Transfer Of Photogenerated Electrons Research Articles

Biotemplated Fe/La-co-doped TiO2 for photocatalytic depth treatment of compressed leachate from refuse transfer station.

Compressed leachate is a contaminated liquid containing various organic and inorganic pollutants produced in municipal refuse transfer stations, which pollute soil and groundwater, posing serious risks to the environment and human health. The Environmental Technology Co., Ltd. (Shenzhen, Guangdong Province, South China) treated compressed leachate obtained from a refuse transfer station. The chemical oxygen demand (COD) (641.2mg/L) of treated compressed leachate did not meet the wastewater quality standards in China for discharge into municipal sewers (COD ≤ 500mg/L) and the company's design discharge requirements (COD ≤ 400mg/L). Therefore, their further in-depth treatment is necessary. To this end, waste tobacco leaves were used as the biotemplate herein, and Fe/La-co-doped TiO2 (xFe,yLa)-TTiO2(g) was synthesized using a solvothermal-assisted biotemplating method. The photocatalytic depth treatment of compressed leachate was performed under simulated solar light using the prepared catalysts. After (3Fe,3La)-TTiO2(g) treatment, the COD of the leachate decreased from 641.2 to 280.1mg/L, and the COD removal rate was 1.2, 1.1, and 1.6 times higher than that of pure Fe-doped, La-doped and non-biological template TiO2, respectively. Characterization confirmed that the biological template endowed the catalyst with a unique morphology and high specific surface area. Its rich activity sites are conducive to enhancing the adsorption capacity of pollutants and providing an ideal place for photocatalytic reactions. Co-doping with iron and lanthanum ions altered the band structure of TiO2 and promoted the interconversion of Fe3+/Fe2+ and La3+/La2+ during photocatalysis. First-principles density functional theory simulations demonstrated that co-doping Fe and La in TiO2 created impurity levels that facilitated the transfer of photogenerated electrons. This study provides a new purification pathway for the depth treatment of compressed leachate.

Preparation of nanosheet g-C3N4 coupled with Polycalix [4] resorcinarene: Survey characterization and photocatalytic activity for the degradation of 4-Nitrophenol

Here, we have synthesized Polycalix[4]resorcinarene (PC4RA) covalently coupled with carbon-modified porous graphitic carbon nitride (g-C3N4). The nanocomposites were characterized by (FTIR), (XRD), (SEM), Transmission (TEM), and DRS–UV–Vis spectroscopic methods. Photocatalytic activities of the PC4RA/g-C3N4 nanocomposites with different ratios of g-C3N4 were evaluated for degradation of 4-Nitrophenol under visible light irradiation under light irradiation of λ ≥ 320 nm. Three parameters were applied including the initial concentration of 4-nitrophenol, the amount of photocatalyst, and irradiation time. and the results of the photocatalytic performance suggest that the catalytic activity is strongly influenced by the presence of the g-C3N4 content. Especially the nanocomposite’s photocatalytic efficiency was the highest (98.32 % after 120 min) when the ratio of g-C3N4 was (1/2). However, an increase of the photocatalytic activities was related to the interfacial transfer of photogenerated electrons and holes, leading to the effective charge separation. The durability and stability of the nanocomposites have been examined and can endure the experimental conditions even after eight successive cycles. This approach opens up an avenue for the fabrication of graphitic carbon nitrite-based metal-free heterogeneous nanocomposites with high catalytic performance.

Embedding ZnCo2O4 quantum dots onto graphdiyne (g-CnH2n-2) nanosheets as a 0D/2D S-scheme heterojunction for highly efficient photocatalytic H2 evolution

