriethoxysilane (APTES) modified reduced Graphene Oxide (rGO). Characterization of the PtCo@NH 2 -rGO catalyst was performed by X-Ray Diffractometry (XRD), Fourier Transform Infrared (FTIR), and UV–Visible Spectrophotometer (UV-VIS). The methanol oxidation performances of the obtained catalysts were investigated in order to observe the electrochemical effect of NH 2 -rGO supporting agent on unsupported PtCo and supported PtCo (PtCo@NH 2 -rGO) catalysts. The PtCo@NH 2 -rGO electrocatalyst showed a high oxidation peak current density (86.02 mA/cm2) for the anodic portion of the direct methanol fuel cell. This result shows the high performance of the NH 2 -rGO supported catalyst for direct methanol fuel cells. The resulting catalyst gives promise for potential direct fuel cell applications. • Silane-modified graphene oxide (NH 2 -rGO) synthesized using APTES as supporting agents. • Highly dispersed PtCo nanoparticles on NH 2 -rGO support. • Superior catalytic performance of PtCo@NH 2 -rGO towards methanol oxidation reaction. • High stability and internediate tolerance of PtCo@NH 2 -rGO for methanol oxidation. [ABSTRACT FROM AUTHOR]

The transition-metals carbon catalysts belong to intensively studied alternatives to the Pt-based catalysts promoting the oxygen reduction reaction (ORR) in electrochemical fuel cells (FCs). Commonly studied Fe,Co–N–C composites are usually obtained through pyrolysis and used as such or after a chemical post-treatment with an oxidizing agent. This treatment is applied to remove inactive metal species, thus, promoting the electrochemical activity. The impact of an oxidizing agent is poorly addressed in the literature, while its nature may negatively affect the catalyst's performance. Herein we report the first comparative study on the effect of post-treatment with the most common oxidizing agents such as HCl, HNO 3 , H 2 SO 4 and H 2 O 2 , on the structural and electrochemical properties of the Fe,Co–N–C catalyst. The catalyst is made by pyrolysis of the Co,Zn-ZIF metal-organic framework enriched with iron and nitrogen. Its structure was observed withstanding the action of mineral acids but suffers from hydrogen peroxide. The treatment with either nitric or chloric acid may improve the electrochemical performance up to 4%, while other agents decrease that by 6% and slow down the ORR rate. These findings are useful for the careful design of post-treatment procedures for carbon catalysts. • The Fe,Co–N–C carbon-based catalyst was obtained from Fe,Co-ZIF-8 MOF via pyrolysis at 700 °C in an inert atmosphere. • The Fe,Co–N–C catalyst was treated with four oxidizing agents - chloric, nitric and sulfuric acids, and hydrogen peroxide. • Structural and compositional changes were assessed with multi-technique characterization of the catalysts. • The catalysts treated with nitric and chloric acids demonstrated improved performance for ORR in an acidic medium. [ABSTRACT FROM AUTHOR]

The development of high-efficient and low-cost catalysts is crucial for promoting KBH 4 hydrolysis to produce hydrogen. Herein, ZIF-67 supported cobalt-molybdenum-nickel based boride (Co–Mo–Ni–B/ZIF-67) nanocomposites with dandelion-like morphology were designed as catalysts of KBH 4 hydrolysis reaction and were synthesized via the chemical reduction process. Moreover, the element ratio and the loading amount of Co–Mo–Ni–B were optimized, and effects of KBH 4 concentration, KOH concentration, and reaction temperature on catalytic performances were studied. As expected, ZIF-67 substrate avoids the agglomeration of amorphous Co–Mo–Ni–B, and the synergy between ZIF-67 and uniformly dispersed Co–Mo–Ni–B active substances accelerates hydrogen generation rate. As a result, the maximum hydrogen generation rate of 17400 mL min−1 g−1 is achieved with the optimized KOH concentration of 10% and KBH 4 concentration of 6% at the reaction temperature of 30 °C. In addition, Co–Mo–Ni–B/ZIF-67 exhibits moderate durability performance with a cyclic retention rate of 51.9 % after five cycles. This dandelion-like structure design provides an idea for the development of efficient catalyst for hydrolysis of borohydrides. [Display omitted] • Co–Mo–Ni–B/ZIF-67 is prepared as catalysts of KBH 4 hydrolysis reaction. • The dandelion-like structure of Co–Mo–Ni–B/ZIF-67 exhibits excellent catalytic performance. • Co–Mo–Ni–B/ZIF-67 with optimized composition displays the hydrogen generation rate of 17400 mL min−1 g−1 at 30 °C. • ZIF-67 substrate avoids the agglomeration of amorphous Co–Mo–Ni–B. [ABSTRACT FROM AUTHOR]

The process of hydrolysis of sodium borohydride is a new and clean method for the production of hydrogen. In this study, cobalt nanoparticles were synthesized by the mechanochemical and chemical reduction methods, and their catalytic performance was compared. The effect of using different cobalt precursors and reducing agents was investigated for the sample prepared via the chemical reduction method. The results showed that the cobalt catalysts synthesized through the chemical reduction method possessed better catalytic performance. Also, the sample prepared using cobalt nitrate and sodium borohydride had a higher hydrogen generation rate (HGR), which was equal to 3272.7 ml min−1g−1. The kinetics of the cobalt catalyst in the process have also been investigated, revealing that the rate of hydrogen production is dependent on the concentrations of sodium borohydride and sodium hydroxide, the catalyst dosage, and the process temperature. The crystal size of this catalyst was 21.6 nm with spherical agglomerated particles. The BET area of the best sample and its activation energy was equal to 11.18 m2g-1 and 22.3 kJmol-1, respectively. This catalyst was also stable in successive cycles. [Display omitted] • Cobalt catalysts were synthesized via the mechanochemical and chemical reduction methods. • The catalytic performance of the cobalt catalyst in the hydrolysis of NaBH 4 was high. • The hydrogen generation rate of the Co–B catalyst was 3272.7 mLmin−1g−1 at 30 °C. • The activation energy of the Co–B catalyst is lower compared to that of other cobalt-based catalysts. [ABSTRACT FROM AUTHOR]

This study aims to enhance the photocatalytic activity of graphitic carbon nitride (g-C 3 N 4) for visible light H 2 evolution and pollutant degradation by creating Ni 0.8 Co 0.2 /Zn 0.8 Cd 0.2 S (ZCS)/g-C 3 N 4 (CN) ternary nano-photocatalyst. Ni 0.8 Co 0.2 /ZCS/CN is produced via chemical reduction and hydrothermal methods. The morphology, structural characteristics, and photocatalytic characteristics of the nano-photocatalyst were assessed by FE-SEM, EDS, HR-TEM, BET, XRD, FTIR, UV–Vis DRS, PL, EIS and UV–Vis spectroscopy. Photocatalytic water splitting and degradation of methylene blue (MB, C 16 H 18 N 3 SCl) in an aqueous solution were carried out under an LED lamp (100 W, 400 nm–700 nm) irradiation for 4 and 3 h, respectively. Considering the test results, the H 2 evolution rate of Ni 0.8 Co 0.2 /ZCS/CN was measured at 1980 μmol/g.h, which demonstrates an astonishing 1980-fold increase in comparison with g-C 3 N 4. Additionally, the degradation efficiency of MB equals 85 % within 3 h. The improved catalytic performance of Ni 0.8 Co 0.2 /ZCS/CN is primarily attributed to forming of a heterojunction between Ni 0.8 Co 0.2 /ZCS and g-C 3 N 4 nanosheets, facilitating the separation and migration of photoexcited charge carriers. Consequently, this ternary nano-photocatalyst can be a potential photocatalytic material for H 2 evolution under visible light. This research offers guidelines for developing novel heterojunction catalysts that are highly efficient and environmentally friendly. • Ni 0.8 Co 0.2 /Zn 0.8 Cd 0.2 S/g-C 3 N 4 is produced via chemical reduction and hydrothermal methods. • Photocatalytic water splitting and degradation of MB were carried out under visible light. • Ni 0.8 Co 0.2 /Zn 0.8 Cd 0.2 S/g-C 3 N 4 exhibits a significant enhancement in H 2 evolution and MB degradation compared to g-C 3 N 4. • Ni 0.8 Co 0.2 /Zn 0.8 Cd 0.2 S/g-C 3 N 4 exhibited durability for 16 h. [ABSTRACT FROM AUTHOR]

