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Constructing efficient electrocatalysts for the oxygen reduction reaction (ORR) is crucial for the commercialization of metal-air batteries. Iron oxide-based catalysts exhibit promising potential for ORR. However, addressing the issue of inferior catalytic performance is essential, and a comprehensive understanding of the catalytic mechanism of iron oxide-based catalysts is also lacking. In this study, we present Fe 3 O 4 nanoparticles encapsulated in N-doped graphitic carbon layers (NGC) hosted by hierarchically porous carbon (Fe 3 O 4 @NGC), achieved through a facile dual melt-salt template strategy. The encapsulation of Fe 3 O 4 nanoparticles protects them from corrosion and exfoliation, endowing the catalysts with superior stability. Density functional theory (DFT) calculations discover that the electronic interaction between Fe 3 O 4 nanoparticles and N-doped graphitic carbon layers induces directional interfacial electron transfer, which effectively modulates the surface electronic structure to improve the binding ability to O 2 , weaken the OO bond, and optimize the adsorption of intermediates, thus boosting the intrinsic activity. DFT unveils that the C atoms nearest to graphitic-N in NGC are active sites. Finally, the synergistic effects of Fe 3 O 4 nanoparticles and NGC result in outstanding ORR performance and superior stability and methanol tolerance of Fe 3 O 4 @NGC, with a half-wave potential of 0.89 V, surpassing that of Pt/C by 50 mV. Fe 3 O 4 @NGC also shows better performance than Pt/C when used as the air-electrode catalyst in zinc-air battery., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Photocatalytic reduction of CO 2 in pure H 2 O media to produce chemicals presents an appealing avenue for simultaneously alleviating energy and environmental crises. However, the rapid recombination of photogenerated charge carriers presents a significant challenge in this promising field. Heterojunction engineering has emerged as an effective approach to address this dilemma. Here, by decorating 2D NiAl-layered double hydroxides (NAL) onto bismuth oxybromide (BOB), we have created a S-scheme heterojunction (N 1 B 1 composite). This catalyst affords CO 2 -to-CO yields of 102.30 μmol g -1 with a selectivity of 100 %. Ultraviolet photoelectron spectroscopy (UPS) and in-situ irradiated X-ray photoelectron spectroscopy (ISI-XPS) reveal that charge transfer occurs efficiently from BOB to 2D-NAL upon light irradiation. The designed N 1 B 1 heterojunction achieves 7.3-fold and 2.1-fold increase in the internal electric field strength compared to bare 2D-NAL and BOB, respectively, which should be accountable for the improved charge migration. Additionally, pulsed chemisorption and in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) show the presence of multiple carbonate intermediates with activated OCO bonds upon N 1 B 1 composite, with *CO 2 - being identified as the most crucial species for CO production., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The efficiency of photocatalytic Nitric Oxide(NO) oxidation is limited by the lack of oxygen(O 2 ) active sites and poor charge carrier separation. To address this challenge, we developed a molecular Cobalt Phthalocyanine modified MIL-68(In)-NH 2 photocatalyst with a robust Built-in electric field(BIEF). In the 2 % CoPc-MIN sample, the BIEF strength is increased by 3.54 times and 5.83 times compared to pristine CoPc and MIL-68(In)-NH 2 , respectively. This BIEF facilitates the efficient S-scheme charge transfer, thereby enhancing photogenerated carrier separation. Additionally, the Co-N4(II) sites in CoPc can effectively trap the separated photoexcited electrons in the S-scheme system. In addition, the Co-N4(II) sites can also serve as active sites for O 2 adsorption and activation, promoting the generation of superoxide radical (O 2 - ), thereby driving the direct conversion of NO to nitrate(NO 3 - ). Consequently, the 2 % CoPc-MIN sample exhibits a remarkable photocatalytic NO removal efficiency of 79.37 % while effectively suppressing the formation of harmful by-product nitrogen dioxide(NO 2 ) to below 3.5 ppb. This study provides a feasible strategy for designing high-efficiency O 2 activation photocatalysts for NO oxidation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The lack of compactness in heterojunction interfaces and poor charge separation is a great challenge in developing high-efficiency heterojunction photocatalysts. Herein, a novel Bi 4 Ti 3 O 12 -BiPO 4 heterojunction was successfully prepared for the first time by epitaxial growth of BiPO 4 on the surface of Bi 4 Ti 3 O 12 nanosheets. The optimized Bi 4 Ti 3 O 12 -BiPO 4 -0.5 increased the NO oxidation efficiency to 73.05%, surpassing pure Bi 4 Ti 3 O 12 (63.45%) and BiPO 4 (8.35%). Experiments and theoretical calculations indicated that the closely contacted heterointerface between BTO and BPO promoted the generation of the built-in electric field, which led to the formation of the Z- scheme transfer pathway for the photogenerated carriers. Therefore, the separation of photogenerated carriers was facilitated while retaining high redox potential, generating more ·O 2 - and ·OH to participate in NO oxidation. Furthermore, the adsorption of NO and O 2 was enhanced by introducing BiPO 4 , further improving the photocatalytic NO oxidation performance. This work emphasizes the critical role of heterointerface in accelerating charge transfer, providing a basis for the design and construction of tightly contacted