The design of environmentally friendly and cost-effective S-scheme heterojunctions with robust interfacial interactions is pivotal for enhancing photocatalytic performance and facilitating practical application. In this work, ZnCo2O4 quantum dots (QDs)/graphdiyne (ZCOG) S-scheme heterojunction was synthesized by a simple hydrothermal method. ZnCo2O4 QDs with quantum size effect were prepared by calcination, while graphdiyne (GDY) nanosheets were synthesized by reduction-elimination reaction using CuBr as catalyst. The maximum hydrogen production rate of ZCOG reaches 2472.80 μmol g-1h−1, which is 30.75 and 10.84 times higher than that of ZnCo2O4 QDs and GDY, respectively. This significantly enhanced photocatalytic activity is attributed to the strongly coupled S-scheme heterojunction between GDY and ZnCo2O4 QDs, which accelerates the photogenerated electron transfer while effectively suppressing the recombination of photogenerated carriers. In addition, the quantum size effect of the ZnCo2O4 QDs leads to an increase in the width of the electronic forbidden band, which enhances the energy of electrons (holes) in the conduction band (valence band). The S-scheme mechanism of ZCOG was revealed by in situ XPS, UPS and TRPL spectroscopy, and the reliability of the conclusions was further verified by DFT calculations. This work provides an efficient strategy for the construction of GDY-based photocatalysts with quantum size effect.

CdS/Bi2S3/NiS ternary heterostructure-based photoelectrochemical immunosensor for the sensitive detection of carbohydrate antigen 125

The sensitive, accurate and rapid detection of carbohydrate antigen 125 (CA125) is essential for the early diagnosis and clinical management of ovarian cancer, but there is still challenge. Herein, a photoelectrochemical (PEC) immunosensor based on CdS/Bi2S3/NiS ternary sulfide heterostructured photocatalyst was presented for the detection of CA125. The CdS/Bi2S3/NiS was synthesized by a one-step hydrothermal approach. The heterojunction comprising of CdS and Bi2S3 could separate photogenerated carriers, the introduced narrow bandgap NiS could act as electron-conducting bridge to facilitate the transfer of interfacial photogenerated electrons, thereby improving the photoelectric conversion efficiency. Due to their synergistic effect, the photocurrent response produced by the composite was up to 14.6 times of pure CdS. On the basis, a PEC immunosensor was constructed by introducing the CA125 antibody through thioglycolic acid linkage. It was found that the resulting immunosensor showed good performance. Under the optimized conditions, its linear detection range was as wide as 1 pg mL−1−50 ng mL−1, and the detection limit was low to 0.85 pg mL−1. Furthermore, we experimentally tested its anti-interference, stability and reproducibility, and satisfactory results were achieved. The practicable feasibility of the sensor was confirmed by testing serum sample. Thus this work provided a simple, fast and enough sensitive approach for CA125 monitoring.

Study on the performance of photothermal catalyzed carbon dioxide hydrogenation to CH4 over doped sodium tantalate-based perovskite catalysts

NaTaO3 (ABO3)-based catalysts with B-site substituted metals M= (Co, Ni, Fe, Ga, Ti) for photothermal-catalyzed carbon dioxide reduction hydrogenation to C1 products were prepared via a simple one-step hydrothermal method. The B-site metal doping catalysts exhibited excellent performance for the aimed photothermal catalytic reaction. Among them, the NaTa0.9Co0.1O3 was the most eye-catching catalyst with a stable crystal cell, an excellent heterojunction structure, and a bandgap structure for light absorption, The fine structure properties results in a low electron-hole recombination rate and high photoelectron transfer efficiency under light conditions. The suitable alkaline adsorption sites and thermal reduction properties also be the effective assistance for the catalytic process. The CO yield and CH4 yield of the NaTa0.9Co0.1O3 catalyst were 6.6 times and 120 times higher than those of the pure-phase NaTaO3, respectively, and the CH4 selectivity was up to 98% under the illumination condition of 300 ℃. For the photothermal hydrogenation reaction, thermal catalysis dominates the reaction, and light illumination promotes the generation and transfer of photogenerated electrons and improves the catalyst stability. The above studies show that NaTaO3 based perovskite has a great potential in the field of photothermal catalyzed carbon dioxide reduction.

