Photocatalytic CO2 Reduction Reaction Research Articles

Stable CO2 reduction under natural air on Ni–Sn hydroxide photocatalyst with dynamic renewable oxygen vacancies

Advanced photocatalysts are highly desired to activate the photocatalytic CO2 reduction reaction (CO2RR) with low concentration. Herein, the NiSn(OH)6 with rich surface lattice hydroxyls was synthesized to boost the activity directly under the natural air. Results showed that terminal Ni–OH could serve as donors to feed protons and generate oxygen vacancies (VO), thus beneficial to convert the activated CO2 (HCO3 −) mainly into CO (5.60 μmol g−1) in the atmosphere. It was flexible and widely applicable for a stable CO2RR from high pure to air level free of additionally adding H2O reactant, and higher than the traditional gas–liquid–solid (1.58 μmol g−1) and gas–solid (4.07 μmol g−1) reaction system both using high pure CO2 and plenty of H2O. The strong hydrophilia by the rich surface hydroxyls allowed robust H2O molecule adsorption and dissociation at VO sites to achieve the Ni–OH regeneration, leading to a stable CO yield (11.61 μmol g−1) with the enriched renewable VO regardless of the poor CO2 and H2O in air. This work opens up new possibilities for the practical application of natural photosynthesis.

Photocatalytic CO2 reduction of CuO-Zn1-xCuxO (ZCO)/Ti3C2Tx MXene heterojunctions with enhanced interfacial charge transfer

Photocatalytic CO2 reduction reaction (CO2RR) synthesis of recycled fuel is a promising pathway to assist the mitigating fossil fuel depletion. Finding efficient and inexpensive high performance CO2RR semiconductor photocatalysts is a giant challenge in the field of photocatalytic reduction. This work constructs the novel-designed interfacial Schottky junction of CuO-Zn1-xCuxO (ZCO)/Ti3C2Tx via electrostatic spinning and electrostatic self-assembly techniques. The catalysts exhibit tight contact heterogeneous interface companies with enhanced CO2 chemisorption capability and proved by various characterizations for efficient carrier separation and migration capacity. The optimized ZCO/Ti3C2Tx nanosheet composites significantly improved their photocatalytic performance. The best samples yielded 5.855 and 2.518 μmol g−1 h−1 of CO and CH4, which are 6 and 1.73 times higher than the conversion of ZCO, respectively, and maintain stability after four cycles without the use of sacrificial agents. In addition, the mechanism and reaction pathways of the photocatalytic process are proposed through In-situ diffuse reflectance Infrared Fourier Transform Spectroscopy (In-situ DRIFTS) and X-ray absorption near edge structure (XANES) analysis. This work provides a new semiconductor/co-catalyst system for the photocatalytic reduction of CO2 and demonstrates that Ti3C2Tx MXene is a hopeful and inexpensive co-catalyst.

A bifunctional catalyst derived from copper metal−organic framework for highly selective photocatalytic CO2 reduction and CO2 cycloaddition reaction

Highly efficient conversion of CO2 into valuable chemicals using green chemical reactions is attractive to the alleviation of global warming. Developing active catalysts with high selectivity remains challenging and is still in pursuit. Herein, a Cu-based metal−organic framework was successfully synthesized by a facile method and denoted as CuTIA. The obtained CuTIA with rich Lewis acid/base sites exhibited enhanced CO2 affinity and served as a bifunctional catalyst for CO2 conversion. To be specific, CuTIA converted CO2 into CH4 (103.78 μmol g−1 h−1) with a selectivity of 100 % under visible light irradiation. Besides, CuTIA drove CO2 cycloaddition reaction with epoxides to produce cyclic carbonates with a yield almost 100 % under mild conditions. This study provides a new perspective in the fabrication of bifunctional catalysts for enhancing CO2 conversion.