heterojunction photocatalysts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Ligand functionalization is an effective way to endow Metal-organic frameworks (MOF) with versatility for multiple applications by introducing or displaying substituents without changing the origin framework. In this work, the original MIL-101(Fe) was modified by functional groups, including -NH 2 , -NO 2 , -CH 3 , and -Cl substituents. The Bader charge results and electron localization function (ELF) quantitatively indicated that the functional ligands with different properties can regulate the electron structure of transition-metal centers through interface-charge redistribution. Accompanying the higher adsorption and utilization rate of peroxymonosulfate (PMS), more than 96% of acetaminophen (APAP) was degraded with a mineralization rate of 40.17% under the NH 2 -BDC/PMS system. In terms of mechanism, the amino group not only accelerated the regeneration of Fe(II) via the NCFe electron-transfer path, but also stimulated the appearance of high-valent Fe species. Meanwhile, the degradation pathways of APAP were proposed by integrating the results of liquid chromatograph-mass spectrometry (LC-MS) and Frontier molecular-orbital theory. Finally, the NH 2 -BDC/PMS system reveals long-term stability, nonselectivity, low biotoxicity as well as secondary pollution for pollutant degradation, which is a considered candidate for further environmental applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Many lanthanide complexes do not form gel or even exhibit characteristic luminescence of lanthanide ions, which limits their applications in many fields. Therefore, there is an urgent need for a third component that can not only promote emission but also gel the lanthanide complex system to construct new smart materials such as time-dependent information encryption and anti-counterfeiting materials. Herein, a luminescent lanthanide metallogel was successfully prepared by using the third component sodium carboxymethyl cellulose (NaCMC) to induce the gelation and luminescence of the complex (H 3 L/Tb 3+ ) of 4,4',4″-((benzene-1,3,5-tricarbonyl)tris(azanediyl)) tris(2-hydroxybenzoic acid) (H 3 L) and Tb 3+ . The H 3 L/Tb 3+ complex itself does not form gel and has no characteristic luminescence of Tb 3+ . Moreover, the multicolor emission of H 3 L/Tb 3+ /NaCMC gels was prepared based on Förster resonance energy transfer (FRET) platforms to obtain a high-security level information encryption and anti-counterfeiting materials. These multicolor emission gels exhibit emission color tunability with time dependence due to the different energy transfer efficiencies at each pH node controlled by glucono-δ-lactone hydrolysis time. Based on the time response characteristics, the time-dependent information encryption and anti-counterfeiting materials are developed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

CO 2 photocatalytic reduction is an excellent strategy for promoting solar-to-chemical energy conversion and alleviating the severe environmental crisis. In this study, 2D indium oxide (IO) is decorated on 2D bismuth oxybromide (BOB) nanosheets to gain BOB/IO (B x I y ) heterojunction. The optimal B 3 I 1 composite affords a CO production rate of 54.2 μmol⋅g -1 , about 2.2 times and 11.3 times higher than those of the pristine BOB and IO, respectively. The introduction of IO significantly enhances the internal electric field (IEF), leading to accelerated charge transfer and prolonged lifetime of the photogenerated carriers. In the B x I y composite, the BOB and IO serve as the electron acceptor and donor, respectively, facilitating the reduction of CO 2 and oxidation of H 2 O. In-situ DRIFTs spectra are used to confirm the catalytic active sites and provide insights into the mechanism of CO 2 photoreduction. The results suggest *COOH and *CO 2 - species played a crucial role in the formation of CO. This work presents a valuable perspective on understanding the charge transfer route and developing highly efficient photocatalysts for CO 2 photoreduction., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

From the swollen LDH, bulky [Mo 3 S 13 ] 2- anions are facilely introduced into the LDH interlayers to assemble the Mo 3 S 13 -LDH composite, which exhibits excellent iodine capture performance and good irradiation resistance. The positive-charged LDH layers may disperse the [Mo 3 S 13 ] 2- uniformly within the interlayers, providing abundant adsorption sites for effectively trapping iodine. The Mo-S bond serving as a soft Lewis base has strong affinity to I 2 with soft Lewis acidic characteristic, which is conducive to improvement of iodine capture via physical sorption. Besides, chemisorption has a significant contribution to the iodine adsorption. The S 2 2- /S 2- in [Mo 3 S 13 ] 2- can reduce the I 2 to [I 3 ] - ions, which are facilely fixed within the LDH gallery in virtue of electrostatic attraction. Meanwhile, the S 2 2- /S 2- themselves are oxidized to S 8 and SO 4 2- , while Mo 4+ is oxidized (by O 2 in air) to Mo 6+ , which combines with SO 4 2- forming amorphous Mo(SO 4 ) 3 . With the collective interactions of chemical and physical adsorption, the Mo 3 S 13 -LDH demonstrates an extremely large iodine adsorption capacity of 1580 mg/g. Under γ radiation, the structure of Mo 3 S 13 -LDH well maintains and iodine adsorption capability does not deteriorate, indicating the good irradiation resistance. This work provides an important reference to tailor cost-effective sorbents for trapping iodine from radioactive