Revealing the Enhanced Visible-light-driven Photocatalytic Activity of In2S3/CeO2 Heterojunction: Bandgap Structure Analysis and Active Radicals Determination

Background: The widespread presence of persistent organic pollutants, such as dyes in effluent from printing and textile industries, poses a significant threat to aquatic life and human health. Photocatalytic degradation is widely recognized as a promising technology to address this pollution crisis. The efficiency of photocatalysis is intricately tied to both the active radicals and the band structure of the catalyst. These factors play a crucial role in governing the photodegradation of dye molecules. Methods: In2S3/CeO2 heterojunctions were synthesized using an in-situ precipitation method and subsequently analyzed through SEM, XRD, and XPS techniques. Notably, the bandgap structure of the heterojunctions was examined through UV-Vis DRS. The photocatalytic performance of the synthesized samples was assessed by studying the degradation of methyl orange. To further validate the photocatalytic process, EPR spectroscopy was employed to confirm the presence of radicals generated within the heterojunction. Results: The heterojunction displayed a characteristic type-II structure, enhancing light absorption and facilitating the separation of photoinduced carriers. Among the In2S3/CeO2 composites, the one with a 15 wt% CeO2 content exhibited the highest photocatalytic activity, achieving an 88% degradation of methyl orange after 90 min of exposure to visible light irradiation. Additionally, •O2 − is identified as the primary active species responsible for degradation. Conclusion: UV-Vis DRS illustrated the improved transfer and separation of photogenerated electrons attributed to the optimized band structure of the heterojunction. EPR spectroscopy yielded valuable information on active radicals, thereby proposing the photocatalytic degradation mechanism.

Measurement of interfacial charge transfer rate during visible light CO2 reduction under bias voltage conditions

The study of photogenerated electron transfer pathway and time scale in photoelectrocatalysis is the key factor to improve the efficiency of light energy utilization. At present, the reduction of CO2 by visible light is one of the hotspots of research, but it is difficult to determine the reduction reaction and mechanism. Therefore, we use electrochemical in situ growth technology to prepare Bi2(MoO4)3, and then use photoelectrocatalytic method to reduce CO2. The results show that the rate of charge transfer at the interface is about 10−18 cm4/s in the reduction of CO2 by visible light under bias voltage, and the catalyst can react stably for 10 h. This provides a way to optimize the photogenerated electron transfer model and to design the catalysts for the reduction of carbon dioxide under visible light.

Highly Conjugated Nanozyme with Non Coordination Saturation for Cascaded Enhanced POD Reaction Driving Antibacterial Therapy

AbstractThe misuse of antibiotics leads to emergence of drug‐resistant bacteria. Developing artificial nanozymes with high stability and excellent catalytic performance is desirable to substitute for antibiotics, but still remains huge challenge. Herein, the study reports a new strategy for cascaded enhanced peroxidase (POD) reaction driving antibacterial therapy via constructing 2D conjugated metal‐organic frameworks (MOFs) with non coordination saturation as nanozyme. It is demonstrated that the non coordination saturation Cu atom promotes the adsorption of H2O2, followed by the Cu‐HHTP MOFs with high conjugated structure can enhance the photogenerated electron transfer for ·OH generation in POD reaction. The sequential enhancement of substrate adsorption and decomposition endows the as‐made Cu‐HHTP MOFs with outstanding antibacterial property of >99.9999% elimination with a concentration only 1/133 that of traditional nanozyme. In addition, the study also certifies its excellent in vivo antimicrobial activity and biocompatibility, indicating the therapeutic potential for infections by drug‐resistant bacteria.

Interface Regulation of Bi3TiNbO9/Rh Photocatalysts by Introducing Ultrathin Heterolayer to Enhance Overall Water Splitting

AbstractAurivillius compounds‐based photocatalysts have attracted extensive interest largely due to their ferroelectric properties and modifiable characteristics arising from the alternate stacking of structural units. However, the interfacial Schottky barrier between such semiconducting compounds as light absorbers and metallic cocatalysts for hydrogen evolution restrains the transfer of photogenerated electrons, resulting in low photocatalytic overall water splitting activity and stability. Here, an anions‐induced surface structure transformation strategy is employed to modulate the interface structure between Bi3TiNbO9 as a typical Aurivillius compound and the cocatalyst Rh by in situ growing ultrathin Bi2MoO6 heterolayer on the surface of Bi3TiNbO9 nanosheets. The introduction of Bi2MoO6 heterolayer lowers the energy barrier near the Bi3TiNbO9 surface, which can facilitate the transfer of the photogenerated electrons from bulk to surface and thus the reduction of Rh cocatalyst for highly active hydrogen production. Compared with the Bi3TiNbO9‐Rh photocatalyst, the proportion of low‐valence metallic Rh0 in Bi2MoO6 heterolayer‐modified Bi3TiNbO9‐Rh (Bi3TiNbO9‐Bi2MoO6‐Rh) is improved by 7.76%, giving rise to a photocatalytic overall water splitting activity enhancement by a factor of 4.74. This strategy emphasizes the importance of interface regulation in promoting the transfer of photogenerated charge carriers in Aurivillius‐type photocatalysts, providing an effective pathway for designing and fabricating high‐performance photocatalysts.

