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The proton transfer reaction H3+ + CO → H2 + HCO+/HOC+ is of great importance in interstellar and circumstellar environments. The dynamics and kinetics of the reaction were studied using the quasiclassical trajectory approach on a newly developed ab initio potential energy surface (PES) for the ground electronic state. The PES was constructed by fitting 46 462 ab initio points at the level of CCSD(T)-F12a/aug-cc-pVTZ using the fundamental invariant-neural network method. The calculated product branching ratio, scattering angular distribution, and thermal rate coefficient agreed reasonably well with the experimental measurements, which were rationalized by the underlying reaction mechanisms. [ABSTRACT FROM AUTHOR]

• Fundamentals of heterogeneous photo-activated oxidant processes were introduced. • Difference and comparability of photo-activated mechanism were summarized. • Quantitative and qualitative analytic means of reactive species were compared. • Synergy between photocatalysis and oxidant activation was case-by-case discussed. • Challenges of coupled techniques for water decontamination were proposed. The rising debate on the dilemma of photocatalytic water treatment technologies has driven researchers to revisit its prospects in water decontamination. Nowadays, heterogeneous photocatalysis coupled oxidant activation techniques are intensively studied due to their dual advantages of high mineralization and high oxidation efficiency in pollutant degradation. This paved a new way for the development of solar-driven oxidation technologies. Previous reviews focused on the advances in one specific coupling technique, such as photocatalytic persulfate activation and photocatalytic ozonation, but lack a consolidated understanding of the synergy between photocatalytic oxidation and oxidant activation. The synergy involves the migration of photogenerated carriers, radical reaction, and the increase in oxidation rate and mineralization. This review systematically summarizes the fundamentals of activation mechanism, advanced characterization techniques and synergistic effects of coupling techniques for water decontamination. Besides, specific cases that lead researchers astray in revealing mechanisms and assessing synergy are critically discussed. Finally, the prospects and challenges are put forward to further deepen the research on heterogeneous photocatalytic activation of oxidants. This work provides a consolidated view of the existing heterogeneous photocatalysis coupled oxidant activation techniques and inspires researchers to develop more promising solar-driven technologies for water decontamination. [Display omitted] [ABSTRACT FROM AUTHOR]

In establishing the kinetics, energetics and mechanisms of phenolic degradation reactivity, active reactive oxygen species (ROS) on catalysts surface could exert a vital part. This paper attempts to account for different ROS at the atomic level using octahedral layered birnessite-type MnO 2 as a platform with different crystal planes which could induce the Jahn-Teller effect and further realize deep mineralization of phenolic pollutants at low temperature. The catalytic degradation phenol rate of (100) MnO 2 is 3 times as much as that of (001) MnO 2 , and the activation energy of the catalytic reaction is reduced by 11 KJ/mol. The degradation content of (100) MnO 2 surpasses 30% than that of (001) MnO 2 . Both spin-trapping EPR and DFT results show superoxide ( O 2 − ) species could exist on (001) MnO 2 through one electron transfer, while the peroxide (O 2 2− ) species exist on (100) MnO 2 via two electrons transfer. All the results illustrate that birnessite MnO 2 possesses surface-dependent molecular oxygen activation properties. [ABSTRACT FROM AUTHOR]

The enhancement of mineralization of phenol via photoelectrocatalytic (PEC) degradation of g-C 3 N 4 film under visible light irradiation ( λ > 420 nm) was investigated. The phenol was degraded completely by the g-C 3 N 4 with a 2.5 V bias, and 89.3% of the total organic carbon (TOC) was removed, which was 2.4 times the amount achieved using photocatalytic degradation. The synergistic effect of photoelectrocatalysis was proposed to explain the dramatic enhancement. The visible light irradiation was not only able to eliminate the passivation of the g-C 3 N 4 electrode for the phenol polymer film at potentials below 1.0 V but also generated a promoting effect of electrocatalytic (EC) oxidation at potentials above 1.0 V. The more active substances, such as OH and O 2 − , could be produced under light irradiation promoted the EC oxidation of phenol and the intermediate products. Simultaneously, the applied bias could reduce the recombination of the photogenerated electron–hole pairs, promote the separation of photogenerated charge carriers, and improve the photocatalytic oxidation efficiency of g-C 3 N 4 . [ABSTRACT FROM AUTHOR]

The weak or brittle mechanical properties, icing and water evaporation under very low or high temperatures, the complex preparation process and high costs limited the application of ionic hydrogels and ionogels. Here, we designed and prepared stretchable and multifunctional ionic gels via frontal polymerization (FP) of polymerizable ternary deep eutectic monomers (DEMs) with a long pot life. The highly stretchable ionic gels can be obtained by altering the molar ratio of polymerizable and non-polymerizable hydrogen bond donors (HBDs), acrylamide (AM) and urea (U), together with hydrogen bond acceptor (HBA), choline chloride (ChCl), respectively. FTIR and 1H-NMR spectra were used to characterize the chemical structure of DEM. Preliminary experiment indicated the pot lives of ternary DEM were much longer than that of the corresponding binary DEM without U. The obtained DEMs were investigated for preparing multifunctional ionic gels by FP. As the molar ratio of U to M changed from 0.7:1.3 to 1.3:0.7, the tensile and compressive strength of ionic gel decreased from 225 KPa and 3129 KPa to 24.7 KPa and 210 KPa, respectively. However, the elongation at break of the ionic gel increased from 283% to 680%. After FP, the DES composed of U and ChCl embedded in the cross-linked PAM not only acted as a plasticizer, but also as a conductive and anti-freezing agent of ionic gels. This work provides a rapid, green and low energy consumption method to construct stretchable, conductive, self-healing and anti-freezing ionic gels, which can be used in flexible bio-electronic devices in the future. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotubes (CNTs) were “dissolved” in mixed solution of cyclodextrin (CD) and cyclodextrin prepolymer (pre-CDP) and were used as modifier to fabricate chemical modified electrode. The dispersions of CNTs in different solutions were characterized using UV–vis spectrophotometer. The insoluble conducting composite film of poly-cyclodextrin (CDP) and carbon nanotube was synthesized, and glucose oxidase (GOx) was immobilized on the film to fabricate amperometric biosensor. The CNT–CDP electrode was stable. It can keep the exceptional chemical and physical properties of CNTs and the host–guest chemical reaction ability of cyclodextrins. Cyclic voltammetry measurements of potassium ferricyanide solution (50mM, and scan rate 100mVs−1) shows that the CDP film was compact and the CNT–CDP film maintains the electrocatalytic activity of CNT. Glucose oxidase was used as a model enzyme to prepare a glucose biosensor. The bioactivity of immobilized glucose oxidase was maintained due to the biocompatibility of cyclodextrin. Amperometric measurements were done with different concentrations of glucose. The CNT–CDP/GCE–GOx biosensor has wide concentration ranges and good sensitivity to glucose. It showed a detection limit of 3.5μM with a linear range from 0.004 to 3.23mM and from 4.26 to 10.00mM. In addition, the biosensor can be operated under wide pH range (pH 5.6–7.8) without great changes in its sensitivity. [Copyright &y& Elsevier]