nuclear wastes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Rational design and construction of bifunctional heterostructure electrocatalysts with high-conductivity and more active sites is imperative for water splitting. Herein, based on the tunable property of layered double hydroxide laminates cations, topological transformation technology and template confine method, a series of high-performance bifunctional catalysts composed of transition metal doping NiCo 2 S 4 (MNiCoS 4 , M = Cu, Fe, Zn, Mn) and 1T-MoS 2 were in-situ fabricated on nickel foam. In particular, CuNiCoS 4 /1T-MoS 2 exhibits an ultralow overpotential of 163 mV at 50 mA cm -2 for oxygen evolution reaction (OER) and favorable hydrogen evolution reaction activity. The two-electrode system requires only 1.52 V to attain a current density of 10 mA cm -2 . To the best of our knowledge, its OER electrocatalytic activity far exceed state-of-art catalysts reported. The outstanding performance of this series of catalysts can be attributed to two aspects. First, the highly conductive 1T-MoS 2 can facilitate electron transfer, and second, the defect-rich heterostructure can effectively regulate the electronic structure of the active metal and expose abundant active sites. This work provides a valuable strategy for developing high activity electrocatalysts for efficient water splitting., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Carbon nitride is an attractive non-metallic photocatalyst due to its small surface area, rapid electron-hole recombination, and low absorption of visible light. In this study, one-dimensional carbon nitride nanotubes were successfully synthesized by supramolecular self-assembly method for photocatalytic reduction of CO 2 under mild conditions. The material demonstrates significantly improved CO 2 -to-CO activity compared to bulk carbon nitride under visible light irradiation, with a rate of 12.58 μmol g -1 h -1 , which is 3.37 times higher than that of pristine carbon nitride. This enhanced activity can be attributed to the abundant oxygen defects and nitrogen vacancies in the unique tubular carbon nitride structure, which results in the generation of more active sites and the efficient acceleration of the migration of photogenerated electron-hole pairs. Various characterizations collectively support the presence of these defects and vacancies. Moreover, in situ DRIFTS spectroscopy supported the proposed reaction mechanism for the photoreduction of CO 2 . This eco-friendly design approach provides novel insights into utilizing solar energy for the production of value-added products., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Tandem catalysts consisting of metal oxides and zeolites have been widely studied for catalytic carbon dioxide (CO 2 ) hydrogenation to lower olefins, while the synergies of two components and their influence on the catalytic performance are still unclear. In this study, the composite catalysts composed of indium oxide loaded with zirconia (In 2 O 3 /ZrO 2 ) and silicoaluminophosphate molecular sieve number 34 (SAPO-34) are developed. Performance results indicate that the synergies between these two components can promote CO 2 hydrogenation. Further characterizations reveal that the chabazite (CHA) structure and acid sites in the SAPO-34 are destroyed when preparing In-Zr/SAPO by powder milling (In-Zr/SAPO-M) because of the excessive proximity of two components, which inhibits the activation of CO 2 and hydrogen (H 2 ), thus resulting in much higher methane selectivity than the catalysts prepared by granule stacking (In-Zr/SAPO-G). Proper granule integration manner promotes tandem reaction, thus enhancing CO 2 hydrogenation to lower olefins, which can provide a practicable strategy to improve catalytic performance and the selectivity of the target products., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Template is frequently studied as a structure-directing agent to tune the nanomorphology of photocatalysts. However, the influences of template on the polymerization of precursors and compositions of the resulting samples are rarely considered. Herein, a biomass carbon-modified graphitic carbon nitride (CCNx) with a thin-layer morphology is synthesized via one-pot surface-assisted polymerization of melamine precursor on organic yeast. The formation of the hydrogen bond between melamine and yeast induces a strong interfacial confinement, giving rise to small-sized CCNx. In addition, the carbon materials derived from yeast dramatically broaden n → π* visible light harvesting, improve electron delocalization, and greatly enhance charge carrier separation. The optimized CCNx presents a much higher photocatalytic hydrogen production rate of 2704 μmol g -1 h -1 under visible light irradiation (λ ≥ 420 nm), which is nearly 11-fold that of its pristine counterpart. This work realizes the synergistic effect between morphology tunning and composition tailoring by using biomass template, which shows a great potential in developing efficient metal-free photocatalysts., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Bismuth vanadate (BVO) possesses great potential in photoelectrochemical water splitting application, but still suffers from low charge transfer efficiency as well as poor chemical stability. Herein, we have fabricated a thin NiFe-bimetal-organic framework (NiFe-MOF) layer grafting surface oxygen vacancies enriched BVO photoanode (NiFe-O vac -BVO), which improves the charge separation and transfer efficiency during oxygen evolution process. Meanwhile, the NiFe-MOFs