Photoreduction of CO2 on Pd-In2O3: Synergistic optimization of progressive electron transfer via amorphous/crystalline Pd and oxygen vacancies

The progressive transfer of photogenerated electrons between the catalyst components and reactants is of great significance for photocatalysis. Amorphous Pd (PdA) and oxygen vacancies (VOs) were simultaneously introduced in Pd-In2O3 exploiting hydrogen-induced amorphization effects; 0.6 wt% Pd-In2O3 exhibited a 4.5-fold increase in activity and a 3.2-fold higher selectivity toward CH3OH + CO (63.62 %) compared with In2O3. Multiple in situ techniques and theoretical calculations revealed that intercomponent electron transfer channels were established via various interface structures formed between PdA or crystalline Pd (PdC) and In2O3; PdA acted as electronic pump, facilitating the transfer and separation of photogenerated electrons, resulting in their subsequent enrichment on the surface of PdA. Simultaneously, PdA acted as electron-donating adsorption site for H2O, increasing the number of electrons received by H2O, further inhibiting the competitive adsorption of H2O and CO2 on VO sites, and promoting the hydrogen evolution reaction. Additionally, the electronic coupling between PdC and VOs could significantly decrease the electron-donating ability of VOs, reducing the number of electrons received by CO2, thus effectively regulating the degree of CO2 reduction. This study employs PdA/PdC and VOs to synergistic optimize the progressive transfer of photogenerated electrons, and presents a novel approach for elucidating the catalytic mechanism.

0D/2D dual Fenton α-Fe2O3/Fe-doped g-C3N4 photocatalyst and the synergistic photo-Fenton catalytic mechanism insight

A novel dual Photo-Fenton photocatalyst Fe2O3–Fe–CN with excellent Fe(III)/Fe(II) conversion efficiency and trace metal ion leaching rate has been fabricated by in-situ deposition of α-Fe2O3 quantum dots on ultrathin porous Fe-doped carbon nitride (Fe–CN) nanosheets. The iron species in Fe–CN and α-Fe2O3 QDs constitute a mutually reinforcing dual Photo-Fenton effect. The 4% Fe2O3–Fe–CN showed superior performance with kobs values 8.60 and 4.80 folders greater than pure CN and Fe–CN, respectively. The synergistic effect between α-Fe2O3 QDs and the ultrathin porous structure of Fe–CN is the primary reason for the outstanding catalytic performance exhibited by α-Fe2O3/Fe–CN. On one hand, the ultrathin porous structure of Fe–CN promotes the rapid transfer of photogenerated electrons. On the other hand, the efficient photogenerated charge separation at the α-Fe2O3/Fe–CN interface enables more photogenerated electrons to participate in the Fe3+/Fe2+ conversion and H2O2 activation. The trapping experiments demonstrate that •OH and •O2− are the primary active species in TC degradation. This work presents novel insights into the design of efficient heterogeneous Fenton catalysts for practical applications.