Internal electric field-modulated dual S-scheme ZnO@Co3O4/CsPbBr3 nanocages for highly active and selective photocatalytic CO2 reduction

The rational design of a step-scheme (S-scheme) heterojunction with strong internal electric field (IEF) and high redox capacity is a promising strategy for photocatalytic CO2 reduction reaction (CO2RR). However, the precise process of charge transport on the multi-interfaces remains a great challenge. Herein, a dual S-scheme heterojunction constructed in the ZnO@Co3O4/CsPbBr3 hierarchical nanocage was prepared for enhancing CO2RR activity. Without sacrificial agent and photosensitizer, the optimal photocatalyst exhibits a competitive CH4 yield rate of 238.8 μmol g−1h−1 with high selectivity (90.9%), affording an apparent quantum efficiency of 4.6 % at 400 nm, outperforming most previously comparable photocatalysts. In situ X-ray photoelectron spectroscopy (in situ XPS), photoelectrochemical measurement and theoretical calculation verifies the dual S-schematic charge-transport pathway. The remarkably improved performance in CO2RR is due to the rapid charge separation through O-Co-Br bridge driven by the strong internal electric field. This research furnishes a new insight to reveal dynamic charge transfer mechanism for CO2 conversion applications.

Unveiling Advancements: Trends and Hotspots of Metal-Organic Frameworks in Photocatalytic CO2 Reduction.

Metal-organic frameworks (MOFs) are robust, crystalline, and porous materials featured by their superior CO2 adsorption capacity, tunable energy band structure, and enhanced photovoltaic conversion efficiency, making them highly promising for photocatalytic CO2 reduction reaction (PCO2RR). This study presents a comprehensive examination of the advancements in MOFs-based PCO2RR field spanning the period from 2011 to 2023. Employing bibliometric analysis, the paper scrutinizes the widely adopted terminology and citation patterns, elucidating trends in publication, leading research entities, and the thematic evolution within the field. The findings highlight a period of rapid expansion and increasing interdisciplinary integration, with extensive international and institutional collaboration. A notable emphasis on significant research clusters and key terminologies identified through co-occurrence network analysis, highlighting predominant research on MOFs such as UiO, MIL, ZIF, porphyrin-based MOFs, their composites, and the hybridization with photosensitizers and molecular catalysts. Furthermore, prospective design approaches for catalysts are explored, encompassing single-atom catalysts (SACs), interfacial interaction enhancement, novel MOF constructions, biocatalysis, etc. It also delves into potential avenues for scaling these materials from the laboratory to industrial applications, underlining the primary technical challenges that need to be overcome to facilitate the broader application and development of MOFs-based PCO2RR technologies.

Reinforcing 2D Single-Crystal Bi2O2CO3 with Additional Interlayer Carbonates by CO2-Assisted Solid-to-Solid Phase Transition.

A facile gaseous CO2 mediated solid-to-solid transformation principle is adopted to insert additional CO3 2- anions into the thin single-crystal nanosheets of Bi2O2CO3, which is built of periodic arrays of intrinsic CO3 2- anions and (Bi2O2)2+ layers. The additional CO3 2- anions create abundant defects. The Bi2O2CO3 nanosheets with rich interlayer CO3 2- exhibit superior electronic properties and charge transfer kinetics than the pristine single-crystal 2D Bi2O2CO3 and display enhanced catalytic activity in photocatalytic CO2 reduction reaction and the photocatalytic oxidative degradation of organic pollutants. This work thus illustrates interlayer engineering as a flexible means to build layered 2D materials with excellent properties.

Surface Coordination Environment Engineering on PtxCu1-x Alloy Catalysts for the Efficient Photocatalytic Reduction of CO2 to CH4.