A high photocatalytic BiPO4 with a novel nonmetal oxy acid structure is synthesized by a hydrothermal method. BiPO4 photocatalyst has an optical indirect band gap of 3.85 eV. In a comparison of BiPO4 with that of TiO2 (P25, Degussa), it is found that the photocatalytic activity of BiPO4 is twice that of TiO2 (P25, Degussa) for the degradation of methylene blue (MB) dye, while the BET surface of BiPO4 is just one tenth of that of P25. Both the high position of the valence band and the high separation efficiency of electron—hole pairs result in the high photocatalytic activity. The inductive effect of PO43- helps the e-/h+ separation, which plays an important role in its excellent photocatalytic activity. It may extend to the synthesis of other inorganic nonmetal salts of oxy photocatalysts with suitable band gap and high activity for the environmental purification of organic pollutants in aqueous solution. [ABSTRACT FROM AUTHOR]

The many-body expansion approach (MBE) is employed to build potential energy surfaces (PESs) for nitrogen clusters, which serve as a possible candidate of high energy density materials. The ground-state global PES of N 4 developed by Truhlar's group is utilized to construct the two-body, three-body, and four-body interaction potentials. The energy of nitrogen clusters is thus obtained by summing the many-body interaction energies up to four-body term. This work found that such a many-body expansion could give reasonable energy predictions for loose chain nitrogen molecules while produce bad predictions for compact structures. The failure is caused by the neglect of high-order (n ≥ 5) n -body interactions that are significant in the bonding area. The difficulties in applying the MBE method to construct the potential energy surface of nitrogen clusters are analyzed. [ABSTRACT FROM AUTHOR]

Abstract: The “unprotected” Pt nanoclusters (average size 2nm) mixed with the nanoscale SiO2 particles (average size 13nm) were used as a glucose oxidase immobilization carrier to fabricate the amperometric glucose biosensor. The bioactivity of glucose oxidase (GOx) immobilized on the composite was maintained and the as-prepared biosensor demonstrated high sensitivity (3.85μAmM−1) and good stability in glucose solution. The Pt–SiO2 biosensor showed a detection limit of 1.5μM with a linear range from 0.27 to 4.08mM. In addition, the biosensor can be operated under wide pH range (pH 4.9–7.5) without great changes in its sensitivity. Cyclic voltammetry measurements showed a mixed controlled electrode reaction. [Copyright &y& Elsevier]

Abstract: ZnWO4 powder photocatalyst was prepared by calcining co-precipitated precursor, and its high photocatalytic activity was revealed. The ZnWO4 crystal phase was formed at 450°C for 4h. The crystal size and particle size of ZnWO4 powder increased with the increasing of calcination temperature and time. At 500°C for 4h, the photocatalyst reaches the highest photocatalytic activity with formaldehyde removal efficiency of 90% within 25min. Moreover, its photocatalytic activity is almost similar to that of P-25 in degradation of gaseous formaldehyde. ZnWO4 also displayed high photocatalytic activity in aqueous solution for degradation of RhB. The high crystallinity and large surface area are responsible for its high photocatalytic activity. [Copyright &y& Elsevier]

Abstract: A wide size range of SiO2 particles were synthesized and were used as enzyme immobilization carriers to fabricate glucose biosensors. The size of the particles was in the range of 17–520nm. These biosensors could be operated under physiological conditions (0.1M phosphate buffer, pH 7.2). Particle size could affect the performance of SiO2 modified glucose biosensors drastically. The smaller particles had higher performance. The smallest SiO2 modified biosensor could work well in the glucose concentration range of 0.02–10mM with a correlation coefficient of 0.9993. Its sensitivity was 2.08μA/mM and the detection limit was 1.5μM glucose. [Copyright &y& Elsevier]

Abstract: A series of monodispersed nano-SiO2 film enhanced glucose biosensors with different thickness were fabricated by using dip-coating method. The suitable thickness of nanosized SiO2 film provided optimal environment for glucose oxidase to retain its bioactivity. A key factor to fabricate high sensitivity glucose biosensor was to enlarge the enzyme loading on the surface. The high surface area of the small nanosized SiO2 particles in the thick film increased the surface enzyme loading, resulting in the high performance of the biosensor. But if the film is too thick, the performance of the sensor would decrease because the mass transfer of glucose and H2O2 became difficulty. The electrochemical response of glucose with the 800nm SiO2-biosensor revealed a linear behavior in the range of 0.005–2.5mM glucose in pH 7.2 phosphate buffer solution. Such a glucose biosensor held its sensitivity as high as 71.1μAmM−1 cm−2 and its detection limit as low as 0.3μM. The good sensor-to-sensor reproducibility also indicates the simpleness and practicability of this kind of biosensor. [Copyright &y& Elsevier]

Abstract: The reaction and poisoning mechanism of organophosphorous gas with LaCoO3 model catalyst have been studied. Organophosphorous gas diffused into LaCoO3 model catalyst and reacted to form some new species such as LaPO4, La4(P2O7)3 and CoO, which resulted in the distortion and destruction of perovskite structure. The residual concentration of phosphorus in the catalyst layer reached a maximum after the catalyst was poisoned at 600°C for 2h. The diffusion depth of phosphorus in LaCoO3 layer increased with poisoning temperature and time. After the model catalyst was poisoned at a high temperature above 700°C or for a longer period, the distribution of phosphorus in the LaCoO3 layer became homogeneous and the distribution peak of P concentration shifted into the layer. The catalytic performance test for oxidation of CO indicated that the formation of phosphate and the destruction of the perovskite structure in LaCoO3 catalyst layer resulted in the deactivation of the perovskite catalyst. [Copyright &y& Elsevier]