thin layer can not only protect the surface O vac of BVO, but also efficiently inhibits the photocorrosion. As a result, the resultant NiFe-O vac -BVO exhibits good chemical stability and achieves an outstanding photocurrent density of 4.42 ± 0.1 mA·cm -2 at 1.23 V vs reversible hydrogen electrode (RHE), which is 3.7-time higher than that of BVO photoanode. This work supplies an efficient avenue to design photoanode with enhanced photocurrent and stability by using a thin NiFe-MOF layer grafting O vac -BVO., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Employing perylene diimide supermolecule (PDI) as metal-free cocatalyst, a novel PDI/g-C 3 N 4 /Bi 2 WO 6 (PCB) photocatalyst was constructed for the effective degradation of antibiotics. Both the photocatalytic activity and photostability of g-C 3 N 4 /Bi 2 WO 6 (gCB) were further improved after loading PDI. Under simulated sunlight illumination, the apparent rate constant of tetracycline (TC) degradation by PCB reached 2.6 times that of gCB. The photocatalytic activity of PCB still kept over 80% after 4 cycle experiments, while gCB only remained around 21%. The superior activity of PCB was ascribed to the synergism between the extended visible light absorption range through the participation of PDI cocatalyst and facilitated gCB-to-PDI photoelectron transfer. TC would finally be transformed into non-toxic ring opening products and mineralized. This work demonstrated that PDI was an excellent metal-free cocatalyst and exhibited great potential to boost the activity of photocatalysts., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The flaky carbon nitride containing nitrogen defects (NDCN) could effectively perform the photocatalytic reduction of carbon dioxide (CO 2 ) due to its abundant active sites. Reducing the recombination of electrons and holes was also a method of semiconductor photocatalyst design. A nanosphere ball-flower Indium sulfide (In 2 S 3 ) was synthesized via a simple hydrothermal approach, and then calcined to obtain the β-In 2 S 3 /NDCN heterojunction photocatalyst and applied for CO 2 photocatalytic reduction. The best total yield (carbon monoxide, CO: 20.32 μmol·g -1 ·h -1 ; methane, CH 4 : 2.12 μmol·g -1 ·h -1 ) could be obtained at the optimized 20% β-In 2 S 3 /NDCN under near room temperature and pressure and without using any sacrificial agents or promoters, almost 1.7 times higher compared with NDCN. The composite catalyst still exhibited excellent stability after four cycles. The improvement of excellent performance was due to not only the enhancement of fine CO 2 adsorption/activation and the light absorption ability, but also attributed to the formation of heterojunction, which accelerated the effective separation of electrons and holes. This work might provide a novel approach to design carbon nitride heterojunction photocatalysts with nitrogen defects for CO 2 utilization., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The rapid recombination of photoinduced charge carriers and low selectivity are still challenges for the CO 2 photoreduction. Herein, we proposed that ZIF-67-derived Co 3 O 4 hollow polyhedrons (CoHP) were embedded into NaCl-template-assisted synthesized 3D graphitic carbon nitride (NCN), subsequently, loading Ag by photo-deposition as efficient composites (CoHP@NCN@Ag) for CO 2 photoreduction. This integration simultaneously constructs two heterojunctions: p-n junction between Co 3 O 4 and g-C 3 N 4 and metal-semiconductor junction between Ag and g-C 3 N 4 , in which Co 3 O 4 and Ag serve as hole (h + ) trapping sites and electron (e - ) sinks, respectively, achieving spatial separation of charge carriers. The donor-acceptor structure design of NCN realize a good photogenerated e - -h + separation efficiency. The mesoporous structure of hollow Co 3 O 4 facilitate gas-diffusion efficiency, light scattering and harvesting. And the introduction of plasmonic Ag further strengthens the light-harvesting and charge migration. Benefiting from the rational design, the optimized ternary heterostructures exhibit a high CO 2 -CO yield (562 μmol g -1 ), which is about 4-fold as high as that of the NCN (151 μmol g -1 ). Moreover, the conjectural mechanism was systematically summarized. We hope this study provides a promising strategy for designing efficient g-C 3 N 4 systems for the CO 2 photoreduction., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Exploiting highly-efficient and metal-free photocatalyst for CO 2 conversion into useful chemicals is a promising pathway to solve the energy and environmental crises. In this work, through a facile exfoliation process, an ultra-thin and short-range order g-C 3 N 4 nanosheet with rich terminal oxygen defects is successfully constructed, which presents total electron yield of 36.30 μmol g -1 h -1 , 3.05 times higher than that of bulk one. The results affirms that both the van der Waals forces between the C 3 N 4 layers and the CN bonds on the periodic heptazine units could be disrupted during the sonication process, thus achieving the ultra-thin and ultra-small g-C 3 N 4 nanosheet, which enables the improvement of optical absorption and carrier separation abilities. The π-conjugated triazine rings structure is still remained but the terminal active C radicals tend to transform into oxygen defects which become the sites to bind and activate CO 2 . The in-situ DRIFTS provides the direct evidence that the size regulation and oxygen-defects design strategy can effectively promote the CO 2 adsorption and activation process upon the photocatalyst, thus