Facile preparation of ZIF-67 on TiO2 and enhancement photocathodic protection for 316L stainless steel

Photocathodic protection (PCP) anticorrosion using sunlight is a green and sustainable technology. However, the ease of carriers compounding and the low light utilization are still the main restraints to its development. To develop an effective photoanode, a metal-organic framework (MOF, i.e., ZIF-67) material is electrodeposited and grown in-situ on TiO2 nanorods. The morphological structure, light absorption properties, photoelectrochemical properties and cathodic protection principle of ZIF-67/TiO2 photoanode are analysed by SEM, PL, I-V and EIS. The material characterization and light absorption characteristics show that the photoanode has good light absorption performance and higher electron hole separation efficiency. Photoelectrochemical test shows that ZIF-67/TiO2 photoanode has excellent photocathodic protection for 316L stainless steel (316L SS). ZTRs-60 has the optimal protection effect. Under simulated sunlight, the OCP of 316L SS coupled ZTRs-60 is -0.41 V vs. Ag/AgCl, and the current density of the I-t curve can reach 20 μA/cm2. EIS and Tafel tests show that the photogenerated electrons transfer to the stainless steel surface, which promotes the cathode polarization process and alleviates the metal corrosion.

Synthesis of Zn0.2Cd0.8S/MoS2/rGO photocatalyst for efficient solar-driven selective organic conversion

ZnxCd(1-x)S solid solution was constructed by introducing zinc ions in the process of hydrothermal synthesis of CdS. To further improve the catalyst activity, Zn0.2Cd0.8S was combined with graphene and MoS2, and then the Zn0.2Cd0.8S/MoS2/rGO ternary composites were obtained. Its photocatalytic reactivity was evaluated by the catalytic oxidative coupling of benzylamine and the photocatalytic semi-dehydrogenation of 1,2,3,4-tetrahydroisoquinoline (THIQ). When Zn0.2Cd0.8S/MoS2/rGO was used in photocatalytic benzylamine oxidative coupling reaction, the conversion reached 95 % after 7 h and the selectivity of N-benzyl-1-phenylmethylimide (BPMI) was 99 %. It was further applied to the photocatalytic semi-dehydrogenation of THIQ, the conversion reached 96 % after 7 h reaction in O2 atmosphere, and the selectivity of 3,4-dihydroisoquinoline (DHIQ) reached 99 %. The heterojunction between Zn0.2Cd0.8S and MoS2 can effectively reduce the recombination efficiency of carrier. The introduction of graphene can increase the active site and promote the transfer of photogenerated electrons. The synergistic effect of MoS2 and graphene makes Zn0.2Cd0.8S have outstanding photocatalytic performance. Cycling experiments show that the ternary composite photocatalyst of Zn0.2Cd0.8S/MoS2/rGO have high stability and recyclability. The possible reaction mechanism of photocatalytic oxidative coupling of benzylamine and semi-dehydrogenation of THIQ was proposed by theoretical calculations and the active species capturing experiments.

A Self-Assembled MOF-Escherichia Coli Hybrid System for Light-Driven Fuels and Valuable Chemicals Synthesis.

The development of semi-artificial photosynthetic systems, which integrate metal-organic frameworks (MOFs) with industrial microbial cell factories for light-driven synthesis of fuels and valuable chemicals, represents a highly promising avenue for both research advancements and practical applications. In this study, an MOF (PCN-222) utilizing racemic-(4-carboxyphenyl) porphyrin and zirconium chloride (ZrCl4) as primary constituents is synthesized. Employing a self-assembly process, a hybrid system is constructed, integrating engineered Escherichia coli (E. coli) to investigate light-driven hydrogen and lysine production. These results demonstrate that the light-irradiated biohybrid system efficiently produce H2 with a quantum efficiency of 0.75% under full spectrum illumination, the elevated intracellular reducing power NADPH is also observed. By optimizing the conditions, the biohybrid system achieves a maximum lysine production of 18.25mg L-1, surpassing that of pure bacteria by 332%. Further investigations into interfacial electron transfer mechanisms reveals that PCN-222 efficiently captures light and facilitates the transfer of photo-generated electrons into E. coli cells. It is proposed that the interfacial energy transfer process is mediated by riboflavin, with facilitation by secreted small organic acids acting as hole scavengers for PCN-222. This study establishes a crucial foundation for future research into the light-driven biomanufacturing using E. coli-based hybrid systems.