Hierarchical porous nanostructure alumina ceramics (HP-Al 2 O 3) were prepared through a novel approach involving polymer-assisted freeze-drying and subsequent calcination. The resulting material exhibits interconnected micro-meso-macro pores, distinguishing it from traditional Al 2 O 3 nanoparticles (Al 2 O 3 -Nps) prepared without freeze-drying. By manipulating freeze-drying precursors and calcination temperatures, we tailor the morphology and structure of HP-Al 2 O 3. Notably, the HP-Al 2 O 3 demonstrates a remarkable 5.3-fold increase in adsorption efficiency for Congo red compared to Al 2 O 3 -Nps, attributed to its significantly larger specific surface area. The HP-Al 2 O 3 is a versatile platform for building multi-functional composites, proved by immobilizing silver nanoparticles (AgNps) and graphitized carbonitride (g-C 3 N 4) through chemical reduction and gas-solid reaction methods, respectively. When employed for the reduction of 4-nitrophenol and the degradation of Rhodamine B, Ag/HP-Al 2 O 3 and g-C 3 N 4 /HP-Al 2 O 3 display approximately 2.5 and 2.4 times higher reaction rate constants compared to Ag/Al 2 O 3 -Nps and g-C 3 N 4 /Al 2 O 3 -Nps. This enhanced catalytic performance is attributed to several key factors: the 3D porous framework of the HP-Al 2 O 3 facilitates efficient catalyst immobilization, the microporous and mesoporous nature increases the active site and specific surface area, and the hierarchical porous structure enhances mass diffusion and light capture. Moreover, the self-supporting nature of the HP-Al 2 O 3 simplifies separation and recovery from reaction solutions. With the integration of its hierarchical porous structure and commendable recovery properties, HP-Al 2 O 3 emerges as a promising candidate for various functional applications, particularly in catalysis. [ABSTRACT FROM AUTHOR]

Developing the bifunctional oxygen carrier with excellent oxygen mobility and catalytic activity is the key to chemical looping combustion coupled CO 2 hydrogenation to light olefins. In this study, a series of K/La y Co x Fe 1-x O 3 (x = 0, 0.2, 0.4, 0.6, y = 0.2, 0.4, 0.8) with oxygen vacancy-active metal dual active centers were constructed by the Co doping-La defect synergistic strategy to evaluate the oxygen release and catalytic performance. The results indicated that K/La 0.4 Co 0.4 Fe 0.6 O 3 had high oxygen mobility, and its reduced state can be directly used for CO 2 hydrogenation to light olefins (C 2 =-C 4 =). The selectivity of C 2 =-C 4 = was close to 30%, and the conversion rate of CO 2 was 36%. Combined with various characterizations, the synergy of Co doping and La defects increased the oxygen vacancy and promoted the exsolved CoFe alloy under the reduction induction of chemical looping combustion. In situ DRIFTS reveals the dynamic equilibrium of the Formate-Methoxy mechanism and RWGS-FTS pathway. Oxygen vacancies are found to enhance the conversion of CO 2 via the formate pathway, while metal active phases alter the product distribution by changing the evolution of intermediates. The Co 7 Fe 3 and oxygen vacancy on K/La 0.4 Co 0.4 Fe 0.6 O 3 promotes the formation of CH x ∗ and C–C coupling through various intermediates, improving the selectivity of light olefins. • K/La 0.4 Co 0.4 Fe 0.6 O 3 exhibits "oxygen-catalysis" bifunctional properties. • Co-doping and La-defects increase oxygen vacancies and promote metal exsolution. • The oxygen vacancies and the exsolved metal provide dual active centers. • The reaction underwent a dual path through multiple intermediates. [ABSTRACT FROM AUTHOR]

This paper aims to provide a holistic analysis of the role of hydrogen for achieving greenhouse gas neutrality in Germany. For that purpose, we apply an integrated energy system model which includes all demand sectors of the German energy system and optimizes the transformation pathway from today's energy system to a future cost-optimal energy system. We show that 412 TWh of hydrogen are needed in the year 2045, mostly in the industry and transport sector. Particularly, the use of about 267 TWh of hydrogen in industry is essential as there are no cost-effective alternatives for the required emission reduction in the chemical industry or in steel production. Furthermore, we illustrate that the German hydrogen supply in the year 2045 requires both an expansion of domestic electrolyzer capacity to 71 GW H2 and hydrogen imports from other European countries and Northern Africa of about 196 TWh. Moreover, flexible operation of electrolyzers is cost-optimal and crucial for balancing the intermittent nature of volatile renewable energy sources. Additionally, a conducted sensitivity analysis shows that full domestic hydrogen supply in Germany is possible but requires an electrolyzer capacity of 111 GW H2. • 412 TWh of hydrogen demand in a greenhouse gas neutral Germany in the year 2045. • Hydrogen usage is crucial for defossilization of chemical and steel industry. • 47% of hydrogen is imported from other European countries and Northern Africa. • 71 GW H2 of electrolyzer capacity in Germany with flexible operation. • 35 TWh of hydrogen storage in salt caverns for security of supply. [ABSTRACT FROM AUTHOR]

• This review summarized the application of low-temperature plasma for the conservation of cultural heritage objects. • The principle and features of different low-temperature plasma setups are presented. • Different plasma processing including plasma chemical reduction, deposition, decontamination, deacidification etc. are presented. As the representative traces left by human beings in social activities, many cultural heritage objects are considered to have important historical, artistic, and scientific values. However, they usually suffer from various aspects of deterioration such as corrosion, stains derived from different sources (soot, dust, microorganisms, etc.), weakness, color change, etc. The most important goal for conservators is to prolong the existence of artifacts far beyond their natural lifespan, on the premise that minimal changes have been made to the originality of the objects or artworks. In this review, the authors focus on the application of low-temperature plasma for the conservation of cultural heritage objects. At the beginning of this review, the principle and features of different low-temperature plasma setups are presented. Then, the review can be divided into several groups based on the treatment type, including plasma chemical reduction of metallic artifacts, protective coatings (polymer coatings, diamond-like Carbon (DLC) coatings, and SiO 2 protective layers), the mechanism and effect of microorganism inactivation, plasma deacidification of paper relics, enhancement of physical/chemical properties, and cleaning of painting. [Display omitted] [ABSTRACT FROM AUTHOR]

Platinum-based alloy materials as effective cocatalysts in improving the performance of photocatalytic H 2 production have raised great interest. Herein, a facile strategy of chemical reduction is established to synthesize bimetallic PtNi nanoparticles on 2D g-C 3 N 4 nanosheets with excellent photocatalytic activity. The addition of PtNi nanoparticles can provide new H+ reduction sites and increase more active sites of the material. The synergistic effect between PtNi alloy nanoparticles and 2D g-C 3 N 4 nanosheets can regulate electronic structure, narrow the band, accelerate charge transfer efficiency and inhabit the recombination of photo-induced electron (e−) and hole pairs (h+), contributing to the improvement of hydrogen evolution activity. The optimal hydrogen evolution rate of Pt 0.6 Ni 0.4 /CN shows higher hydrogen evolution rate (9528 μmol·g−1·h−1), which is 13.1 times than that of pure g-C 3 N 4 nanosheets. Besides, a possible mechanism of photocatalytic hydrogen generation has been brought up according to a series of physical and chemical characterization. This work also provides a potential idea of developing cocatalysts integrating metal alloys with 2D g-C 3 N 4 nanosheets for promoting photocatalytic hydrogen evolution. The integration of bimetallic PtNi nanoparticles and g-CN can inhabit the recombination of photo-induced electron (e−) and hole pairs (h+), contributing to promoting hydrogen evolution activity. [Display omitted] • Pt x Ni 1-x /CN catalysts were synthesized by a facile method of chemical reduction. • The synergistic effect of PdNi alloy could accelerate charge transfer efficiency. • The Pt 0.6 Ni 0.4 /CN showed the highest H 2 generation activity. • A possible mechanism of photocatalytic hydrogen production was proposed. [ABSTRACT FROM AUTHOR]