turning out to boost the reactivity toward CO 2 ., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The development of highly-efficient photocatalyst for H 2 production integrated with microplastic degradation is significant to meet the demand for clean energy and resolve "white pollution". Herein, a series of MXene/Zn x Cd 1-x S photocatalysts were successfully fabricated for H 2 evolution integrated with degradation of polyethylene terephthalate (PET). The resultant photocatalysts exhibited excellent photocatalytic performance, and the best photocatalytic H 2 evolution rate can reach 14.17 mmol·g -1 ·h -1 in alkaline PET alkaline solution. What's more, the PET was also converted to the useful organic micromolecule, including glycolate, acetate, ethanol, etc. The highly-efficient photocatalytic performance of MXene/Zn x Cd 1-x S photocatalysts can be attributed to the enhanced separation ability of photocarriers and optimum band structure with enhanced oxidation capacity of valence band. Finally, the photocatalytic mechanism was investigated in detail. Overall, this work supplied a new useful guidance for solving the energy problem and microplastic pollution issues, simultaneously., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Sodium doped flaky carbon nitride (g-C 3 N 4 ) with nitrogen defects (bmw-DCN-x) were synthesized via two steps method to enhance photocatalytic reduction of carbon dioxide (CO 2 ). After ball milling and calcination, dicyandiamide was evenly dispersed on the sodium chloride (NaCl) template to form a flaky structure. The NaCl not only provided part of sodium (Na) source for Na doped g-C 3 N 4 , but also introduced a large number of nitrogen (N) defects. Meanwhile, sodium hydroxide (NaOH) significantly enhanced Na doping. The bmw-DCN-30, a proportion of modified g-C 3 N 4 , showed heightened photo-reduction CO 2 performance, with satisfactory carbon monoxide (CO) and methane (CH 4 ) productivity at a rate of 30.6 μmol·g -1 ·h -1 and 5.4 μmol·g -1 ·h -1 respectively. This productivity was 15 and 11 times as much as that of bulky g-C 3 N 4 (BCN). The related characterizations confirmed that N defects produced more reactive sites and enhanced the adsorption capacity of carbon nitride to CO 2 . The accompanying Na doping and flaky structure characteristics improved the optical absorption ability and the effective separation of photogenerated carriers. Accordingly, this work provides further insights into constructing modified materials based on carbon nitride for CO 2 reduction., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier Inc.)

Design of highly active and stable non-precious electrocatalysts towards hydrogen evolution reaction (HER) is a hot research topic in low cost, clean and sustainable hydrogen energy field, yet remaining the important challenge caused by the sluggish reaction kinetics for water-alkali electrolyzers. Herein, a robust electrocatalyst is proposed by designing a novel sub-nanometer of copper and ruthenium bimetallic phosphide nanoclusters (Ru x Cu y P 2 ) supported on a graphited carbon nanofibers (CNF). Uniform Ru x Cu y P 2 (~1.90 nm) on the surface of CNF are obtained by introducing the dispersed Ru, thereby improving the intrinsic activity for HER. On optimizing the Ru ratio, the (x = y = 1) RuCuP 2 /CNF catalyst exhibits an excellent HER electroactivity with an overpotential of 10 mV in 1.0 M NaOH electrolyte to produce 10 mA cm -2 current density, which is lower than commercial 20% Pt/C in alkaline solution. Moreover, the kinetic study demonstrated that electrochemical activation energies for HER of RuCuP 2 /CNF is 20.7 kJ mol -1 highest among different ratio bimetallic phosphide. This simple, cost-effective, and environmentally friendly methodology can pave the way for exploitation of bimetallic phosphide nanoclusters for catalyst design., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

In this study, a novel ternary Z-scheme Graphite-like Carbon Nitride (g-C 3 N 4 )/Silver (Ag)/Silver Phosphate (Ag 3 PO 4 ) photocatalyst was designed and prepared using a two-step method (sodium chloride (NaCl) template-assisted strategy plus selective deposition). Its photocatalysts performance against removing 400 ppm of Nitric Oxides (NOx) was then investigated. We found 50 wt% g-C 3 N 4 /Ag/Ag 3 PO 4 (AP-CN 2:1) catalyst removes up to 74% of NO in 90 min under the illumination of visible light (>420 nm), which is respectively 3.5 and 1.8 times higher than using g-C 3 N 4 or Ag 3 PO 4 , alone. This improved performance was attributed to the formation of Z-scheme g-C 3 N 4 /Ag/Ag 3 PO 4 heterojunction, driven by the built-in electric field across the g-C 3 N 4 /Ag/Ag 3 PO 4 interface. These separated the electron-hole but enhanced the original strong oxidation and reduction performance of related components. The superior performance is also attributed to the improved surface area, enhanced hydrophilicity (H 2 O 2 ) and better visible-light-harvesting capability of the composite compound. More importantly, the AP-CN 2:1 sample maintained a NO removal rate of more than 73% even after four rounds of recycling. The photocatalytic oxidation removal mechanism was evaluated using the radical-capture experiments, electron spin resonance (ESR) and ion-exchange high-performance liquid chromatography (HPLC) analysis. The findings of this work offer a simple but effective design of a highly reactive and practical ternary Z-scheme heterojunction photocatalysts for the removal of toxic NO., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Inc.)