LaNiO3 thin film with perovskite structure was successfully prepared on Si (111) substrate via an amorphous heteronuclear complex as precursor. The annealing temperature had a significant effect on the crystallization of LaNiO3 film. The crystallization temperature of the film was higher than that of the powder samples due to the interface reaction between the layer and the substrate. The thickness of LaNiO3 thin film increased with the precursor concentration and the texture of the film could be improved significantly by adding some polyethylene glycol (PEG) as additive. A remarkable decline of the electrical resistivity was observed when the calcination temperature was raised to 800 °C. The conductivity of LaNiO3 film increased gradually when the temperature decreased and the film showed a metallic behavior. [Copyright &y& Elsevier]

Abstract: Nanosized-Ta2O5 powder photocatalyst was successfully synthesized by using sol–gel method via TaCl5 butanol solution as a precursor. Ta2O5 species can be formed under 500°C via the decomposition of the precursor. The crystalline phase of Ta2O5 powder photocatalyst can be obtained after being calcined above 600°C for 4h. The crystal size and particle size of Ta2O5 powder photocatalyst was about 50nm. A good photocatalytic performance for the degradation of gaseous formaldehyde was obtained for the nanosized-Ta2O5 powder. The Ta2O5 powder formed at 700°C for 4h and at 650°C for 12h showed the best performance. The calcination temperature and time play an important role in the crystallization and photocatalytical performance of nanosized-Ta2O5 powder. [Copyright &y& Elsevier]

Abstract: A simple synthetic route in mild condition to obtain nanosized NaTaO3 powder with cubic morphology is reported in which the compound was hydrothermally prepared at 120°C for 12h. The cubic crystalline structure of this nanosized NaTaO3 product was ensured by using XRD and TEM. The band gap of the nanosized NaTaO3 was 3.96eV based on UV spectrum. The hydrothermal process probably follows the dissolution–precipitation mechanism. Also this NaTaO3 powder showed high photoreactivity under UV light in gas phase and liquid phase photoreactions. [Copyright &y& Elsevier]

Perovskite and pyrochlore KTaO3 were selectively synthesized in mixed solvents (water–ethanol and water–hexane systems) by solvothermal reaction with KOH, whose concentration was one order of magnitude lower than that in traditional methods. The samples were characterized by X-ray diffraction and transmission electron microscopy. Results show that the ratio of inert solvents (ethanol or hexane) to active solvent (water) played a significant role in the manipulation of the crystalline behavior of KTaO3 to the form pyrochlore or perovskite nanocrystals. The possible mechanisms of the reactions are also discussed. [Copyright &y& Elsevier]

Nano-crystalline SrAl2O4 with spinel structure was successfully prepared at 700 °C using amorphous SrAl2(diethylenetriaminepentaacetic acid (DTPA)1.6)(H2O)4 as precursor. The precursor was synthesized by a simple inorganic reaction and decomposed into SrAl2O4 at temperatures above 500 °C, which was proved by DTA–TGA and X-ray photoelectron spectroscopy (XPS) analysis. X-ray diffraction (XRD) results illustrated that a crystalline SrAl2O4 phase can form at 700 °C, which is about 600 °C lower than that used in the traditional method. The crystalline SrAl2O4 prepared at 900 °C for 2 h had a crystal size of about 28 nm and a grain size of about 80 nm, and its BET surface area can reach 28.056 m2/g. Calcination temperature and time had a weak effect on crystal size. [Copyright &y& Elsevier]

The application of nanomaterials in the field of optical sensors has become a new, growing area of interest in recent years. We review chemical sensors that apply the optical principles of nanomaterials to the determination of chemical and biochemical analytes. We mainly focus on the changes of spectral absorbance, photoluminescence (PL) and chemiluminescence (CL) phenomena induced by the interaction between nanomaterials and various analytes. [Copyright &y& Elsevier]

SiO2 nanoparticles modified by oleic acid (OA) were prepared using surface-modification method in this work. Infrared spectroscopy (IR), transmission electron microscopy (TEM) and X-ray photoelectron spectra (XPS) were used to investigate the structure of the modified SiO2 nanoparticles. Effects on coverage and dispersion in oil by OA concentration were also studied. The results indicate that OA-modified SiO2 nanoparticles are capable of dispersing stably in mineral oil and the OA is bonded to the surface of SiO2 nanoparticles through esterification. The optimal reaction temperature and the proportion of OA to SiO2 were established. [Copyright &y& Elsevier]

Nanosized La1−xSrxCoO3 (x=0.05, 0.1, 0.6) cobalite oxide powder with perovskite structure was successfully synthesized at a relatively low calcination temperature by using an amorphous heteronuclear complex La1−xSrxCo(DTPA)·6H2O as a precursor. The precursor decomposed completely into cobalite oxide above 600 °C based on the differential thermal analysis (DTA) and thermal gradient analysis (TGA) results. X-ray diffraction (XRD) demonstrated that nanosized La1−xSrxCoO3 crystalline powder with perovskite structure was obtained after the calcination temperature increased to 600 °C. The effects of calcination time and temperature were also examined by XRD and transmission electron microscopy (TEM). The results indicated that the grain size and the crystal size of La1−xSrxCoO3 increased with the calcination temperature from 600 to 800 °C, and were less influenced by the heat-treatment time. It can be concluded that it was a useful way to synthesize nanosized perovskite oxides using an amorphous complex as a precursor, and this method can be easily quantitatively controlled. [Copyright &y& Elsevier]

Mesoporous TiO2 film photocatalysts supported on stainless steel substrates were prepared using the sol–gel method with Ti(OC4H9)4 as a precursor and poly ethylene glycol (PEG) as a structure-directing agent. Mesoporous TiO2 film with a pore diameter of about 15 nm was obtained with the addition of PEG (molecular weight =400). The pore diameter of TiO2film was varied with molecular weight of PEG additive. The structure-directing process was also discussed. Mesoscopically ordered inorganic/polymer composites were believed to form during the process. Compared to conventional TiO2 film photocatalyst, the mesoporous TiO2 film showed a good performance for the photo degradation of rhodamine B (RB) solution irradiated with UV light of 365 nm. The photo degradation constant of rhodamine B for mesoporous TiO2 film photocatalyst can arrive at 22 times of that for conventional TiO2 film photocatalyst. Also an excellent performance for the degradation of gaseous formaldehyde with mesoporous film photocatalyst was obtained. The photo degradation rate of gaseous formaldehyde for mesoporous TiO2 film photocatalyst can arrive at six times of that for conventional TiO2 film photocatalyst. [Copyright &y& Elsevier]