Alloy catalysts have been reported to be robust in catalyzing various heterogeneous reactions due to the synergistic effect between different metal atoms. In this work, aimed at understanding the effect of the coordination environment of surface atoms on the catalytic performance of alloy catalysts, a series of PtxCu1-x alloy model catalysts supported on anatase-phase TiO2 (PtxCu1-x/Ti, x = 0.4, 0.5, 0.6, 0.8) were developed and applied in the classic photocatalytic CO2 reduction reaction. According to the results of catalytic performance evaluation, it was found that the photocatalytic CO2 reduction activity on PtxCu1-x/Ti showed a volcanic change as a function of the Pt/Cu ratio, the highest CO2 conversion was achieved on Pt0.5Cu0.5/Ti, with CH4 as the main product. Further systematic characterizations and theoretical calculations revealed that the equimolar amounts of Pt and Cu in Pt0.5Cu0.5/Ti facilitated the generation of more Cu-Pt-paired sites (i.e., the higher coordination number of Pt-Cu), which would favor a bridge adsorption configuration of CO2 and facilitate the electron transfer, thus resulting in the highest photocatalytic CO2 reduction efficiency on Pt0.5Cu0.5/Ti. This work provided new insights into the design of excellent CO2 reduction photocatalysts with high CH4 selectivity from the perspective of surface coordination environment engineering on alloy catalysts.

Constructing B─N─P Bonds in Ultrathin Holey g-C3N4 for Regulating the Local Chemical Environment in Photocatalytic CO2 Reduction to CO.

The lack of intrinsic active sites for photocatalytic CO2 reduction reaction (CO2RR) and fast recombination rate of charge carriers are the main obstacles to achieving high photocatalytic activity. In this work, a novel phosphorus and boron binary-doped graphitic carbon nitride, highly porous material that exhibits powerful photocatalytic CO2 reduction activity, specifically toward selective CO generation, is disclosed. The coexistence of Lewis-acidic and Lewis-basic sites plays a key role in tuning the electronic structure, promoting charge distribution, extending light-harvesting ability, and promoting dissociation of excitons into active carriers. Porosity and dual dopants create local chemical environments that activate the pyridinic nitrogen atom between the phosphorus and boron atoms on the exposed surface, enabling it to function as an active site for CO2RR. The P-N-B triad is found to lower the activation barrier for reduction of CO2 by stabilizing the COOH reaction intermediate and altering the rate-determining step. As a result, CO yield increased to 22.45µmolg-1h-1 under visible light irradiation, which is ≈12 times larger than that of pristine graphitic carbon nitride. This study provides insights into the mechanism of charge carrier dynamics and active site determination, contributing to the understanding of the photocatalytic CO2RR mechanism.

Photocatalytic CO2 Reduction Using Mixed Catalytic Systems Comprising an Iron Cation with Bulky Phenanthroline Ligands.

This study reports on efficient photocatalytic CO2 reduction reactions using mixed catalytic systems of an Fe ion source and various 1,10-phenanthroline derivatives (R1R2p) as ligands in the presence of triethanolamine (TEOA). As the relatively bulky substituents at positions 2 and 9 of R1R2p weakened the ability to coordinate to the Fe ion, the Fe ion formed TEOA complexes. The free R1R2p accepted an electron from the reduced photosensitizer through proton-coupled electron transfer (PCET) using protons of TEOA dissolved in a CH3CN solution in a CO2 atmosphere as the initial step of the catalytic cycle. Although the mixed system of the nonsubstituted 1,10-phenanthroline generates a stable tris(phenanthroline)-Fe(II) complex in solution, this complex could not function as a CO2 reduction catalyst. The mechanism in which R1R2p interacts with the Fe ion after PCET was proposed for this efficient photocatalytic CO2 reduction. The proposed photocatalytic system using the 2,9-di-sec-butyl-phenanthroline ligand could produce CO with high efficiency (quantum yield of 8.2%) combined with a dinuclear Cu(I) complex as a photosensitizer.

Hetero-Motif Molecular Junction Photocatalysts: A New Frontier in Artificial Photosynthesis.