Constructing an efficient photocatalyst is critical for photocatalytic carbon dioxide (CO 2 ) into valuable fuel. Herein, a high-efficiency catalyst was synthesized by a simple one-step electrostatic self-assembly method, in which Ti 3 C 2 (TC) was anchored on porous g-C 3 N 4 (PCN) with rich -NH x via NH x -Ti bond. Such a chemical interaction made the optimized TC/PCN-2 with 2 wt% loading of Ti 3 C 2 possess highest CH 4 production (0.99 μmol·h -1 ·g -1 catalyst ) under visible light (>420 nm), which was 14 times higher than that of pure PCN (0.07 µmol·h -1 ·g catalyst -1 ) at the same condition. More importantly, the TC/PCN-2 photocatalyst still maintained satisfied activity after four cycles. Besides the formation of NH x -Ti chemical bonding and superior conductivity of Ti 3 C 2 as a co-catalyst, which facilitated interfacial charges separation and migration, the exceptional performance could also attribute to the enhanced CO 2 adsorption/activation and improved light-harvesting capability. This work provided a potential application in energy conversion with MXene as an efficient co-catalyst., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The effect of self-doping Ti 3+ into V 2 O 5 /TiO 2 catalysts on the activity of the catalysts was assessed by the selective catalytic reduction of NO X with NH 3 (NH 3 -SCR). 0.2-V 2 O 5 /TiO 2 (Al(acac) 3 :TBOT = 0.2%) catalyst had the highest catalytic activity at low-temperature range. The as-prepared catalysts are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), H 2 temperature-programmed reduction (H 2 -TPR), NH 3 temperature-programmed desorption (NH 3 -TPD), surface area and pore structure. XPS and EPR were used to confirm the existence of Ti 3+ and oxygen vacancy in the catalysts. The specific surface area, surface acidity, reducibility and valence state of the active components of the catalysts are significantly affected by the self-doping of Ti 3 +. This work would lead to a new strategic design of Ti 3+ self-doped catalysts with fine structure and that can efficiently improve low-temperature SCR performance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Lanthanum manganite (LaMnO 3 ) with magnesium (Mg) substituted the A- and B-sites were reported for the first time in this work. The Mg substituted LaMnO 3 catalysts were prepared by means of citric acid sol-gel method. The impact of partial substitution of Mg and its substitution site on the catalytic performance of LaMnO 3 in nitric oxide (NO) oxidation was investigated. Through series of characterizations, it was found that Mg substitution at both A- and B-sites improves the specific surface area, Mn 4+ content, reactivity of surface oxygen species, redox property and NO adsorption capacity of LaMnO 3 . However, Mg substitution at the A-site of LaMnO 3 can cause the total charge imbalance of B-site, which significantly improves the amount and reactivity of surface active oxygen species. Therefore, the catalytic activity of the samples decreases in the order: La 0.9 Mg 0.1 MnO 3  > LaMn 0.9 Mg 0.1 O 3  > LaMnO 3 . This study will shed more light on the fundamental understanding and designing of perovskite catalyst., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The supercapacitive performance of high-rate capacity and long-term cycling stability is still a big challenge for electroactive materials. Herein, Ni and Zn co-substituted Co carbonate hydroxide (NiZn-CoCH) flowers array is self-assembled on nickel foams (NFs) using l-ascorbic acid as a nanostructure inducer. The NiZn-CoCH flowers, consisting of silk-like nanosheets, are deservedly large electrode-electrolyte contact area and suitable ion-diffusion channel. The nanostructure and Ni and Zn co-substitution significantly improve energy storage performance. This electrode exhibits a high specific capacitance of 2020.8 F g -1 at 1 A g -1 with high-rate capacity (remain 80.2% at 10 A g -1 ) and 5000-cycle stability (almost unchanged after 1500 cycles at 10 A g -1 ). Additionally, an assembled asymmetric supercapacitor (ASC) device of NiZn-CoCH//activated carbon (AC) achieves a high energy density of 29.6 Wh kg -1 at a power density of 375 W kg -1 and only a 0.5% decrease of the capacitance after 2500 cycles. This facile and novel preparation method, using l-ascorbic acid, may be promising for industrial production of electroactive materials for the high-performance energy storage and conversion devices., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Inc.)