Hydrogen safety is a primary obstacle to the widespread use of hydrogen energy, and the risk of hydrogen utilization can be avoided by eliminating unnecessary hydrogen immediately. Here we report a new kind of hydrogen elimination catalyst based on ZrVFe hydrogen storage alloy supported Pt. The chemical reduction temperature and the Pt loading have a great influence on the hydrogen elimination performance. When the reduction temperature is 60 °C and the Pt loading is 2 wt%, the ZrVFe/Pt catalyst exhibits excellent hydrogen elimination ability at 2–20 vol% hydrogen concentration, especially the efficiency of hydrogen elimination at 20 vol% hydrogen concentration is as high as 99%. The hydrogen adsorption capacity of the ZrVFe/Pt catalyst was 13 times higher than that of the commonly used metal carrier FeCrAl/Pt catalyst. This work paves a new direction for the design and on-going development of hydrogen elimination catalyst for hydrogen energy applications. [Display omitted] • ZrVFe hydrogen storage alloy is used as a catalyst carrier for hydrogen elimination. • ZrVFe/Pt catalysts exhibit excellent hydrogen elimination performance at 2–20 vol% hydrogen concentration range. • The catalyst achieves 99% hydrogen conversion at 450 °C. • The hydrogen absorption reaction promotes hydrogen-oxygen complexation, thus increasing the hydrogen elimination capacity. [ABSTRACT FROM AUTHOR]

Hydroxytyrosol (HT) is a novel functional pharmaceutical or food ingredient that can be prepared using tyrosinase (TYR) as the catalyst. In this study, cross-linked agarose resin (AG-NTA-Ni2+) was selected as the carrier for the one-step immobilization and purification of the enzyme via specific adsorption of the His-tag on the protein and metal ions on the carrier particles. The immobilized TYR exhibited excellent thermal and pH stabilities and retained 82.3% of its relative activity after seven cycles. Using different reduction methods, immobilized TYR was used as a catalyst to synthesize HT via the controlled oxidation of tyrosol. The enzymatic cascade reaction of co-immobilized TYR and glucose dehydrogenase (GDH) as a biocatalyst served as a bioreduction method with an HT yield of 88%. For the chemical reduction using ascorbic acid (AA) as the reducing agent, an 80% HT yield was achieved. These results indicate that the immobilization method, which relies on the specific coordination between transition metal ions and certain protein amino acids, is a potential strategy for the effective co-immobilization of TYR and GDH. The proposed affinity co-immobilization technique is among the potential strategies for the efficient production of HT. [Display omitted] • Co-immobilization of tyrosinase and glucose dehydrogenase for efficient synthesis of hydroxytyrosol (HT). • Affinity adsorption endows immobilized bienzyme with satisfactory activity and stability. • Conversion of HT prepared by multi-enzyme cascade reduction outperforms chemical reduction process. [ABSTRACT FROM AUTHOR]

Electrochemical ammonia synthesis from N 2 under mild condition is considered a promising strategy to store energy produced by renewable sources, but it is affected by the lack of efficient catalysts for nitrogen reduction. In this work Fe-based nanoparticles with different morphology are deposited on carbon cloth via drop-casting and chemical reduction. The catalyst activity has been evaluated by cyclic voltammetry and chronoamperometry, using a 0.01 M phosphate buffered electrolyte (PBS). The produced ammonia has been determined through the indophenol method. As effective strategy to improve the catalytic activity, the morphology and particle size have been optimized and an electrochemical activation procedure has been implemented. Activation increases the available active sites and is related to higher amount of oxygen vacancies and Fe+2/Fe+3 ratio. Catalysts with optimized morphology produce ammonia at −0.35 V vs RHE with yield of 26.44 μg mg cat −1h−1 and Faradaic efficiency of 20.4%, more than five times higher than without activation. [Display omitted] • Fe-based NPs are deposited by drop casting and chemical reduction on C-cloth substrates. • Particles morphology has been optimized. • The catalytic activity for Nitrogen electroreduction reaction was investigated. • A crucial role is played by the oxygen vacancies and by the Fe+2/Fe+3 ratio. • The ammonia yield with the optimized catalyst was 5 times higher than without optimization. [ABSTRACT FROM AUTHOR]

Recently, non-magnetic carbon-based composite has been regarded as one of the most promising electromagnetic wave absorbing (EMWA) materials. How to realize high EMWA performances at ultra-thin matching thickness is a hot research topic. In this study, a strategy to construct three-dimensional (3D) porous BaTiO 3 @reduced graphene oxide (BTO@rGO) composite aerogel was performed by successively hydrothermal process, chemical reduction and freeze-drying. The results show that defect-rich BTO nanoparticles are dispersedly immobilized into 3D conductive rGO framework by a form of Ba2+ bonding to rGO, enhancing conduction loss and dipole polarization, which contributes to enhanced EMWA performance. As a result, a minimum reflection loss of −50.49 dB with a matching thickness of only 1.46 mm, along with an effective absorption bandwidth of 3.74 GHz (13.07 GHz–16.81 GHz) with a matching thickness of only 1.39 mm, is achieved for 3D porous BTO@rGO composite aerogel. Therefore, this study paves a way for designing and preparing excellent non-magnetic EMWA materials at ultra-thin matching thickness. [ABSTRACT FROM AUTHOR]

• Recent progresses in reductive debromination of polybrominated diphenyl ethers are reviewed. • Photolysis, photo-, electro-, chemical catalysis, and mechanochemical method are compared. • Information on the thermodynamics and kinetics of PBDEs degradation are provided. • The degradation mechanisms in various systems are summarized. • Complete debromination occurs easily with active hydrogen atoms as reactive species. Polybrominated diphenyl ethers (PBDEs) are widely used as brominated flame retardants, which had attracted amounts of attention due to their harmful characteristics of high toxicity, environmental persistence and potential bioaccumulation. Many chemical reductive debromination technologies have been developed for the debromination of PBDEs, including photolysis, photocatalysis, electrocatalysis, zero-valent metal reduction, chemically catalytic reduction and mechanochemical method. This review aims to provide information about the degradation thermodynamics and kinetics of PBDEs and summarize the degradation mechanisms in various systems. According to the comparative analysis, the rapid debromination to generate bromine-free products in an electron-transfer process, of which photocatalysis is a representative one, is found to be relatively difficult, because the degradation rate of PBDEs depended on the Br-rich phenyl ring with the lowest unoccupied molecular orbital (LUMO) localization. On the contrary, the complete debromination occurs easily in other systems with active hydrogen atoms as the main reactive species, such as chemically catalytic reduction systems. The review provides the knowledge on the chemical reductive technique of PBDEs, which would greatly help not only clarify the degradation mechanism but also design the more efficient system for the rapid and deep debromination of PBDEs in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