ConspectusTo cope with the increasingly global greenhouse effect and energy shortage, it is urgent to develop a feasible means to convert anthropogenic excess carbon dioxide (CO2) into energy resources. The photocatalytic CO2 reduction reaction (CO2RR) coupled with the water oxidation reaction (WOR), known as artificial photosynthesis, is a green, clean, and promoting strategy to deal with the above issues. Among the reported photocatalytic systems for CO2 reduction, the main challenge is to achieve WOR simultaneously due to the limited charge separation efficiency and complicated dynamic process. To address the problem, scientists have assembled two nanosemiconductor motifs for CO2RR and WOR into a heterojunction photocatalyst to realize artificial photosynthesis. However, it is difficult to clearly explore the corresponding catalytic mechanism and establish an accurate structure-activity relationship at the molecular level for their aperiodic distribution and complicated structural information. Standing on the shoulders of the heterojunction photocatalysts, a new-generation material, hetero-motif molecular junction (HMMJ) photocatalysts, has been developed and studied by our laboratory. A hetero-motif molecular junction is a class of crystalline materials with a well-defined and periodic structure, adjustable assembly mode, and semiconductor-like properties, which is composed of two predesigned motifs with oxidation and reduction, respectively, by coordination or covalent bonds. The intrinsic properties make these catalysts susceptible to functional modifications to improve light absorption and electrical conductivity. The small size and short distance of the motifs can greatly promote the efficiency of photogenerated electron-hole separation and migration. Based on these advantages, they can be used as potential excellent photocatalysts for artificial photosynthesis. Notably, the explicit structural information determined by single-crystal or powder X-ray diffraction can provide a visual platform to explore the reaction mechanism. More importantly, the connection number, spatial distance, interaction, and arrangement mode of the structural motifs can be well-designed to explore the detailed structure-activity relationship that can be hardly studied in nanoheterojunction photocatalyst systems. In this regard, HMMJ photocatalysts can be a new frontier in artificial photosynthesis and serve as an important bridge between molecular photocatalysts and solid photocatalysts. Thus, it is very important to summarize the state-of-the-art of the HMMJ photocatalysts used for artificial photosynthesis and to give in-depth insight to promote future development.In this Account, we have summarized the recent advances in artificial photosynthesis using HMMJ photocatalysts, mainly focusing on the results in our lab. We present an overview of current knowledge about developed photocatalytic systems for artificial photosynthesis, introduce the design schemes of the HMMJ photocatalysts and their unique advantages as compared to other photocatalysts, summarize the construction strategies of HMMJ photocatalysts and their application in artificial photosynthesis, and explain why hetero-motif molecular junctions can be promising photocatalysts and show that they provide a powerful platform for studying photocatalysis. The structure-activity relationship and charge separation dynamics are illustrated. Finally, we bring our outlook on present challenges and future development of HMMJ photocatalysts and their potential application prospects on other photocatalytic reaction systems. We believe that this Account will afford important insights for the construction of high-efficiency photocatalysts and guidance for the development of more photocatalytic systems in an atom-economic, environmentally friendly, and sustainable way.

Ab initio modelling of photocatalytic CO2 reduction reactions over Cu/TiO2 semiconductors including the electronic excitation effects

Photocatalysis is a promising method for reducing CO2 in an environmentally friendly way. Despite extensive experimental studies, theoretical studies lag behind and often resort to describing catalysts in the excited state, while the reaction mechanism is mostly studied at the ground level. We theoretically calculate a full reaction mechanism of CO2 reduction to CO in the excited state for five surfaces: Cu(111), anatase(110), rutile(101) and Cu/anatase, Cu/rutile using the ΔSCF approach. We show that excited states considerably lower activation barriers, making it necessary in describing the experimental performance. The density functional theory calculations in the excited state are used to construct a microkinetic model, which is used to predict the performance of each catalytic surface. We show that Cu(111) is photocatalytically inactive, TiO2 is only active in the UV range and catalyzes water splitting. Only Cu/rutile is active for CO2 reduction to CO, while Cu/anatase produces more H2.