A series of amorphous TiO 2 /NH 2 -MIL-125(Ti) (Am-TiO 2 /NM) composites were in-situ fabricated via one-pot facile water (H 2 O) bath method. The photocatalytic performance of as-synthesized samples was evaluated by CO 2 reduction with H 2 O under visible-light irradiation. The Am-TiO 2 /NM with 22.6 wt% Am-TiO 2 loading had the highest photo activity for CO 2 reduction into CH 4 (1.18 μmol·h -1 ·g -1 catalyst ), which was 1.7 times higher than that of pure NM. The enhanced photocatalytic activity was attributed to the formation of the strong interactions between NM and Am-TiO 2 , which not only improved the ability of electron transfer, but also inhibited the recombination of electron-hole pairs. Furthermore, the optimum sample showed satisfied stability within five times recycling tests during the photo reaction under visible-light irradiation. These kinds of MOF-based composites provided potential applications in the field of energy conversion., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Reasonably designing self-supported metal-organic framework (MOF) nanoarrays is profound for applications in energy storage and conversion. Herein, we construct a triangle-like nickel-cobalt bimetallic metal-organic framework nanosheet array on nickel foam (NiCo-MOF/NF) via facile one-step hydrothermal reaction, served as battery-like electrode material for hybrid supercapacitors. By adjusting the molar ratio of Ni and Co, the optimal NiCo-MOF/NF with Ni/Co = 3:2 (3-2 NiCo-MOF/NF) produces an impressive specific capacity of 1003.5 C/g (2230 F/g) at 1 A/g, surpassing most of the previously reported MOF based electrode materials. The superior electrochemical performances may be related to their 3D well-aligned MOF nanosheets arrays, which provides enlarged electroactive areas. Meanwhile, the tight junction of electrode materials and conductive substrate nickel foam (NF) can guarantee their sufficient electric contact, contributing to fast electron transfer from electrodes to conductive substrates. Finally, a hybrid supercapacitor fabricated by the 3-2 NiCo-MOF/NF against active carbon (AC) delivers an advantageous energy density of 34.3 Wh/kg at a power density of 375 W/kg. These results certificate that such bimetallic NiCo-MOF nanosheets arrays hold great potential as novel electrode materials for hybrid supercapacitors., (Copyright © 2019 Elsevier Inc. All rights reserved.)

In the present study, the ZnO-porous carbon (ZnO-C) composites were prepared by pyrolyzing MOF-74 (Zn) precursor at different pyrolysis temperatures. The ZnO-C composites were endowed with ultrafast organic dye adsorption capability and promising supercapacitance properties due to the existence of abundant pores within the composite structures. Having a surface area of 782.971 m 2 /g and pore volume of 0.698 m 3 /g, the composite pyrolyzed at 1000 °C (ZnO-C1000) exhibited the best performance for organic pollutant uptake. Specifically, 50 mg of ZnO-C1000 could remove all the Rhodamine B dye from 100 mL aqueous solution within 0.5 h even the dye concentration was as high as 40 mg/L. It was also shown that the ZnO-C composites could preserve their adsorption capability in a wide pH range, and keep promising dye adsorption stability after consecutive adsorption/desorption cycles. Furthermore, the ZnO-C900 exhibited a specific capacitance of 197.84 F/g as the supercapacitance electrode with good stability (∼97.8% capacitance retention after 1000 cycles). The overall results indicate that the prepared ZnO-C composites have multi-application potentials which can be utilized as efficient pollutant absorbents as well as electrode materials for supercapacitors., (Copyright © 2019 Elsevier Inc. All rights reserved.)

A series of P doped TiO 2 nanotubes (P-TNTs) catalysts were prepared for photocatalytic oxidation (PCO) of NO. Compared with TiO 2 nanotubes, P-TNTs catalysts exhibited excellent catalytic activity. We confirmed that P was doped into TiO 2 nanotubes lattice by XRD, Raman and TEM characterization. It was found that the enhanced PCO performance of NO was not attributed to the photoelectric properties of the P-TiO 2 from UV-vis, Mott-Schottky and transient photocurrent response results. Therefore, we focused on the studies of catalyst reaction process and reactant adsorption characteristics. The results of transient reactions showed that the catalytic reaction proceeded via a mixed mechanism of Langmuir-Hinshelwood (L-H) and Eley-Rideal (E-R) on the P-TiO 2 catalyst. In addition, P doping was beneficial to the adsorption of H 2 O 2 and NO, which is ascribed to the improved PCO performance of NO., (Copyright © 2019. Published by Elsevier Inc.)

In this work, novel (CeO 2 ) x -(CePO 4 ) 1-x (defined as Ce x P 1-x ) nanorod composites were prepared by a simple co-precipitation method, and the influence of CeO 2 on the catalytic performance of CePO 4 for selective catalytic reduction of NO by NH 3 (NH 3 -SCR of NO) was investigated. The catalytic performance evaluation revealed that the Ce x P 1-x catalysts, especially Ce 0.2 P 0.8 exhibited a much better catalytic activity and H 2 O + SO 2 resistance than CePO 4 . Structure characterizations via high-resolution transmission electron microscope (HRTEM) and Brunauer-Emmett-Teller (BET) revealed that the introduction of CeO 2 had a little effect on the shape of CePO 4 nanorods and it could promote the formation of new mesoporous then significantly enhance the surface area of catalyst. The analysis results of active sites suggested that phosphorus was the main adsorption site for NH 3 and the redox sites were controlled by CeO 2 on Ce x P 1-x catalysts. Finally, reaction process study demonstrated that the NH 3 -SCR over Ce x P 1-x was processed via Langmuir-Hinshelwood (L-H) mechanism. Combining the results of active sites and reaction mechanism analysis, it was drawn that the superior low temperature activity of Ce x P 1-x could be attributed to its excellent redox properties, which promoted the oxidation of NO then facilitated the process of NH 3 -SCR via "fast SCR"., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Semiconductor photocatalysis has become the focus of recent research on antibiotic treatment because it is a green and efficient technology. In this study, α-GaOOH with several novel microstructures has been synthesized at a low temperature and its subsequent thermal transformation. The influence of pH on the synthesis of α-GaOOH is studied, and the results indicate that pH played an important role in the microstructures of α-GaOOH and β-Ga 2 O 3 . All Ga 2 O 3 samples possess macro-mesoporous network structures and exhibits a remarkable photocatalytic activity for antibiotic degradation. The photoelectron chemical tests show that the separation efficiency of photogenerated charge carriers of Ga 2 O 3 -7.0 is higher than that of other Ga 2 O 3 . The enhanced photocatalytic activity of Ga 2 O 3 -7.0 is mainly ascribed to its morphology and oxygen vacancy. The active species trapping and photoluminescence measurement experiments indicate that OH and O 2 - are the major active species contributing to the photocatalytic process. This study will bring about the potential application in treatment of the antibiotic pollutants., (Copyright © 2018 Elsevier Inc. All rights reserved.)