Three photocatalytic oxidation (PCO) systems: C7H16–O2, SO2–O2 and C7H16–SO2–O2 were carried out with the aid of UV-illuminated TiO2 nanoparticles at room temperature in a batch reactor. In C7H16–O2–TiO2 system, no catalyst deactivation was observed, while for SO2–O2–TiO2 and C7H16–SO2–O2–TiO2 systems, the photocatalytic activity of used TiO2 powder showed decreasing and eventually no activity after used consecutively. The reaction products such as sulfur trioxide or sulfuric acid adsorbed onto the surface of TiO2 catalyst were poisoning species. Photocatalytic activity of the deactivated TiO2 powder could be regenerated by sonicating treatment with water and methanol for the two systems, respectively. [Copyright &y& Elsevier]

Nanosized LaCoxMn1−xO3 (x=0.3 and 0.4) oxide with perovskite structure was successfully synthesized at fairly low temperature in air by the decomposition of the amorphous precursor LaCoxMn1−x(DTPA)·6H2O (x=0.3 and 0.4). The precursor could completely decompose into oxide at temperature below 500 °C according to the DTA and TGA results. XPS and XRD demonstrated that the decomposed species was composed of LaCoxMn1−xO3 oxide and a perovskite structure was formed after being calcined at 500 °C for 2 h. TEM showed that LaCoxMn1−xO3 oxide existed as nanoparticles and the dispersion was homogeneous when the precursor was calcined at low temperature. The effect of the calcination temperature on the particle size and the specific surface area was much more serious than that of the calcination time. This method is effective and can be easily quantitatively controlled to synthesize nanosized perovskite oxides. [Copyright &y& Elsevier]

Ionic gels are attracting enormous attention due to their good conductivity and multifunctionality that are required for electronic devices. However, diverse applications require ionic gels whose mechanical properties can be adjusted to satisfy different demands. Herein, we designed and prepared conductive and self-healing ionic gels from deep eutectic monomers (DEMs) with adjustable mechanical properties via frontal polymerization (FP). FTIR and 1H-NMR spectra confirmed that there were the multiple hydrogen bonds in DEMs. The obtained DEMs were investigated for preparing self-healing ionic gels by FP. The FP experiments shown that higher molar ratio of AAc and AM caused a decrease in front velocity (Vf) and maximum front temperature (Tmax), while higher content of crosslinker led to an increase in Vf and Tmax. The mechanical properties of ionic gels can be adjusted by changing the molar ratio of AAc and AM. The tensile strength varied in the range from 0.11 to 0.85 MPa, and compression stress was different from 9.17 to 35.91 MPa (at a compression stress of 80%), respectively. The elongation rate became from 16.13 to 157.56%. The multiple hydrogen bonds in the ionic gels enabled them a rapid self-healing ability. In addition, the ion conductivities of ionic gels improved remarkably after water adsorption. The present study provides a rapid and green strategy to prepare conductive and self-healing ionic gels with turnable mechanical properties, which may inspire more future research studies for flexible electronic materials. [ABSTRACT FROM AUTHOR]

Nature‐inspired supramolecular self‐assemblies are attractive photocatalysts, but their quantum yields are limited by poor charge separation and transportation. A promising strategy for efficient charge transfer is to enhance the built‐in electric field by symmetry breaking. Herein, an unsymmetric protonation, N‐heterocyclic π‐conjugated anthrazoline‐based supramolecular photocatalyst SA‐DADK‐H+ was developed. The unsymmetric protonation breaks the initial structural symmetry of DADK, resulting in ca. 50‐fold increase in the molecular dipole, and facilitates efficient charge separation and transfer within SA‐DADK‐H+. The protonation process also creates numerous active sites for H2O adsorption, and serves as crucial proton relays, significantly improving the photocatalytic efficiency. Remarkably, SA‐DADK‐H+ exhibits an outstanding hydrogen evolution rate of 278.2 mmol g−1 h−1 and a remarkable apparent quantum efficiency of 25.1 % at 450 nm, placing it among the state‐of‐the‐art performances in organic semiconductor photocatalysts. Furthermore, the versatility of the unsymmetric protonation approach has been successfully applied to four other photocatalysts, enhancing their photocatalytic performance by 39 to 533 times. These findings highlight the considerable potential of unsymmetric protonation induced symmetry breaking strategy in tailoring supramolecular photocatalysts for efficient solar‐to‐fuel production. [ABSTRACT FROM AUTHOR]

Nature‐inspired supramolecular self‐assemblies are attractive photocatalysts, but their quantum yields are limited by poor charge separation and transportation. A promising strategy for efficient charge transfer is to enhance the built‐in electric field by symmetry breaking. Herein, an unsymmetric protonation, N‐heterocyclic π‐conjugated anthrazoline‐based supramolecular photocatalyst SA‐DADK‐H+ was developed. The unsymmetric protonation breaks the initial structural symmetry of DADK, resulting in ca. 50‐fold increase in the molecular dipole, and facilitates efficient charge separation and transfer within SA‐DADK‐H+. The protonation process also creates numerous active sites for H2O adsorption, and serves as crucial proton relays, significantly improving the photocatalytic efficiency. Remarkably, SA‐DADK‐H+ exhibits an outstanding hydrogen evolution rate of 278.2 mmol g−1 h−1 and a remarkable apparent quantum efficiency of 25.1 % at 450 nm, placing it among the state‐of‐the‐art performances in organic semiconductor photocatalysts. Furthermore, the versatility of the unsymmetric protonation approach has been successfully applied to four other photocatalysts, enhancing their photocatalytic performance by 39 to 533 times. These findings highlight the considerable potential of unsymmetric protonation induced symmetry breaking strategy in tailoring supramolecular photocatalysts for efficient solar‐to‐fuel production. [ABSTRACT FROM AUTHOR]