Synergistically enhancing CO2 adsorption/activation and electron transfer in ZIF-67/Ti3C2Tx MXene for boosting photocatalytic CO2 reduction

To enhance the photocatalytic efficiency of ZIF-67 (Zeolitic Imidazolate Framework-67), we integrated it with Ti3C2Tx MXene through in-situ synthesis and assessed the effects of different MXene concentrations on photocatalytic activity. We identified ZIF-67/Ti3C2Tx MXene as the optimal catalyst (denoted as ZT-450), yielding CO, CH4, and H2 at 62.7, 6.7, and 7.3 μmol g−1, respectively. The CO productive rate achieved by ZT-450 exhibits a substantial enhancement, outperforming both ZIF-67 and Ti3C2Tx by factors of 16.1 and 4.8, respectively. After introducing Ti3C2Tx in ZIF-67, CO2 adsorption ability achieves 127.90 μmol g−1, much higher than those of pure ZIF-67 and Ti3C2Tx. Combining Density Functional Theory (DFT) calculations, we established that introducing Ti3C2Tx in ZIF-67 facilitates rapid electron transfer and improves light absorption, CO2 activation. In-situ DRIFTS measurements of photocatalytic CO2 reduction reaction (CO2RR) on ZIF-67/Ti3C2Tx MXene composite were employed to reveal the emergence of intermediates such as *COOH, *CHO, *OCH3, etc., and elucidate the mechanism accordingly. This research contributes to the advancement of photocatalytic CO2RR, offering insights into applying Ti3C2Tx MXene in photocatalysis.

Construction of a visible light responsive dual Z-scheme NH2-MIL-101(Fe)/CdS/g-C3N4 ternary heterojunction photocatalyst for efficient CO2 photoreduction to methanol

The photocatalytic CO2 reduction reaction using various semiconductors is exceedingly difficult due to the recombination of photo-exited electron-hole (e−, h+), inefficient irradiated light utilization, and lower adsorption capacity of CO2. An efficient design of the photocatalyst system is required to address this issue. The metal–organic frameworks (MOFs), particularly NH2-MIL-101(Fe) (NML-101(Fe)), have demonstrated exceptional efficiency in CO2 adsorption, and reduction because of its large surface area, efficient charge separation capacity, and ligand-to-metal charge transfer effect (LMCT). The synergistic effect of semiconductors CdS, g-C3N4 (GCN), and metal–organic framework on efficient photocatalytic CO2 conversion to CH3OH was investigated here. The successful synthesis and design of a dual Z-scheme NML-101(Fe)/CdS/GCN (NMCG(X)) ternary hetero-nanostructured system (THS) was demonstrated, in which CdS nanoparticles and NML-101(Fe) are deposited on the surface of GCN to form a dual Z-scheme mechanism with excellent photocatalytic performance. After 8 h of visible light irradiation, NMCG8 nanocomposites containing 37.5 % GCN, 25 % CdS, and 37.5 % NML-101(Fe) exhibit 1.53 times higher methanol production (53.89 µmolg−1) than pure NML-101(Fe) (35.11 µmolg−1). The efficient reduction of CO2 was largely attributed to the systematic transportation of photo-exited e− and h+ mediated by the dual Z-scheme mechanism, as demonstrated by PL spectra, electrochemical impedance spectra (EIS) studies, and Transient photocurrent response testing.

0D/3D heterostructure of perovskite Cs2CuBr4 quantum dots/Bi2O3 microflower as a step-scheme photocatalyst for enhanced CO2 reduction