In this paper, a series of catalysts about CeO 2 active sites prepared using reduced TiO 2 (TiR) as supports were firstly used for selective catalytic reduction (SCR) of NO by NH 3 . The catalytic performance evaluation results showed that the NO removal efficiency of CeO 2 /TiR (CeTiR) was much higher than that of CeO 2 /TiO 2 (CeTi). Hence, the aim of this study was to investigate the promotion mechanism of catalytic performance of CeTiR catalysts. The catalysts were characterized by XRD, BET, Raman, XPS, NH 3 -TPD and H 2 -TPR. The results of characterization revealed that CeO 2 had a strong interaction with oxygen vacancies of TiR supports. The strong interaction resulted in more Ce 3+ formation and better redox properties for CeTiR catalysts. In addition, it was confirmed that the better redox properties of CeTiR could be considered as the major reason of its high SCR activity via L-H mechanism but not acid properties. We expected that this study could shed some lights on the development of SCR catalysts for improving the interaction between Ti support and active species for enhancing SCR reaction., (Copyright © 2017 Elsevier Inc. All rights reserved.)

This study aimed at investigating the reason of high catalytic activity for CeO2-WO3/TiO2 catalyst from the aspects of WO3 interaction with other species and the NO oxidation process. Analysis by X-ray diffractometry, photoluminescence spectra, diffuse reflectance UV-visible, X-ray photoelectron spectroscopy, density functional theory calculations, electron paramagnetic resonance spectroscopy, temperature-programmed-desorption of NO and in situ diffuse reflectance infrared transform spectroscopy showed that WO3 could interact with CeO2 to improve the electron gaining capability of CeO2 species. In addition, WO3 species acted as electron donating groups to transfer the electrons to CeO2 species. The two aspects enhanced the formation of reduced CeO2 species to improve the formation of superoxide ions. Furthermore, the Ce species were the active sites for the NO adsorption and the superoxide ions over the catalyst needed oxidizing the adsorbed NO to improve the NO oxidation. This process was responsible for the high catalytic activity of CeO2-WO3/TiO2 catalyst., (Copyright © 2015 Elsevier Inc. All rights reserved.)

A V2O5/N-doped TiO2 catalyst has been developed by partly substituting the lattice oxygen of TiO2 support with nitrogen, which showed a remarkable increase in activity for the reduction of NO with NH3 at low temperature. The catalyst was characterized by Brunauer-Emmett-Teller (BET), transmission electron microscope (TEM), photoluminescence (PL), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR). The results demonstrated that N doping cannot noticeably change the microscopic features but dramatically enhanced the formation of surface oxygen vacancies, which can play a vital role in the formation of superoxide ions to improve the SCR activity. The catalyst with [N]/[Ti]=1.0×10(-2) showed the highest NO removal efficiency in the SCR reaction at low temperature. Furthermore, the V1TiN1.0 catalyst showed better resistance to SO2 and H2O during the SCR of NO., (Copyright © 2012 Elsevier Inc. All rights reserved.)

A mathematical model was developed to quantitatively analyze the rheological data of rennet casein gelation at different cooling rates. Kinetic parameters were estimated and correlated with the microstructure development of the protein network. The kinetic model identified structure development upon cooling to be first order, and the network forming energies were estimated for four protein concentrations cooled at four rates. A lower energy for network formation was observed for a slower cooling rate and a higher protein concentration. This observation resulted from the availability of more flocs at a slower cooling rate and a higher casein concentration, simplifying floc cross-linking. By analyzing the kinetics during the aging process of casein gels, no difference in the reaction mechanism was observed. This study illustrated that structure formation resulted from the addition of flocs into the protein network: not all flocs were part of the network at a defined gel point. The incubation period following cooling integrated idle flocs into the network, thereby strengthening the gel. By understanding the gelation mechanism during cooling of rennet casein gels, the structure and thus quality of dairy products, such as processed cheese, may be better controlled.