Constructing an internal electric field (IEF) within the hematite (Fe2O3) photoanode for highly efficient water oxidation performance with facilitated charge transfer and separation remains still a significant challenge. Unlike the conventional approach of creating interfacial electric fields through heterojunction design by introducing another semiconductor, a novel strategy is proposed for engineering localized n‐p homojunctions on the surface of Fe2O3 photoanode using gradient Zn2+ doping strategy. By implementing this approach, the inherent n‐type characteristics of Fe2O3 can be transformed into p‐type, thereby facilitating the formation of an n‐p junction with robust IEF, which enables more efficient charge separation and transfer. Additionally, the gradient Zn2+ doping is accompanied by the generation of oxygen vacancies, which further improves the charge transfer efficiency and accelerates water oxidation kinetics. As expected, the photocurrent density of optimized Fe2O3 photoanode at 1.23 V versus reversible hydrogen electrode is ≈2.6‐fold that of Fe2O3. This work provides a novel perspective on the design of localized n‐p homojunction within photoanodes for achieving high solar energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Organic polymer photocatalysts are a promising material platform for photosynthetic hydrogen peroxide production from water and oxygen. However, limited by the controlled structural design and lack of effective active sites, their photocatalytic efficiency is unsatisfactory. To address these above issues, we precisely designed and prepared two alkyne-based porous polymers via the Sonogashira cross-coupling reaction (POP-DT and POP-DF). Acetylene served as the oxygen-reducing active site, tuning the thiophene or furan ring as the electron donor unit. They exhibited a large specific surface area and rich pore architecture. Under visible light irradiation, the H2O2 generation rate of POP-DT was as high as 2422.2 μmol g−1 h−1, which was 4.3 times higher than that of POP-DF, representing one of the best performances ever reported for polymeric photocatalysts. We found that the combination of acetylene and thiophene resulted in faster charge separation and transfer efficiency, significantly improving the kinetic behaviour of the oxygen reduction reaction. More importantly, combined with in situ diffuse reflectance infrared Fourier transform spectroscopy and theoretical calculations, we demonstrate that acetylene-connected thiophene is more beneficial to the electron enrichment of the acetylene active site, enhancing the adsorption and activation of oxygen, thus boosting the photocatalytic efficiency for the oxygen reduction reaction. Our work provides a novel strategy for designing advanced polymer photocatalysts for enhanced solar energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Investigating the catalytic behavior of the liquid fuels on well‐defined dual sites is crucial in understanding electrocatalytic reactions. Herein, concept holding bidirectional electronegativity dominant d‐band center regulation on Pt‐Rh dual sites is proposed to tailor the catalytic behaviors toward methanol oxidation reaction (MOR). The Pt‐Rh dual sites are engineered by introducing the low‐electronegativity Ga/Ni and high‐electronegativity W elements in PtRhGaNiW high‐entropy alloy (HEA), which can drive the electron cloud of Pt‐Rh dual sites redispersing over a wide orbit window. The optimized Pt‐Rh dual sites in PtRhGaNiW HEA nanowire achieve a high current density of 5.61 mA cm−2 toward MOR, which is 3.38 and 9.75 times than that of PtRh alloy (1.66 mA cm−2) and Pt/C (0.57 mA cm−2), as well as remarkably stability and COads poisonous resistance. The theoretical calculations further disclose that the redistribution of surface localized electron around Pt‐Rh dual sites can promote direct oxidation of ─OH, and accelerate the COads oxidation/removal. This work presents a breakthrough in designing advanced dual site electrocatalysts for complex catalytic reactions. [ABSTRACT FROM AUTHOR]

Photocatalytic uranium extraction from seawater is an ideal strategy to obtain uranium resources. Herein, the cyano‐functionalized graphitic carbon nitride (g‐C3N4‐CN) with an isosite structure of adsorption and photoreduction for U(VI) is successfully prepared to achieve efficient photocatalytic uranium extraction from seawater. As the key of the isosite structure, the cyano group not only dramatically promotes the separation of photogenerated charges of g‐C3N4‐CN and enriched electrons around it, but also greatly improves the adsorption capacity and selectivity for U(VI) over g‐C3N4‐CN by complexing with U(VI). Therefore, g‐C3N4‐CN exhibits efficient and stable photocatalytic U(VI) reduction performance, with a saturated uranium extraction capacity of 2644.3 mg g−1, significantly higher than most reported g‐C3N4‐based photocatalysts. Moreover, it also performs well in solar light‐driven uranium extraction from actual seawater. Briefly, this work illustrates the importance of constructing the isosite structure of adsorption and photoreduction for U(VI) in improving the photocatalytic uranium extraction performance. [ABSTRACT FROM AUTHOR]

Heterocycle‐linked phthalocyanine‐based COFs with close‐packed π–π conjugated structures are a kind of material with intrinsic electrical conductivity, and they are considered to be candidates for photoelectrical devices. Previous studies have revealed their applications for energy storage, gas sensors, and field‐effect transistors. However, their potential application in photodetector is still not fully studied. The main difficulty is preparing high‐quality films. In our study, we found that our newly designed benzimidazole‐linked Cu (II)‐phthalocyanine‐based COFs (BICuPc‐COFs) film can hardly formed with a regular aerobic oxidation method. Therefore, we developed a transfer dehydrogenation method with N‐benzylideneaniline (BA) as a mild reagent. With this in hand, we successfully prepared a family of high crystalline BICuPc‐COFs powders and films. Furthermore, both of these new BICuPc‐COFs films showed high electrical conductivity (0.022–0.218 S/m), higher than most of the reported COFs materials. Due to the broad absorption and high conductivity of BICuPc‐COFs, synaptic devices with small source‐drain voltage (VDS=1 V) were fabricated with response light from visible to near‐infrared. Based on these findings, we expect this study will provide a new perspective for the application of conducting heterocycle‐linked COFs in synaptic devices. [ABSTRACT FROM AUTHOR]