Exploring highly-efficient photocatalytic materials to convert CO2 into clean energy fuels is of great significance. Herein, lead-free perovskite Cs2CuBr4 quantum dots (QDs) were loaded onto Bi2O3 microflower to construct a 0D/3D heterostructure of Cs2CuBr4/Bi2O3 (CCB/Bi2O3) for photocatalytic CO2 reduction reaction (CO2 RR). The developed 0D/3D CCB/Bi2O3 heterostructure exhibited dramatically enhanced CO2 RR activity, with an electron consumption rate (Relectron) up to 322.12 μmol g−1h−1, which was 3.16 folds that of pure Cs2CuBr4 QDs. The improvement of CO2 RR activity was originated from the promoted carrier separation and transfer, as well as retainment of strongly reducing electrons induced by the step-scheme electron transfer mode, as authenticated by in-situ X-ray photoelectron spectra (XPS), electron paramagnetic resonance (EPR), and density function theory (DFT) calculation. The CO2 RR pathway was unveiled by in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The innovation of perovskite QDs-based step-scheme heterostructures can throw inspiration on designing high-performance photocatalysts applied in artificial photosynthesis.

Reasonable design pentamerous artificial photosynthesis system for efficient overall CO2 reduction

Inspired by the photosynthesis of green plants in nature, an artificial photosynthesis system of MF/Co-BWO/CPB-Cu with “root”, “trunk” and “leaf” is designed in this study, realizing efficient overall photocatalytic CO2 reduction reaction (CO2RR). Melamine foam (MF) with strong hydrophilicity and abundant porosity is selected as “root” and “trunk”, which can store and transfer liquid H2O. For the “leaf” design, Bi2WO6 and CsPbBr3 are selected as oxidation and reduction photocatalysts, respectively, which would generate Bi2WO6/CsPbBr3 S-scheme heterojunction. CuS and CoO as reduction and oxidation centers are also introduced into photosynthesis system, respectively. CuS plays an important role in CO2 adsorption and activation, while CoO could promote H2O oxidation and supply proton. Moreover, Co-BWO/CPB-Cu as “leaf” could trigger the “transpiration” from MF via photo-thermal effect, inducing the formation of gas–solid biphase CO2RR system. As a result, the artificial photosynthesis system of MF/Co-BWO/CPB-Cu exhibits the efficient CO2RR efficiency.

Decoration of cyanamide groups to tune the surface electronic structures of semiconductor photocatalysts for efficient solar driven CO2 reduction

The using of reductive cocatalysts to dictate the transfer path of electrons towards targeting products is indispensable for photocatalytic CO2 reduction reaction (CRR). However, the development of low-cost and highly selective cocatalysts for photocatalytic CRR remains a daunting challenge. Herein, a functional molecule decoration strategy is proposed to tune the surface electronic structures of semiconductor photocatalysts, in order to promote their photocatalytic performance in CRR. We employ cyanamide groups as the chemical modifiers to regulate the CRR performance of solid solution metal sulphide photocatalysts. The synthesized photocatalysts exhibit excellent photocatalytic performance in CRR, and the highest CO evolution rate exceeds 1400 μmol g−1h−1, being among the best results reported to date. Multiple characterizations in combination with theoretical simulations further demonstrate that the decorated cyanamides do not act as active sites, but changes the electronic structures of the neighboring surface lattice metal atoms and decreases the kinetic barrier of the rate determining *CO2→*COOH step, thereby making the surface much more active for photocatalytic CRR. These findings explicitly verify the effectiveness of the functional molecule decoration strategy in promoting the CRR performance of photocatalysts, and also open up a new pathway for the development of highly efficient and selective catalysts for specific catalytic reactions.

Boosting CO2 Photoreduction to Formate or CO with High Selectivity over a Covalent Organic Framework Covalently Anchored on Graphene Oxide