Membrane cleaning is a particular issue for spiral-wound membranes (SWM), as their cleanability is limited due to spacer-induced flow shadows behind spacer filaments. One option to enhance membrane cleaning efficiency is applying pulsed flow, characterised by a cyclic transition between high and low flow rates. This study examined how the cleaning success in hollow fibre membranes (HEM) and spiral-wound membranes (SWM) can be enhanced by pulsed flow at varying concentrations of the cleaning agent NaOH. The cleaning success was determined by protein removal and flux recovery analyses as well as scanning electron microscopy (SEM) imaging of cleaned membrane surfaces. The highest increase in cleaning efficiency as a result of pulsed flow was found for SWM at CNaOH = 0·03% (pH 11.3), where protein removal was increased by 48% over steady flow cleaning. SEM analyses confirmed that this was due to the pulsation-induced turbulence allowing improved access to spacer-induced flow shadows. Overall, cleaning success with pulsed flow at cNaOH = 0.03% could be improved in both HFM and SWM over that of steady flow at CNaOH = 0,30%, implying distinct reductions in chemicals consumption or shortened cleaning times when applying pulsed flow. [ABSTRACT FROM AUTHOR]

It is well-known that enzymes are molecules particularly susceptible to pH and temperature variations. Immobilization techniques may overcome this weakness besides improving the reusability of the biocatalysts. Given the strong push toward a circular economy, the use of natural lignocellulosic wastes as supports for enzyme immobilization has been increasingly attractive in recent years. This fact is mainly due to their high availability, low costs, and the possibility of reducing the environmental impact that can occur when they are improperly stored. In addition, they have physical and chemical characteristics suitable for enzyme immobilization (large surface area, high rigidity, porosity, reactive functional groups, etc.). This review aims to guide readers and provide them with the tools necessary to select the most suitable methodology for lipase immobilization on lignocellulosic wastes. The importance and the characteristics of an increasingly interesting enzyme, such as lipase, and the advantages and disadvantages of the different immobilization methods will be discussed. The various kinds of lignocellulosic wastes and the processing required to make them suitable as carriers will be also reported. • Use of lignocellulosic waste supports for lipase immobilization. • Analysis of protocols, supports, and application. • Costs reduction of chemical and industrial processes. • Recycling of potentially polluting waste materials. [ABSTRACT FROM AUTHOR]

In terms of improving photocatalytic hydrogen production performance, inexpensive and earth-rich cocatalysts have become promising alternatives to precious metals. Herein, a novel CoNi–TiO 2 photocatalyst composed of TiO 2 nanoflowers and CoNi alloy was prepared by hydrothermal and chemical reduction methods. Various characterizations and test results have confirmed that the further improvement of the photocatalytic performance of the CoNi–TiO 2 photocatalyst is mainly due to the fact that the bimetallic CoNi alloy can accelerate charge transfer and inhibit the recombination of photo-induced carriers. The hydrogen production rate of the prepared CoNi–TiO 2 is about 24 times higher than that of the pristine TiO 2 , and its hydrogen production rate value can reach 6580.9 μmol g−1 h−1, and showing comparable photocatalytic performance to 0.5 wt% Pt–TiO 2. In addition, combined with the characterization results, a probable mechanism for enhanced photocatalytic performance was proposed. This study provides favorable enlightenment for the design of a series of highly efficient non-precious metal TiO 2 -based photocatalysts. [Display omitted] • The TiO 2 nanoflowers were synthesized from MXene as raw material. • CoNi alloys were first used as the cocatalyst for TiO 2 nanoflowers to form a novel CoNi–TiO 2 photocatalyst. • The hydrogen production rate of CoNi–TiO 2 reached up to 6580.9 μmol·g−1·h−1, which is 24 times higher than that of TiO 2. [ABSTRACT FROM AUTHOR]

Topical treatment of cutaneous leishmaniasis holds great promise for decreasing drug associated side effects and improving efficacy. This study was aimed to develop mannosylated thiolated chitosan-coated silver nanoparticles (MTC Ag) loaded emulgel for the treatment of cutaneous leishmaniasis. MTC-Ag were synthesized via a chemical reduction method and were loaded into the emulgel. The nanoparticles had a zeta potential of +19.8 mV, an average particle size of 115 nm and a narrow polydispersity index of 0.26. In-vitro release profiles showed controlled release of silver ions from both the MTC-Ag and the emulgel-loaded MTC-Ag nanoparticles after 24 h. An ex-vivo retention study indicated 5 times higher retention of silver by the emulgel-loaded MTC-Ag than by the MTC-Ag nanoparticles. The in-vitro anti-leishmanial assay revealed that MTC-Ag had an excellent inhibitory effect on intracellular amastigotes, leading to ~90 % inhibition at the highest concentration tested. A 4-fold reduction in the IC 50 value was found for MTC-Ag compared to blank Ag nanoparticles. Cytotoxicity assay showed 83 % viability of macrophages for MTC-Ag and 30 % for Ag nanoparticles at a concentration of 80 μg/mL, demonstrating the improved biocompatibility of the polymeric nanoparticles. Drug release and retention studies corroborate the great potential of MTC-Ag-loaded emulgel for the treatment of cutaneous leishmaniasis. [Display omitted] • Mannosylated thiolated chitosan-coated Ag nanoparticles were loaded in an emulgel. • Improved release and retention of silver was observed compared to the controls. • A significant decrease in IC 50 and enhanced biocompatibility was attained. • The loaded nanoparticles show great potential for treating cutaneous leishmaniasis. [ABSTRACT FROM AUTHOR]

High-performance graphene fiber with intriguing functionality and mechanical strength is expected for wide potential applications. However, it still demands reliable means to realize the rapid wet-spinning of highly aligned fibers because of the insufficient gel strength of graphene oxide (GO) dope and the possible structural imperfections in the obtained fibers. Here, we demonstrate the fabrication of highly conductive and strong graphene fibers by regulating the rheology and spinnability of trace-carbonyl GO dispersion with silk fibroin (SF). The amphiphilic SF can form hydrogen bonds and π-π interactions with GO sheets to significantly enhance the gel strength of spinning dopes, enabling the conformation adjustment and sheet alignment under large drawing ratio and performance enhancement of the GO/SF fibers. After a chemical reduction, the highly orientated and stacked structure endows the fibers with an exceptional tensile strength of 938.6 MPa and a high electrical conductivity of 1501.7 S cm−1. Even more, the conductivity can be further increased to 2700.7 S cm−1, which is among the highest values for chemically reduced GO fibers. This work offers a promising method to produce strong, flexible, and robust graphene fibers for versatile applications in multifunctional fabrics, energy conversion, and health protection areas. We demonstrate the fabrication of conductive and strong graphene fibers reinforced with silk fibroin (SF). The strong interfacial interactions enhance the gel strength of spinning dope and help form compact and orientated structure, giving an exceptional strength of 938.6 MPa and an electrical conductivity of 1501.7 S cm−1. [Display omitted] [ABSTRACT FROM AUTHOR]

Efficiently constructing nanostructured Z-scheme heterojunctions with good interface contact is a desired route to optimize the photocatalytic property of the materials. In this work, novel 0D/1D/2D Z-scheme silver/silicon carbide/graphitic carbon nitride (Ag/SiC/CN) photocatalysts were prepared from Ag nanodots loaded on SiC nanofibers/CN nanosheets (SiC/CN) composite, using the calcination and chemical reduction routes. The Ag/SiC/CN composite with an optimal 3% Ag loading dose performs the best H 2 evolution rate of 2971 μmol g−1 h−1, which is approximately 8.8, 1.5 and 4.5 times compared to CN, SiC/CN and 3% Ag/CN, respectively. Besides the Ag/SiC/CN composite presents a high apparent quantum efficiency (7.3%) and outstanding photo-corrosion resistance stability. The Ag nanodots are served as efficient carriers transfer center and cocatalyst to construct Z-scheme heterojunction interface, which can help to generate more photo-generated carries, shorten the electron transmission distance and increase the electron transfer rate, certifying that 0D/1D/2D Z-scheme photocatalytic system is high-efficiency and has great advantages in photocatalytic applications. • A novel 0D/1D/2D Ag/SiC/g-C 3 N 4 nanoheterojunction photocatalyst was constructed. • Z-scheme system and multipurpose Ag nanodots conduce to enhance the property. • Ag/SiC/g-C 3 N 4 exhibits enhanced H 2 production activity and great cycling stability. • A detailed photocatalytic mechanism is illustrated for the activity improvement. [ABSTRACT FROM AUTHOR]