Heterocycle‐linked phthalocyanine‐based COFs with close‐packed π–π conjugated structures are a kind of material with intrinsic electrical conductivity, and they are considered to be candidates for photoelectrical devices. Previous studies have revealed their applications for energy storage, gas sensors, and field‐effect transistors. However, their potential application in photodetector is still not fully studied. The main difficulty is preparing high‐quality films. In our study, we found that our newly designed benzimidazole‐linked Cu (II)‐phthalocyanine‐based COFs (BICuPc‐COFs) film can hardly formed with a regular aerobic oxidation method. Therefore, we developed a transfer dehydrogenation method with N‐benzylideneaniline (BA) as a mild reagent. With this in hand, we successfully prepared a family of high crystalline BICuPc‐COFs powders and films. Furthermore, both of these new BICuPc‐COFs films showed high electrical conductivity (0.022–0.218 S/m), higher than most of the reported COFs materials. Due to the broad absorption and high conductivity of BICuPc‐COFs, synaptic devices with small source‐drain voltage (VDS=1 V) were fabricated with response light from visible to near‐infrared. Based on these findings, we expect this study will provide a new perspective for the application of conducting heterocycle‐linked COFs in synaptic devices. [ABSTRACT FROM AUTHOR]

Solar‐driven photocatalytic oxygen reduction is a promising pathway for sustainable hydrogen peroxide (H2O2) production. However, limited O2 diffusion and low selectivity in the two‐electron oxygen reduction reaction hinder its practical application. Here, a novel conjugated organic polymer material (conjugated triazine‐thiophene polymer, CTTP) based on triazine and thiophene, integrating a favorable mass transfer structure with competent catalytic centers is presented for the first time. Remarkably, under the gas–liquid–solid triphase condition, the self‐floating CTTP can rapidly capture gaseous oxygen, reducing it to superoxide radicals and transferring them to the reaction interface, drastically enhancing H2O2 yield. An excellent H2O2 concentration of 1.85 mm g−1 h−1 is achieved in a triphase system, representing a remarkable 14‐fold improvement compared to the liquid and solid phase reaction. Interestingly, the triphase system based on CTTP demonstrates the potential for large‐scale H2O2 production under 8 h of sunlight irradiation, reaching 293 ppm day−1 m−2. This work opens up a new avenue for the construction of sustainable H2O2 production systems and may stimulate future related research. [ABSTRACT FROM AUTHOR]

Hydrogen-transfer reactions take place in a wide range of chemically active environments. In this work, thermal rate coefficients of the prototypical hydrogen-transfer reaction HO + H2O → H2O + OH and its various isotopologues are computed using both tunneling-corrected transition state and quasi-classical trajectory methods on a recently developed global potential energy surface. On the one hand, the calculated rate coefficients and kinetic isotope effects agree well with available experimental results, indicating the high fidelity of the potential energy surface. On the other hand, the observed normal primary and inverse secondary kinetic isotope effects appear to be prevalent in hydrogen abstraction reactions, which are rationalized by the change of classical and adiabatic minimum energy paths. In addition, there exists strong non-Arrhenius behavior at low temperatures due to the significant quantum tunneling effect. [ABSTRACT FROM AUTHOR]

Artificial photosynthetic production of hydrogen peroxide (H2O2) using conjugated organic polymer semiconductor photocatalysts is a promising approach. However, its application is limited mainly by the rapid rate of photogenerated carrier complexation. Here, we have prepared three novel porphyrin-based donor–acceptor conjugated organic polymers using porphyrin as a precursor and benzene–diamine ligands as basic blocks for the photocatalytic and efficient production of H2O2 under pure water. Density functional theory (DFT) calculations show that aniline ligands act as electron donors (D) and porphyrins act as electron acceptors (A). The TCFPP-TPD exhibits efficient photocatalytic H2O2 production with an initial rate of 1180 μmol g−1 h−1 under visible light (λ > 420 nm) irradiation without any additional sacrificial agents or co-catalysts. By increasing the number of benzene rings, the electron-donating ability of the benzene–diamine ligands was significantly enhanced, improving their electron-donor–acceptor (D–A) interactions with the porphyrins and facilitating the separation of the photogenerated electron–hole pairs. Moreover, the possible process for producing H2O2 through TCFPP-TPD photocatalysis was disclosed through in situ FT-IR and electron spin resonance (ESR). This study proposes novel design concepts for the rational construction of D–A structures with the aim of increasing the charge separation efficiency, which is crucial for the effective production of H2O2. [ABSTRACT FROM AUTHOR]

The co‐assembly naphthalimide/perylene diimide (NDINH/PDINH) supramolecular photocatalysts were successfully synthesized via a rapid solution dispersion method. A giant internal electric field (IEF) in co‐assembly structure was built by the larger local dipole. NDINH coated on PDINH could reduce the reflected electric field over PDINH to improve its responsive activity to ultraviolet light. Resultantly, an efficient full‐spectrum photocatalytic overall water splitting activity with H2 and O2 evolution rate of 317.2 and 154.8 μmol g−1 h−1 for NDINH/PDINH together with optimized O2 evolution rate with 2.61 mmol g−1 h−1 using AgNO3 as a sacrificial reagent were achieved. Meanwhile, its solar‐to‐hydrogen efficiency was enhanced to 0.13 %. The enhanced photocatalytic activity was primarily attributed to the IEF between NDINH and PDINH, significantly accelerating transfer and separation of photogenerated carriers. Additionally, a direct Z‐Scheme pathway of carriers contributed to a high redox potential. The strategy provided a new perspective for the design of supramolecular photocatalysts. [ABSTRACT FROM AUTHOR]

The co‐assembly naphthalimide/perylene diimide (NDINH/PDINH) supramolecular photocatalysts were successfully synthesized via a rapid solution dispersion method. A giant internal electric field (IEF) in co‐assembly structure was built by the larger local dipole. NDINH coated on PDINH could reduce the reflected electric field over PDINH to improve its responsive activity to ultraviolet light. Resultantly, an efficient full‐spectrum photocatalytic overall water splitting activity with H2 and O2 evolution rate of 317.2 and 154.8 μmol g−1 h−1 for NDINH/PDINH together with optimized O2 evolution rate with 2.61 mmol g−1 h−1 using AgNO3 as a sacrificial reagent were achieved. Meanwhile, its solar‐to‐hydrogen efficiency was enhanced to 0.13 %. The enhanced photocatalytic activity was primarily attributed to the IEF between NDINH and PDINH, significantly accelerating transfer and separation of photogenerated carriers. Additionally, a direct Z‐Scheme pathway of carriers contributed to a high redox potential. The strategy provided a new perspective for the design of supramolecular photocatalysts. [ABSTRACT FROM AUTHOR]