Enhanced efficiency of AgAlO2/g-C3N4 binary composite to degrade organic pollutants for environmental remediation under visible light irradiation

This study explores the utilization of semiconductor-based photocatalysts for environmental remediation through photocatalytic degradation, harnessing solar energy for effective treatment. The primary focus is on the application of photocatalytic technology for the degradation of 2-chlorophenol and methylene blue, critical pollutants requiring remediation. The research involves the synthesis of binary AgAlO2/g-C3N4 nanocomposites through an exchange ion method, subsequent calcination, and sonication. This process enhances the transfer of photogenerated electrons from AgAlO2 to g-C3N4, resulting in a significantly increased reductive electron charge on the surface of g-C3N4. The photocatalytic activity of the synthesized composites is comprehensively examined in the degradation of 2-chlorophenol and methylene blue through detailed crystallographic, electron-microscopy, photoemission spectroscopy, electrochemical, and spectroscopic characterizations. Among the various composites, AgAlO2/20% g-C3N4 emerges as the most active photocatalyst, achieving an impressive 98% degradation of methylene blue and 97% degradation of 2-chlorophenol under visible light. Notably, AgAlO2/20% g-C3N4 surpasses bare AgAlO2 and bare g-C3N4, exhibiting 1.66 times greater methylene blue degradation and constant rate (k) values of 20.17 × 10−3 min−1, 4.18 × 10−3 min−1 and 3.48 × 10−3 min−1, respectively. The heightened photocatalytic activity is attributed to the diminished recombination rate of electron-hole pairs. Scavenging evaluations confirm that O2•− and h+ are the primary photoactive species steering methylene blue photodegradation over AgAlO2/g-C3N4 in the visible region. These findings present new possibilities for the development of efficient binary photocatalysts for environmental remediation.

Photoactive cationic conjugated microporous polymers containing pyrimidine with an ‘adsorption-kill’ antibacterial strategy for infected wound healing

Pathogenic bacterial invasion leads to severe inflammation that hinders wound healing, and it has become a major medical threat worldwide. Photodynamic therapy (PDT) has emerged as a promising strategy for treating microbial infection; however, developing a dressing with PDT effect and excellent biological functions poses a formidable challenge. Herein, a novel cationic pyrimidine-modified conjugated microporous polymer, BPyMe-CMP, was rationally designed and synthesized via a Sonogashira-Hagiwara and SN2 substitution reaction. The BPyMe-CMP exhibited weak interfacial charge transfer resistance and demonstrated superior photoinducible carrier separation, thereby displaying an excellent photoelectric response. Consequently, the BPyMe-CMP could readily generate reactive oxygen species under visible light irradiation to kill bacteria. In addition to enhancing the photogenerated electron transfer process, BPyMe-CMP also provided abundant attraction sites for bacteria to reinforce the antibacterial ability. The deposition of BPyMe-CMP onto polyvinyl alcohol-modified silk fibroin (SF/PVA) film served as a wound dressing to promote healing. The in vitro and in vivo experiments revealed that the SF/PVA@BPyMe-CMP induced M2-type macrophage polarization, promoted L929 fibroblast migration, exhibited bactericidal activity, and induced angiogenesis, which synergistically accelerated the healing of methicillin-resistant Staphylococcus aureus-infected wounds. This study provides data support to advance the construction of a multi-functional wound dressing based on pyrimidination and cationization for the treatment and rapid healing of infected wounds.

Ruthenium Single Atomic Sites Surrounding the Support Pit with Exceptional Photocatalytic Activity.

Single-metal atomic sites and vacancies can accelerate the transfer of photogenerated electrons and enhance photocatalytic performance in photocatalysis. In this study, a series of nickel hydroxide nanoboards (Ni(OH)x NBs) with different loadings of single-atomic Ru sites (w-SA-Ru/Ni(OH)x) were synthesized via a photoreduction strategy. In such catalysts, single-atomic Ru sites are anchored to the vacancies surrounding the pits. Notably, the SA-Ru/Ni(OH)x with 0.60 wt % Ru loading (0.60-SA-Ru/Ni(OH)x) exhibits the highest catalytic performance (27.6 mmol g-1 h-1) during the photocatalytic reduction of CO2 (CO2RR). Either superfluous (0.64 wt %, 18.9 mmol g-1 h-1; 3.35 wt %, 9.4 mmol-1 h-1) or scarce (0.06 wt %, 15.8 mmol g-1 h-1; 0.29 wt %, 21.95 mmol g-1 h-1; 0.58 wt %, 23.4 mmol g-1 h-1) of Ru sites have negative effect on its catalytic properties. Density functional theory (DFT) calculations combined with experimental results revealed that CO2 can be adsorbed in the pits; single-atomic Ru sites can help with the conversion of as-adsorbed CO2 and lower the energy of *COOH formation accelerating the reaction; the excessive single-atomic Ru sites occupy vacancies that retard the completion of CO2RR.