To overcome the shortcoming of rapid recombination of photoexcited electron-hole pairs of g-C 3 N 4 , noble metals are usually loaded as co-catalyst. However, conventional chemical reduction often brings about the loading of noble metal aggregates or nanoparticles that leads to a low atomic utilization efficiency. In this work, Pt atoms are highly dispersed on S-doped g-C 3 N 4 nanotubes through in situ pyrolysis of H 2 PtCl 6. Diffuse reflection infrared Fourier transform spectrum and XPS spectrum reveal that Pt exists in the state of +2 chemical valence and is anchored by coordination with diatomic N and S of g-C 3 N 4 , leading to a high dispersion and stabilization of Pt atoms in g-C 3 N 4 nanotube. The optimal H 2 production rate (0.3 wt% Pt) is 5304 μmol h−1g−1 and the turnover frequency (TOF) is 321.7 h−1 upon visible light illumination (λ > 420 nm), that is 3.2 times as high as Pt nanoparticle loaded g-C 3 N 4 nanotube with the same loading content. Our work provides a new way to anchor noble metal on photocatalyst via diatomic coordination and enhance the atomic utilization efficiency of noble metal co-catalyst. Moreover, the unique electronic structure of Pt2+ with electron-deficient 5d orbitals decreases the kinetic energy barrier and promotes H 2 evolution on the surface of photocatalyst. [Display omitted] • Dispersion of Pt on g-C 3 N 4 nanotube (CNNT) is realized via pyrolysis of H 2 PtCl 6 in Ar atmosphere. • High dispersion of Pt2+ on CNNT is confirmed by DRIFTS, XPS and TEM measurements. • N, S diatomic coordinated-anchor of Pt2+ on CNNT accelerates the transfer of photogenerated carriers. • Photocatalytic activity is tested for H 2 evolution from triethanolamine aqueous solution (λ > 420 nm). • The optimal TOF value is 3.2 times as high as Pt nanoparticle-loaded CNNT. [ABSTRACT FROM AUTHOR]

The hegemony of the agribusiness model in Latin America has consolidated the implementation of the Green Revolution technological package in which pesticides play a fundamental role. Yet in the face of its negative social, economic, and environmental effects, many medium-capitalized producers, petty commodity producers, and peasants have developed various food production strategies beyond extensive pesticide use. Drawing from the convergence between rural sociology and agroecology, we address the narratives and practices of farming families that are constructing alternatives to pesticides. Our analysis focuses not only on the productive dimension but also on the political and cultural aspects of the strategies that the subjects deploy when distancing themselves from the hegemonic practices of agribusiness. To approach this objective, we combine an analysis of in-depth interviews and ethnographic notes carried out in the municipality of Putaendo (Valparaiso, Chile) and the Antinaco-Los Colorados valley (La Rioja, Argentina). The article contributes to previous theoretical work on alternative agriculture by analyzing practices and narratives as seen from four different levels: microeconomics, macroeconomics, politics, and family labor. Drawing from a combination of these perspectives, the agrarian producers in our study explain and exemplify the growth, deployment, threats and staying power of practices distinct to or in opposition to agribusiness. Additionally, the research confirms that the analysis of alternatives for changing agriculture should consider the interaction between technical components, such as the reduction or elimination of chemical pesticides, economic balance, such as providing an "adequate" level of income, and cultural elements, such as the co-existence of economic systems. • Pesticide use generates economic and cultural dependency in agrarian subjects. • Input price increases or niche markets may motivate pesticide removal. • Peasant political strengthening is crucial to building alternatives to agribusiness. • Access to land and water has a major influence on sustainable strategies. • To remove pesticides, producers resort to hybridization of knowledge and technologies. [ABSTRACT FROM AUTHOR]

Generating oxygen vacancies is an effective way to improve photoelectrochemical (PEC) water splitting performance of semiconductor materials owing to the formation of shallow donor level and the supply of additional electron donor. Herein, oxygen vacancies were introduced into In 2 O 3 nanorods by a hydrothermal reduction method using NaBH 4 solution as the reductant, and the effects of hydrothermal reduction time on the oxygen vacancy concentration, optoelectronic property and PEC water splitting activity over In 2 O 3 nanorods were systematically investigated. The results of LSV, EIS and MS showed that the reduced samples displayed superior PEC performance and In 2 O 3-x -1 exhibited a highest photocurrent density of 0.97 mA cm−2 at 1.23 V vs. RHE under the irradiation of visible light, which was roughly 4 times of bare In 2 O 3. The remarkable performance of In 2 O 3-x -1 is mainly ascribed to the introduction of oxygen vacancies, which leads to better light absorption capacity, higher carrier concentration, and increased electron transport efficiency at the electrode/electrolyte interface. • Oxygen vacancies were introduced into In 2 O 3 nanorods by a wet chemical reduction. • The concentration of oxygen vacancies have significantly influence on the PEC performance. • In 2 O 3-x -1 showed the highest PEC performance due to a suitable oxygen vacancy content. [ABSTRACT FROM AUTHOR]

Surface and interface engineering of fluorine and tin doped indium oxide thin film at mild conditions to modulate optoelectronic properties is of great significance. Herein, a simple, low-cost solgel-spin-coating method was used to create a reproducible, scalable, stable, transparent, and conducting tin fluorine doped indium oxide thin film (FTIO thin film). To improve the electrical and optical properties of the thin film, a novel chemical reduction process was developed that did not require any reducing gas, inert atmosphere, and high temperature annealing. The chemical reduction time and concentration of NaBH 4 -dependent analysis shows a big drop (∼83%) in sheet resistance, due to increased oxygen vacancy in thin film. This increased oxygen vacancy was confirmed from XPS analysis. The treated FTIO thin film show lower resistivity (ρ = 0.95 × 10−3 Ω cm), highest figure of merit (0.001 Ω-1), roughness of 19.53 Å, and sheet resistance of 193 ± 3 Ω/sq, when compared to all other the solgel-spin-coating thin film process testified to date. To test the general applicability of the proposed reduction technique, it was applied to commercially available ITO thin film, and found to reduce sheet resistance by more than 53% (≤7 ± 1 Ω/sq) of the initial sheet resistance. Compared to other common post-treatment approaches, the proposed methodology reduces sheet resistance and could satisfy the demands of most real applications. [Display omitted] • Interface engineering induced charge carrier concentration and optical properties of the thin film. • Effect of various reducing agents on sheet resistance reduction is systematically investigated. • The chemical reduction shows significant reduction (∼83%) of sheet resistance. • We proposed a chemical reduction mechanism for the reduction of sheet resistance. [ABSTRACT FROM AUTHOR]

Dust control is of great significance to industrial process safety and environmental protection. Wet dust reduction is the most commonly used dust control technology, and the physical and chemical properties of water are closely related to its dust reduction ability. In order to improve dust reduction efficiency, scholars have done much fruitful work in the physical and chemical modification of water. It is essential to summarize the progress of this research direction and shows what is lacking at present in recent years. This paper reviews the research progress on improving the performance of water for dust reduction by physical and chemical methods in the past ten years. The physical methods are mainly adopted to improve dust reduction performance in spray technologies, which include air atomization, ultrasonic atomization, magnetized water and water mist charging. And the chemical methods are mainly used to prepare dust suppression materials, which can be distinguished by single-phase dust suppressants and gas-liquid two-phase dust suppression foam. In this paper, we analyze the advantages as well as disadvantages of various methods and point out the unresolved issues. Furthermore, the development directions are proposed to provide meaningful guidance for wet dust reduction technologies. [Display omitted] [ABSTRACT FROM AUTHOR]