AbstractCovalent organic frameworks (COFs) have been widely studied in photocatalytic CO2 reduction reaction (CO2RR). However, pristine COFs usually exhibit low catalytic efficiency owing to the fast recombination of photogenerated electrons and holes. In this study, we fabricated a stable COF‐based composite (GO‐COF‐366‐Co) by covalently anchoring COF‐366‐Co on the surface of graphene oxide (GO) for the photocatalytic CO2 reduction. Interestingly, in absolute acetonitrile (CH3CN), GO‐COF‐366‐Co shows a high selectivity of 94.4 % for the photoreduction of CO2 to formate, with a formate yield of 15.8 mmol/g, which is approximately four times higher than that using the pristine COF‐366‐Co. By contrast, in CH3CN/H2O (v : v=4 : 1), the main product for the photocatalytic CO2 reduction over GO‐COF‐366‐Co is CO (96.1 %), with a CO yield as high as 52.2 mmol/g, which is also approximately four times higher than that using the pristine COF‐366‐Co. Photoelectrochemical experiments demonstrate the covalent bonding of COF‐366‐Co and GO to form the GO‐COF‐366‐Co composite facilitates charge separation and transfer significantly, thereby accounting for the enhanced catalytic activity. In addition, theoretical calculations and in situ Fourier transform infrared spectroscopy reveal H2O can stabilize the *COOH intermediate to further form a *CO intermediate via O−H(aq)⋅⋅⋅O(*COOH) hydrogen bonding, thus explaining the regulated photocatalytic performance.

Boosting CO2 Photoreduction to Formate or CO with High Selectivity over a Covalent Organic Framework Covalently Anchored on Graphene Oxide.

Covalent organic frameworks (COFs) have been widely studied in photocatalytic CO2 reduction reaction (CO2 RR). However, pristine COFs usually exhibit low catalytic efficiency owing to the fast recombination of photogenerated electrons and holes. In this study, we fabricated a stable COF-based composite (GO-COF-366-Co) by covalently anchoring COF-366-Co on the surface of graphene oxide (GO) for the photocatalytic CO2 reduction. Interestingly, in absolute acetonitrile (CH3 CN), GO-COF-366-Co shows a high selectivity of 94.4 % for the photoreduction of CO2 to formate, with a formate yield of 15.8 mmol/g, which is approximately four times higher than that using the pristine COF-366-Co. By contrast, in CH3 CN/H2 O (v : v=4 : 1), the main product for the photocatalytic CO2 reduction over GO-COF-366-Co is CO (96.1 %), with a CO yield as high as 52.2 mmol/g, which is also approximately four times higher than that using the pristine COF-366-Co. Photoelectrochemical experiments demonstrate the covalent bonding of COF-366-Co and GO to form the GO-COF-366-Co composite facilitates charge separation and transfer significantly, thereby accounting for the enhanced catalytic activity. In addition, theoretical calculations and in situ Fourier transform infrared spectroscopy reveal H2 O can stabilize the *COOH intermediate to further form a *CO intermediate via O-H(aq)⋅⋅⋅O(*COOH) hydrogen bonding, thus explaining the regulated photocatalytic performance.

Recent advances in novel materials for photocatalytic carbon dioxide reduction

AbstractThe conversion of CO2 into chemical fuels, which can be stored and utilized through photocatalysis, represents an effective, environmentally friendly, and sustainable means to address both environmental concerns and energy shortages. CO2, as a stable oxidation product, poses challenges for reduction through light energy alone, necessitating the use of catalysts. Thus, a crucial aspect of CO2 photocatalytic reduction technology lies in the development of effective photocatalysts. Based on the basic principle of PCRR (photocatalytic CO2 reduction reaction), the review provides a detailed introduction to the core issues in PCRR process, including the relationship between band gap and catalyst reduction performance, effective utilization of photogenerated carriers, product selectivity, and methods for product analysis. Then, the recent research progresses of various photocatalysts are reviewed in the form of research examples combined with the above basic principles. Finally, this review summarizes and provides insights into the effective techniques for enhancing the photocatalytic activity of CO2, while also offering future prospects in this field.

Carbon nitride nanosheet-supported CuO for efficient photocatalytic CO2 reduction with 100% CO selectivity.

The optimal ratio of reaction solutions resulted in excellent performance and product selectivity of CuO/g-C3N4 composites in the photocatalytic CO2 reduction reaction. A pH-dependent chemical exchange saturation transfer (CEST) imaging nuclear magnetic resonance (NMR) method was used to confirm that CuO modification improves the adsorption capacity of CO2.