Ruthenium Single Atomic Sites Surrounding the Support Pit with Exceptional Photocatalytic Activity

AbstractSingle‐metal atomic sites and vacancies can accelerate the transfer of photogenerated electrons and enhance photocatalytic performance in photocatalysis. In this study, a series of nickel hydroxide nanoboards (Ni(OH)x NBs) with different loadings of single‐atomic Ru sites (w‐SA‐Ru/Ni(OH)x) were synthesized via a photoreduction strategy. In such catalysts, single‐atomic Ru sites are anchored to the vacancies surrounding the pits. Notably, the SA‐Ru/Ni(OH)x with 0.60 wt % Ru loading (0.60‐SA‐Ru/Ni(OH)x) exhibits the highest catalytic performance (27.6 mmol g−1 h−1) during the photocatalytic reduction of CO2 (CO2RR). Either superfluous (0.64 wt %, 18.9 mmol g−1 h−1; 3.35 wt %, 9.4 mmol−1 h−1) or scarce (0.06 wt %, 15.8 mmol g−1 h−1; 0.29 wt %, 21.95 mmol g−1 h−1; 0.58 wt %, 23.4 mmol g−1 h−1) of Ru sites have negative effect on its catalytic properties. Density functional theory (DFT) calculations combined with experimental results revealed that CO2 can be adsorbed in the pits; single‐atomic Ru sites can help with the conversion of as‐adsorbed CO2 and lower the energy of *COOH formation accelerating the reaction; the excessive single‐atomic Ru sites occupy vacancies that retard the completion of CO2RR.

Facile fabrication of carbon supported Bi2O3-BiOCl-Bi heterostructure to boost ammonia under visible light

In this paper, carbon supported Bi2O3-BiOCl-Bi heterostructures were successfully synthesized via a facile and simple hydrothermal method. A series of structure and morphology testing clearly showed that carbon and metallic Bi were deposited on the surface margin of Bi2O3-BiOCl, which benefited the rapid transfer of internal photogenerated electrons. Photophysical experiments including electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) indicated that the amount of surface oxygen vacancies (OVs) was significantly increased, which act as reactive active sites and therefore effectively enhance the photocatalytic performance. The photocatalytic N2 reduction yield of C@Bi2O3-BiOCl-Bi was remarkably improved to 400 μg·L−1, which was 3.63 times higher than that of BiOCl. This research demonstrated a feasible strategy to construct advanced photocatalyst by incorporating defect-rich structures and surface engineering.

Pd nanocubes/In2O3/hollow carbon microspheres with ultra-low interface resistance of Ohmic contact for efficient CO2 photoreduction

The utilization of CO2 photoreduction into valuable hydrocarbon fuels presents a promising avenue for mitigating climate change and providing a sustainable energy source. However, photogenerated carriers are highly prone to recombination, which adversely affects photocatalytic activity. In our study, we introduce a novel photocatalyst synthesis method, featuring an Ohmic contact (OC) structure that incorporates biomass-derived hollow carbon microspheres (HCM), Pd nanocubes (NC), and Indium Oxide (In2O3) through a simple yet effective thermal reduction method. This modification significantly enhances the photocatalytic efficiency of the Pd NC/In2O3/HCM (donated as PIC) system, achieving an optimal value of 496.89 μmol∙g−1 over 5 h without the need for additional additives, 8.7-fold higher than that of the pristine In2O3. Experimental and theoretical results reveal that the substantial enhancement in CO2 photoreduction performance can be attributed to the ultra-low resistance (122 Ω) interfaces within the PIC system, facilitating accelerated transfer of photogenerated electrons. This work provides a strategy for boosting CO2 photoreduction efficiency by the reduction of interface resistance to promote rapid photogenerated electron migration.