The pollution resulting from the emergence of the contaminant perchlorate is anticipated to have a substantial effect on the water environment in the foreseeable future. Considerable research efforts have been devoted to investigating treatment technologies for addressing perchlorate contamination, garnering widespread international interest in recent decades. A systematic review was conducted utilizing the Web of Science, Scopus, and Science Direct databases to identify pertinent articles published from 2000 to 2024. A total of 551 articles were chosen for in-depth examination utilizing VOS viewer. Bibliometric analysis indicated that countries such as China, the United States, Chile, India, Japan, and Korea have been prominent contributors to the research on this topic. The order of ClO 4 − occurrence was as follows: surface water > groundwater > drinking water. Various remediation methods for perchlorate contamination, such as adsorption, ion-exchange, membrane filtration, chemical reduction, and biological reduction, have been suggested. Furthermore, the research critically evaluated the strengths and weaknesses of each approach and offered recommendations for addressing their limitations. Advanced technologies have shown the potential to achieve notably enhanced removal of perchlorate and co-contaminants from water sources. However, the low concentration of perchlorate in natural water sources and the high energy consumption related to these technologies need to be solved in order to effectively remove perchlorate from water. [Display omitted] • The research hotspots and progress of perchlorate in water were demonstrated. • 551 articles were selected to analyze ClO 4 − occurrence and removal technologies. • Perchlorate research hot spots are China, the United States, and Chile. • Approaches available for ClO 4 − removal over last 20 years was elaborated. • Hybrid treatments were promising green technology of perchlorate removal from water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel 2-step method for efficient & selective nitrate to nitrogen conversion. • Ag NWs electrode enable > 99 % selective electrocatalytic nitrate-to-nitrite reduction. • Ag NWs electrodes can be easily used in static and flow electrolytic cells. • Chemical reduction of nitrite to N 2 using sulfamic acid: ∼100 % selectivity. • Electrocatalysis + chemical reduction: up to 99.44 % nitrate-to-nitrogen selectivity. Nitrate pollution in natural water bodies poses a severe threat to human health and the environment. Developing efficient and environmentally friendly nitrate removal methods has become a global need. Electrochemical techniques offer a cost-effective strategy for nitrate remediation; however, the complexity of the reaction and the formation of multiple by-products make the selective production of harmless nitrogen a challenging task. This study proposes a novel two-step strategy to achieve high efficiency and selectivity in converting nitrate into nitrogen. First, a membrane electrode consisting of silver nanowires (Ag NWs) is used to electrochemically reduce nitrate to nitrite through a direct electron transfer pathway. Whether in a static electrolytic cell or a flow cell, the process has very high nitrite selectivity and Faraday efficiencies, with Faraday efficiency up to 98.40 % and selectivity up to 99.90 % at −1.0 V vs Ag/AgCl. Subsequently, the nitrite is converted into nitrogen through a specific reaction with sulfamic acid with near 100 % conversion and selectivity. By coupling these two reactions, the selectivity for converting nitrate to nitrogen can reach more than 99 %. In addition, the membrane electrode can be readily used in a flow-through electrolytic cell to treat nitrates at a maximum rate of 150 L h−1 m−2. When operated at 50 L h−1 m−2, the membrane electrode demonstrates relatively stable performance for 100 h, reducing nitrates at 1.61 mM to below 0.81 mM (50 ppm), as recommended by the World Health Organization for drinking water. This novel synergistic approach not only enhances nitrogen selectivity but also simplifies the process of electrocatalytic nitrate reduction, making it a promising method for nitrate removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel and sustainable dye sewage treatment strategy is proposed. • This is hydrogen evolution coupled with dye hydrogenation reactions. • A series of matched bifunctional catalysts are thus developed. • Its cost and efficiency are superior to those of chemical reduction method. • This strategy exhibits high universality towards various dye sewages. A water electrolysis coupled with chemical reduction strategy is proposed to realize sustainable wastewater treatment. Correspondingly, a series of transition-metal (e.g., iron, cobalt, nickel and copper) nanoparticles anchored on zinc oxide nanowire array (ZnO NA) with bifunctional catalytic activity for hydrogen evolution reaction together with dye hydrogenation reaction (HER/DHR) are developed, while their catalytic activity are comparatively investigated at the same time. This renewable strategy with environmental and economic benefits exhibits high-efficiency treatment capability towards various dye wastewaters. For example, a typical system based on nickel nanoparticles with ZnO NA supports, which exhibits higher catalytic activity towards the HER/DHR than those of other three counterparts under the same conditions, can transform waste 4-nitrophenol into valuable 4-aminophenol with an apparent rate constant of 36.95 × 10-3 min−1 and a conversion rate of 98.32 %, thereby achieving dye decolorization and resource regeneration simultaneously. Its efficiency is significantly superior to that of chemical method dependent on traditional reducing agents and commercial nickel materials, demonstrating its stronger competitiveness. It is mainly benefited from the interface synergistic effect of nickel nanoparticles and zinc oxide nanowires. This novel system is expected to replace conventional sewage remediation technologies for efficient, inexpensive, and eco-friendly dye degradation, and thus is very important for energy and environmental sustainability. [ABSTRACT FROM AUTHOR]

• A six-nuclear compound {[Bi 6 (tza) 5 (NO 3) 2 (HO) 5 O 3 ]·H 2 O} n has been synthesized. • The compound itself is a stable and efficient photocatalyst for the degradation of methyl orange (MO) under pH conditions of 6.0–8.0. • The {[Bi 6 (tza) 5 (NO 3) 2 (HO) 5 O 3 ]·H 2 O} n can also be used as a precursor and it can be hydrolyzed in situ to BiOCl under acidic conditions (pH = 1.0–5.0) and to Bi 2 O 2 CO 3 under alkaline conditions (pH = 9.0–11.0), which also have efficient photocatalytic performance. A polynuclear metal-organic framework, {[Bi 6 (tza) 5 (NO 3) 2 (OH) 5 O 3 ]·H 2 O} n (Htza=1H-tetrazole-1-acetic acid), was successfully synthesized and characterized, and its photocatalytic properties, along with those of its derivatives, were investigated. The crystal structure of the compound was determined to belong to the orthorhombic space group Pn ma , featuring a 3D framework comprising cage-like [Bi 6 (µ 3 -O) 3 (µ 3 -OH) 5 ]7+ clusters. {[Bi 6 (tza) 5 (NO 3) 2 (OH) 5 O 3 ]·H 2 O} n demonstrated significant photocatalytic activity with UV light response within the pH range of 6.0–8.0 and a band gap energy of 3.32 eV. Under optimal conditions, a reduction in chemical oxygen demand (COD) and total organic carbon (TOC) (from 126.90 mg/L to 4.57 mg/L) clearly validated the efficient methyl orange degradation. The main active groups in the degradation process were h+, ·O 2 − and ·OH, and the catalyst demonstrated reusability for up to six cycles. Moreover, it was hydrolyzed to Bi 2 O 2 CO 3 and BiOCl under alkaline (pH=9.0–11.0) and acidic (pH=1.0–5.0) conditions, respectively, thus serving as a valuable precursor. Notably, the Bi 2 O 2 CO 3 and BiOCl derivatives exhibited higher catalytic activities than catalysts synthesized using alternative methods under the same experimental conditions. Therefore, within the pH range of 1.0–11.0, {[Bi 6 (tza) 5 (NO 3) 2 (OH) 5 O 3 ]·H 2 O} n , along with its in situ derivatives BiOCl and Bi 2 O 2 CO 3 , were highly efficient UV light-driven photocatalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Exploring a facile, rapid and efficient route to produce metal-organic frameworks (MOFs) with highly accessible active sites is of great importance for catalysis. Here we demonstrate the CO 2 coordination can drive low temperature rapid synthesis of porphyrin-based bismuth-MOFs (Bi-PMOFs) by utilizing synergistic physical and chemical properties of supercritical CO 2 (SC-Bi-PMOFs). The molecular-level role of scCO 2 in the synthesis of SC-Bi-PMOFs have been investigated through a series of characterizations including in-situ time-dependent infrared spectroscopy, wherein chemical coordination of CO 2 promotes to fabricate 2D SC-Bi-PMOFs nanosheets. Moreover, the formation of Cu-PMOFs and Fe-PMOFs proves the universal scCO 2 strategy for synthesizing PMOFs. Density functional theory (DFT) calculations together with experiments results confirm the SC-Bi-PMOFs with abundant active sites guarantee efficient ligand-to-metal charge transfer and reduction efficiency of CO 2. The high-efficiency utilization of CO 2 for synthesizing a series of MOFs and subsequent catalysis on photocatalytic CO 2 reduction for valuable chemicals realize the carbon recycle. [Display omitted] • CO 2 -assisted rapid synthesis of Bi-PMOFs with well-exposed active site at low temperature. • CO 2 chemical coordination facilitates the synthesis of 2D Bi-PMOF nanosheets. • SC-Bi-PMOFs exhibit superior photocatalytic CO 2 reduction activity, an efficient strategy for realizing carbon cycle. • A series of M-PMOFs (M= Cu and Fe) were synthesized, verifying the universal prospect of scCO 2 in the synthesis of PMOFs. [ABSTRACT FROM AUTHOR]