Development of highly efficient and metal‐free photocatalysts for bacterial inactivation under natural light is a major challenge in photocatalytic antibiosis. Herein, we developed an acidizing solvent‐thermal approach for inserting a non‐conjugated ethylenediamine segment into the conjugated planes of 3,4,9,10‐perylene tetracarboxylic anhydride to generate a photocatalyst containing segregated π‐conjugation units (EDA‐PTCDA). Under natural light, EDA‐PTCDA achieved 99.9 % inactivation of Escherichia coli and Staphylococcus aureus (60 and 45 min), which is the highest efficiency among all the natural light antibacterial reports. The difference in the surface potential and excited charge density corroborated the possibility of a built‐in electron‐trap effect of the non‐conjugated segments of EDA‐PTCDA, thus forming a highly active EDA‐PTDA/bacteria interface. In addition, EDA‐PTCDA exhibited negligible toxicity and damage to normal tissue cells. This catalyst provides a new opportunity for photocatalytic antibiosis under natural light conditions. [ABSTRACT FROM AUTHOR]

Development of highly efficient and metal‐free photocatalysts for bacterial inactivation under natural light is a major challenge in photocatalytic antibiosis. Herein, we developed an acidizing solvent‐thermal approach for inserting a non‐conjugated ethylenediamine segment into the conjugated planes of 3,4,9,10‐perylene tetracarboxylic anhydride to generate a photocatalyst containing segregated π‐conjugation units (EDA‐PTCDA). Under natural light, EDA‐PTCDA achieved 99.9 % inactivation of Escherichia coli and Staphylococcus aureus (60 and 45 min), which is the highest efficiency among all the natural light antibacterial reports. The difference in the surface potential and excited charge density corroborated the possibility of a built‐in electron‐trap effect of the non‐conjugated segments of EDA‐PTCDA, thus forming a highly active EDA‐PTDA/bacteria interface. In addition, EDA‐PTCDA exhibited negligible toxicity and damage to normal tissue cells. This catalyst provides a new opportunity for photocatalytic antibiosis under natural light conditions. [ABSTRACT FROM AUTHOR]

Despite the intriguing potential shown by Sn‐based perovskite oxides in CO2 electroreduction (CO2RR), the rational optimization of their CO2RR properties is still lacking. Here we report an effective strategy to promote CO2‐to‐HCOOH conversion of Sn‐based perovskite oxides by A‐site‐radius‐controlled Sn−O bond lengths. For the proof‐of‐concept examples of Ba1−xSrxSnO3, as the A‐site cation average radii decrease from 1.61 to 1.44 Å, their Sn−O bonds are precisely shortened from 2.06 to 2.02 Å. Our CO2RR measurements show that the activity and selectivity of these samples for HCOOH production exhibit volcano‐type trends with the Sn−O bond lengths. Among these samples, the Ba0.5Sr0.5SnO3 features the optimal activity (753.6 mA ⋅ cm−2) and selectivity (90.9 %) for HCOOH, better than those of the reported Sn‐based oxides. Such optimized CO2RR properties could be attributed to favorable merits conferred by the precisely controlled Sn−O bond lengths, e.g., the regulated band center, modulated adsorption/activation of intermediates, and reduced energy barrier for *OCHO formation. This work brings a new avenue for rational design of advanced Sn‐based perovskite oxides toward CO2RR. [ABSTRACT FROM AUTHOR]

Despite the intriguing potential shown by Sn‐based perovskite oxides in CO2 electroreduction (CO2RR), the rational optimization of their CO2RR properties is still lacking. Here we report an effective strategy to promote CO2‐to‐HCOOH conversion of Sn‐based perovskite oxides by A‐site‐radius‐controlled Sn−O bond lengths. For the proof‐of‐concept examples of Ba1−xSrxSnO3, as the A‐site cation average radii decrease from 1.61 to 1.44 Å, their Sn−O bonds are precisely shortened from 2.06 to 2.02 Å. Our CO2RR measurements show that the activity and selectivity of these samples for HCOOH production exhibit volcano‐type trends with the Sn−O bond lengths. Among these samples, the Ba0.5Sr0.5SnO3 features the optimal activity (753.6 mA ⋅ cm−2) and selectivity (90.9 %) for HCOOH, better than those of the reported Sn‐based oxides. Such optimized CO2RR properties could be attributed to favorable merits conferred by the precisely controlled Sn−O bond lengths, e.g., the regulated band center, modulated adsorption/activation of intermediates, and reduced energy barrier for *OCHO formation. This work brings a new avenue for rational design of advanced Sn‐based perovskite oxides toward CO2RR. [ABSTRACT FROM AUTHOR]

[Display omitted] • CoFe oxide/perylene diimide Z-scheme heterojunction was constructed. • Z-scheme heterojunction owns superior redox ability for high H 2 O 2 production. • The destruction of CIP structure is verified by HPLC chromatograms. • Antibiotic toxicity removal under photocatalysis-self-Fenton system. Fenton technology has been famous on antibiotics removal, but seriously restricted by the extra addition of H 2 O 2 and low mineralization efficiency. Herein, we develop a novel cobalt-iron oxide/perylene diimide organic supermolecule (CoFeO/PDIsm) Z-scheme heterojunction under photocatalysis-self-Fenton system, in which the holes (h+) of photocatalyst can mineralize organic pollutants and the photo-generated electrons (e−) are used to in-situ H 2 O 2 production with high efficiency. The CoFeO/PDIsm exhibits superior in-situ H 2 O 2 production at a rate of 281.7 µmol g−1 h−1 in contaminating solution, correspondingly of total organic carbon (TOC) removal rate of ciprofloxacin (CIP) is 63.7 %, far exceeding current photocatalysts. The high H 2 O 2 production rate and remarkable mineralization ability are ascribed to great charge separation in Z-scheme heterojunction. This work provides a novel Z-scheme heterojunction with photocatalysis-self-Fenton system for environmental-friendly removing the organic containment. [ABSTRACT FROM AUTHOR]

Rationally constructing atom‐precise active sites is highly important to promote their catalytic performance but still challenging. Herein, this work designs and constructs ZSM‐5 supported Cu and Ag dual single atoms as a proof‐of‐concept catalyst (Ag1−Cu1/ZSM‐5 hetero‐SAC (single‐atom catalyst)) to boost direct oxidation of methane (DOM) by H2O2. The Ag1−Cu1/ZSM‐5 hetero‐SAC synthesized via a modified co‐adsorption strategy yields a methanol productivity of 20,115 µmol gcat−1 with 81% selectivity at 70 °C within 30 min, which surpasses most of the state‐of‐the‐art noble metal catalysts. The characterization results prove that the synergistic interaction between silver and copper facilitates the formation of highly reactive surface hydroxyl species to activate the C−H bond as well as the activity, selectivity, and stability of DOM compared with SACs, which is the key to the enhanced catalytic performance. This work believes the atomic‐level design strategy on dual‐single‐atom active sites should pave the way to designing advanced catalysts for methane conversion. [ABSTRACT FROM AUTHOR]

Although the internal electric field (IEF) of bismuth oxyiodide (BiOI) is acknowledged as a potent driving force for efficient charge separation, enhancing the intensity of IEF remains a challenge. Herein, highly crystalline BiOI nanosheets with I‐rich surface are employed to intensify IEF and direct the charge migration. In comparison to I‐poor BiOI nanosheets, which possess Bi−O layer termination and I‐defects, the I‐rich BiOI demonstrates 62.5‐fold improvement in IEF intensity to its well‐developed high crystalline structure, and its IEF direction is reversed by the surface I‐rich layers. This intensified IEF of I‐rich BiOI induces numerous holes (h+) to migrate to the surface of primary exposed (001) facets and electrons (e−) to the lateral facets efficiently, resulting in efficient charge separation spatially. Additionally, the surface accumulates h+ and superoxide radicals and acts in synergy to enhance the photodegradation of phenol. The photocatalytic activity of the I‐rich BiOI is found to be approximately fivefold and threefold higher than that of I‐poor BiOI under full spectra and visible light, respectively. Herein, the manipulation of IEF through surface and bulk structure regulation of BiOI for efficient charge separation is discussed, expecting to rationally improve photocatalytic performances. [ABSTRACT FROM AUTHOR]

The development of conjugated polymers especially n‐type polymer semiconductors is powered by the design and synthesis of electron‐deficient building blocks. Herein, a strong acceptor building block with di‐metallaaromatic structure was designed and synthesized by connecting two electron‐deficient metallaaromatic units through a π‐conjugated bridge. Then, a double‐monomer polymerization methodology was developed for inserting it into conjugated polymer scaffolds to yield metallopolymers. The isolated well‐defined model oligomers indicated polymer structures. Kinetic studies based on nuclear magnetic resonance and ultraviolet–visible spectroscopies shed light on the polymerization process. Interestingly, the resulted metallopolymers with dπ–pπ conjugations are very promising electron transport layer materials which can boost photovoltaic performance of an organic solar cell, with power conversion efficiency up to 18.28 % based on the PM6 : EH‐HD‐4F non‐fullerene system. This work not only provides a facile route to construct metallaaromatic conjugated polymers with various functional groups, but also discovers their potential applications for the first time. [ABSTRACT FROM AUTHOR]

The development of conjugated polymers especially n‐type polymer semiconductors is powered by the design and synthesis of electron‐deficient building blocks. Herein, a strong acceptor building block with di‐metallaaromatic structure was designed and synthesized by connecting two electron‐deficient metallaaromatic units through a π‐conjugated bridge. Then, a double‐monomer polymerization methodology was developed for inserting it into conjugated polymer scaffolds to yield metallopolymers. The isolated well‐defined model oligomers indicated polymer structures. Kinetic studies based on nuclear magnetic resonance and ultraviolet–visible spectroscopies shed light on the polymerization process. Interestingly, the resulted metallopolymers with dπ–pπ conjugations are very promising electron transport layer materials which can boost photovoltaic performance of an organic solar cell, with power conversion efficiency up to 18.28 % based on the PM6 : EH‐HD‐4F non‐fullerene system. This work not only provides a facile route to construct metallaaromatic conjugated polymers with various functional groups, but also discovers their potential applications for the first time. [ABSTRACT FROM AUTHOR]

Carrier transport is an equally decisive factor as carrier separation for elevating photocatalytic efficiency. However, limited by indefinite structures and low crystallinities, studies on enhancing carrier transport of organic photocatalysts are still in their infancy. Here, we develop an σ‐linkage length modulation strategy to enhance carrier transport in imidazole‐alkyl‐perylene diimide (IMZ‐alkyl‐PDI, corresponding to D‐σ‐A) photocatalysts by controlling π–π stacking distance. Ethyl‐linkage can shorten π–π stacking distance (3.19 Å) the most among IMZ‐alkyl‐PDIs (where alkyl=none, ethyl, and n‐propyl) via minimizing steric hindrance between D and A moieties, which leads to the fastest carrier transport rates. Thereby, IMZ‐ethyl‐PDI exhibits remarkable enhancement in phenol degradation with 32‐fold higher rates than IMZ‐PDI, as well as the oxygen evolution rate (271‐fold increased). In microchannel reactors, IMZ‐ethyl‐PDI also presents 81.5 % phenol removal with high‐flux surface hydraulic loading (44.73 L m−2 h−1). Our findings provide a promising molecular design guideline for high‐performance photocatalysts and elucidate crucial internal carrier transport mechanisms. [ABSTRACT FROM AUTHOR]

Carrier transport is an equally decisive factor as carrier separation for elevating photocatalytic efficiency. However, limited by indefinite structures and low crystallinities, studies on enhancing carrier transport of organic photocatalysts are still in their infancy. Here, we develop an σ‐linkage length modulation strategy to enhance carrier transport in imidazole‐alkyl‐perylene diimide (IMZ‐alkyl‐PDI, corresponding to D‐σ‐A) photocatalysts by controlling π–π stacking distance. Ethyl‐linkage can shorten π–π stacking distance (3.19 Å) the most among IMZ‐alkyl‐PDIs (where alkyl=none, ethyl, and n‐propyl) via minimizing steric hindrance between D and A moieties, which leads to the fastest carrier transport rates. Thereby, IMZ‐ethyl‐PDI exhibits remarkable enhancement in phenol degradation with 32‐fold higher rates than IMZ‐PDI, as well as the oxygen evolution rate (271‐fold increased). In microchannel reactors, IMZ‐ethyl‐PDI also presents 81.5 % phenol removal with high‐flux surface hydraulic loading (44.73 L m−2 h−1). Our findings provide a promising molecular design guideline for high‐performance photocatalysts and elucidate crucial internal carrier transport mechanisms. [ABSTRACT FROM AUTHOR]