Owing to the presence of valence shells for charge transfer, a high theoretical specific capacitance, and variable redox properties, MnO 2 appears as a promising agent in the realm of energy storage. Crystallographic structures of manganese oxide (MnO 2), a transition metal oxide, play a crucial role in determining its capacitive behavior by controlling the ion intercalation and double-layer formation. In this work, two different phases of MnO 2 were synthesized using the facile chemical reduction method and biological method, say α-MnO 2 and λ-MnO 2. The phases were incorporated with different carbonaceous additives including GO and CNT while maintaining a constant weight ratio of 8:1:1 between active materials (MnO 2), additive, and PVDF binder. Among different composites formed, the best electrode performance is demonstrated by λ-MnO 2 /CNT/PVDF composite with an excellent specific capacitance of 356 F/g at a scan rate of 1 A/g. Moreover, the best-performing electrodes are investigated with a symmetrical two-electrode system yielding a wide potential window of 1.8V with an outstanding power density of 13.5 KW/Kg at 5 A/g and an energy density of 53.78 Wh/Kg at 1A/g having a specific capacitance of 190 F/g. [ABSTRACT FROM AUTHOR]

Lumping of isomers is an effective approach to reduce large chemical kinetic mechanisms containing a substantial number of chemical species. However, a simple lumping of all isomers with identical chemical compositions leads normally to large prediction uncertainties of the lumped model, by neglecting the chemical functionalities of isomers in terms of, for instance, their oxygenated groups and radical sites, which affect their formation and consumption pathways significantly. Thus, the definition group of lumped species is crucial, which is, however, typically done manually in the model reduction by trial and error. In the combustion community, large kinetic mechanisms are mostly developed based on deriving chemical reactions and their involved species according to the so-called reaction class, which produces a large number of molecules with identical compositions but different structures and chemical functionalities. Thus, in this study, an automatic chemical lumping approach is proposed to efficiently reduce the kinetic mechanisms of large hydrocarbon fuels by defining the group of lumped isomers according to their reaction classes and chemical functionalities automatically. For the species produced by the low-temperature reaction classes, such as hydroperoxyalkyl radicals, peroxy hydroperoxide radicals, and cyclic ethers, their isomers are lumped together, if their formation reactions have similar chemical characteristics with respect to the ring sizes of transition states. Reaction rate constants of lumped reactions are evaluated based on numerical results of the detailed mechanism. By using the derived method, a mechanism of n -decane with 1692 species is reduced to 137 species and a skeletal mechanism of n -heptane, iso-octane, toluene, and ethanol mixture with 489 species is reduced to 298 species successfully, in conjunction with the directed relation graph with error propagation (DRGEP) method. Agreement is observed between lumped and original mechanisms, which demonstrates the validity and effectiveness of the present approach. • An automatic chemical lumping method of functional isomers is proposed. • Lumped isomers are grouped according to the reaction classes and chemical properties. • Low-temperature species are lumped according to ring sizes of their transition state. • A model of n -decane with 137 species is obtained from a model with 1692 species. • A reduced model of n -heptane, iso-octane, toluene, and ethanol mixture is obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel reduction coupled with oxidation process for TN removal was proposed. • The FeR-PSO process could remove TN including both NO 3 −-N and NH 4 +-N. • N 2 was the main product of inorganic nitrogen conversion. • Over 90% TN could be removed from actual pickle factory wastewater. The conversion of nitrate nitrogen (NO 3 −-N) or ammonia nitrogen (NH 4 +-N) to dinitrogen (N 2) by chemical process for total nitrogen (TN) removal is meaningful, but still a challenge in wastewater treatment. Herein, zero valent iron (Fe0) loaded active carbon (Fe0@AC) was prepared and used to remove TN from the nitrogen-containing wastewater by an efficient chemical reduction coupled with oxidation process (FeR-PSO). In the step of NO 3 −-N reduction by Fe0@AC, Fe0@AC with 25 wt% Fe0 could reduce 100 % NO 3 −-N with the initial concentration of 50 mg N/L after 60 min at the Fe0@AC dosage of 9 g/L and initial pH of 3.0, and over 30 % NO 3 −-N could be reduced to N 2. In the subsequent oxidation step, persulfate (PS) and magnesium oxide (MgO) were introduced into the solution after NO 3 −-N reduction to selectively oxidize NH 4 +-N to N 2. The removal efficiency of NH 4 +-N and N 2 selectivity after 30 min were 100 % and over 90 %, respectively, at the MgO dosage of 8 g/L and the PS dosage of 20.25 g/L. The developed FeR-PSO process could remove 93.40 % of TN from simulated wastewater, and over 90 % of TN from two actual pickle factory wastewaters. The possible mechanisms of NO 3 −-N reduction and NH 4 +-N oxidation by FeR-PSO process were proposed. These findings provide new insights for TN removal from NO 3 −-N containing wastewater or wastewater containing both NO 3 −-N and NH 4 +-N by chemical process. [ABSTRACT FROM AUTHOR]

[Display omitted] • aAOB-mediated Fenton improved ADS dewatering while reducing acid/Fe2+/H 2 O 2 usage. • aAOB acidified ADS by oxidizing NH 4 + inherently present in ADS into NO 2 –/FNA/NO 3 –. • The diverse reactions among FNA, H 2 O 2 and Fe2+ yielded more ROS and RNS in sludge. • ESI FT-ICR MS was used to reveal molecular characteristics of DOM in sludge TB-EPS. • DOM was dominated by smaller and more hydrophobic molecules with low unsaturation. Due to the high alkalinity, fine particle size, and the relative abundance of refractory and adhesive biopolymers in anaerobically digested sludge (ADS), the application of traditional Fenton oxidation to improve ADS dewatering faces significant technical and economic challenges, e.g., high doses of chemicals (acid/Fe(II)/H 2 O 2) consumption. Herein, we proposed an acidophilic ammonia-oxidizing bacteria (aAOB) mediated Fenton to address these challenges. Compared with the traditional Fenton, the modified Fenton with aAOB improved the rate and extent of ADS dewatering, leading to a three-fold decrease in Fe(II)/H 2 O 2 consumption while avoiding the need to add acid for pH adjustment. Treated sludge specific resistance to filtration and normalized capillary suction time decreased by 98.9 % and 89.9 %, respectively, and the filtration-compression time was reduced by ∼ 86.5 %. Mechanistically, oxidation of NH 4 + inherently present in the sludge by aAOB into NO 2 –/free nitrous acid (FNA)/NO 3 – reduced the pH from 7.8 to ∼4.0 within 2 days. This not only created the desired pH for sludge Fenton oxidation, but also facilitated the generation of more diverse and abundant active radicals (OH, O 2 –, NO, and NO 2) in the sludge because of the additional reaction of H 2 O 2 with biogenic FNA in addition peroxide's reaction with Fe(II). Radical oxidation decomposed CHONS, CHONSP, and CHOP-containing biopolymers in TB-EPS and especially proteins and lipids into relatively hydrophobic small molecules with low unsaturation, and disintegrated bioflocs into disperse structure with lowered surface roughness, increased cell lysis, and looser proteins secondary structure. These changes, together with coagulation by Fe(III), helped release mechanically bound water from the ADS. These results suggested that the synergistic effects between microbial ammonia oxidation and Fenton oxidation have the potential to facilitate cost-effective dewatering of ADS. [ABSTRACT FROM AUTHOR]

Hydrogen generation via methanol steam reforming is a promising method for producing renewable energy. In this work, a series of Mn2+-substituted CuAl 2 O 4 spinels were prepared by solution combustion method, and the crystal structure, micromorphology, chemical constitution, reduction behavior, acidity, specific surface area and surface chemical state of the spinels were comprehensively characterized by various equipments. The obtained spinels were washcoated on Cu foams to prepare monolithic catalysts, and the catalytic performance of the catalysts was evaluated in a methanol steam reforming microreactor. Compared with the binary Cu–Al spinel, the Mn2+ substitution led to a decrease in the particle size, a change in the chemical composition and reduction behavior, a decline in the acidity, an increase in the specific surface area, and an improvement in the surface chemical state. As a result, the release rate of active Cu from the Mn-containing CuAl 2 O 4 spinel was significantly slowed down and the formed nanoparticles were fine, which was believed to be in favor of maintaining a stable catalytic performance longer. Among the prepared catalysts, the monolithic catalyst loaded with Cu 0.4 Mn 0.6 Al 2 O 4 exhibited the highest activity and stability. The findings of this work suggested that introducing Mn2+ might be a promising way to regulate the Cu releasing property for obtaining a better sustained release catalyst system. [Display omitted] [ABSTRACT FROM AUTHOR]

Efficient treatment of toxic organic pollutants in water/wastewater by using innovative, cost efficient, and simple technologies has recently become an important issue worldwide. Remediation of these pollutants with chemical reduction in the presence of a nano-sized catalyst and a reducing agent is one of the most useful methodologies. In the present study, we have designed a promising heterogeneous catalyst system (Pd@CS-NiO) by easy and efficient stabilization of palladium nanoparticles on the surface of microspheres composed of chitosan (CS)-NiO particles (CS-NiO) for the reduction of organic pollutants. The nano-structure of the developed Pd@CS-NiO was successfully validated using FE-SEM, XRD, EDS, TEM, and FTIR/ATR and its particles size was determined as 10 nm. The catalytic power of Pd@CS-NiO was then assessed in the reduction of 4-nitro- o -phenylenediamine (4-NPDA), 4-nitrophenol (4-NP), 4-nitroaniline (4-NA), 2-nitroaniline (2-NA), and some organic dyes, namely methylene blue (MB), methyl orange (MO), and rhodamine B (RhB) in aqueous medium at room temperature. The reductions were thoroughly studied spectro-photometrically. The tests displayed that the synthesized Pd@CS-NiO was a highly active and useful catalyst that reduced these pollutants in 0–145 s. Moreover, the rate constants for 2-NA, 4-NP, 4-NA, 4-NPDA, MO, and RhB were found to be 0.017 s−1, 0.011 s−1, 0.006 s−1, 0.013 s−1, 0.023 s−1, and 0.03 s−1, respectively. Moreover, the recycling test indicated that Pd@CS-NiO may be recovered easily thanks to its micro size nature and could be used up to seven steps, confirming its practical application potential. • Novel palladium nanocatalyst was prepared on NiO-modified chitosan beads. • Characterization of nano-structure of Pd@CS-NiO was performed by FT-IR, FE-SEM, TEM, EDS, and XRD analyses. • Pd@CS-NiO displayed good performance against reduction of environmental contaminants. • Pd@CS-NiO was recovered/reapplied up to seven times. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developed a novel continuous-flow cascade photocatalytic system for elimination of SMX. • Tailored photoreactor design maximizes the photonic efficiency for SMX degradation. • System optimization achieved a high photocatalytic activity toward SMX removal. • The three-step cascade system achieved 80% SMX removal efficiency from hospital sewage. • The system achieved an electrical energy per order (E EO) value of 2.03 kWh/m3. In this study, we introduce a novel continuous-flow cascade photocatalytic system specifically designed to efficiently remove sulfamethoxazole (SMX) from hospital wastewater, addressing the critical need for sustainable pharmaceutical wastewater treatment. The system utilizes a carbon sponge-based TiO 2 photocatalyst synthesized via a hydrothermal process under mild conditions. The system's design incorporates multiple stages in a cascade configuration, meticulously optimized to enhance photocatalytic efficacy, thereby significantly improving the rate of SMX elimination while minimizing energy consumption. The study encompasses comprehensive characterization of the photocatalyst, including matching its absorption spectrum to the emission spectrum of the light source, as well as fine-tuning key operational parameters such as catalyst quantity, flow rates, and cascade configuration. Real-world application tests confirm the system's efficiency, achieving approximately 80 % SMX removal efficiency alongside a notable reduction in Chemical Oxygen Demand (COD) levels. Furthermore, the system's energy efficiency, as reflected by an Electrical Energy per Order (E EO) value of 7.53 kWh/m3, highlights its potential for scalable and sustainable wastewater treatment solutions. This study not only contributes significantly to the field of environmental catalysis but also represents a significant advancement in sustainable environmental management, offering a promising solution to the urgent challenge of pharmaceutical pollution in water sources. [ABSTRACT FROM AUTHOR]

[Display omitted] • Trithiocyanuric-linked covalent triazine frameworks are fabricated via facile condensation reaction. • The fabricated TTC-CTFs enabled photo-enhanced precious metal recovery. • TTC-CTFs were competent for continuous flow-through gold recovery from e-waste leachate. • Recovery mechanism was systematically investigated. Precious metals recovery from secondary resources is crucial for ensuring the sustainable supply of resources and development of circular economy. Herein, the trithiocyanuric-linked covalent triazine frameworks (denoted as TTC-CTFs) are proposed and constructed for efficient recovery of precious metals. As expected, the proposed TTC-CTFs afford ultrahigh uptake capacities of 3365 mg g−1 for Au(III) and 1125 mg g−1 for Pt(IV) under light irradiation, achieving the respective 2.3-fold and 1.5-fold enhancement relative to those in the dark and outperforming the previously reported materials. Meanwhile, fast kinetics and superior recyclability are achieved, as reflecting by 15 min of the equilibrium time and neglect decline in recovery efficiency during ten cycles. Post-recovery characterizations and theoretical calculations reveal the combination of adsorption, photoreduction/chemical reduction, and crystallization is responsible for the photo-enhanced Au recovery. Significantly, TTC-CTFs are also competent for selective and efficient gold recovery from the computer processing unit (CPU) leachate, as companied by 99% of recovery efficiency and considerable profit, highlighting the feasibility of the proposed TTC-CTFs for the precious metal recovery from the actual e-waste. [ABSTRACT FROM AUTHOR]