Photocatalytic Conversion Of CO2 Research Articles

Simultaneous Photocatalytic CO2 Reduction and H2O Oxidation Under Non-Sacrificial Ambient Conditions.

The utilization of CO2, H2O, and solar energy is regarded as a sustainable route for converting CO2 into chemical feedstocks, paving the way for carbon neutrality and reclamation. However, the simultaneous photocatalytic CO2 reduction and H2O oxidation under non-sacrificial ambient conditions is still a significant challenge. Researchers have carried out extensive exploration and achieved dramatic developments in this area. In this review, we first primarily elucidate the principles of two half-reactions in the photocatalytic conversion of CO2 with H2O, i. e., CO2 reduction by the photo-generated electrons and protons, and H2O oxidation by the photo-generated holes without sacrificial agents. Subsequently, the strategies to promote two half-reactions are summarized, including the vacancy/facet/morphology design, adjacent redox site construction, and Z-scheme heterojunction development. Finally, we present the advanced in situ characterizations and future perspectives in this field. This review aims to provide fresh insights into effectively simultaneous photocatalytic CO2 reduction and H2O oxidation under non-sacrificial ambient conditions.

A robust floating oxygen-doped graphitic carbon nitride sheet for efficient photocatalytic CO2 conversion

Photocatalytic CO2 reduction offers a promising approach for converting CO2 into valuable chemicals. However, typical conversion systems suffer from inefficient CO2 mass transfer and complex recycling processes. In this study, we developed a floating sheet as a robust photocatalytic CO2 conversion system by integrating graphitic carbon nitride (CN) nanosheets onto polytetrafluoroethylene (PTFE) fiber membrane, followed by oxygen (O) doping into the CN (CN-O) via oxygen-plasma treatment. The floatable CN-O/PTFE sheet exhibits slight wettability in water under 0.25 MPa of CO2 pressure in our reactor system, facilitating the delivery of dissolved CO2 to the CN-O photocatalyst surface. O-doping enhances the visible light absorption and improves the separation and transport efficiency of photogenerated electrons and holes due to O-doping-induced states in CN. Consequently, the floating CN-O/PTFE system achieves an exceptional photocatalytic CO2 conversion rate of 102.3 μmol g-1h−1, approximately 4.8 times higher than a conventional CN-powder dispersion system in water. Moreover, the sheet demonstrates excellent cycling durability, with no significant exfoliation of the catalytic layer or reduction in CO2 photoreduction activity after 20 consecutive cycles. This study presents a novel approach to designing photocatalytic systems for efficient CO2 conversion.

Slow-light-driven photocatalytic CO2 reduction to CH4 mediated by photonic crystal Graphdiyne-Cu/ZnO Z-scheme system

Developing photocatalysts with high activity and selectivity remains a significant challenge in the field of CO2 photoreduction for producing valuable chemical or fuel products under mild conditions. Herein, photonic crystal (PC) GDY-Cu/ZnO was constructed through the in-situ induced growth of graphdiyne (GDY) on PC Cu/ZnO surface via H2-reduction for efficient photoreduction of CO2 to CH4. With the aid of photonic crystal structure, PC GDY-Cu/ZnO exhibits a distinctive red-edge slow light region which can significantly improve the utilization efficiency of visible light and intensify photo-catalysis. Additionally, the formed all-solid-state Z-scheme system efficiently accelerates photoelectron migration, facilitating e-/h+ separation. Thirdly, the surface GDY, along with the enrich oxygen vacancies generated during H2 reduction, enhances the adsorption and activation toward CO2 and H2O on PC GDY-Cu/ZnO interface. In consequence, PC GDY-Cu/ZnO demonstrates highly photocatalytic conversion of CO2 to CH4, achieving a CH4 yield of 33.67 μmol·g−1·h−1 with 93.3 % selectivity via slow-light-driven photocatalysis CO2 reduction. This work provides an efficient strategy to modify ZnO for the efficient photoreduction of CO2 to CH4.

Boosted Photocatalytic CO2 Conversion of a Cs2AgBiBr6@Co3O4 Composite with High Activity and Selectivity under Low-Concentration CO2 and Natural Sunlight

To explore high-efficiency photocatalysts that can operate under low-concentration CO2 and natural light conditions remains a significant challenge in the field of photocatalysis. Here, we have constructed lead-free Cs2AgBiBr6@Co3O4 (CABB@Co3O4) composites with compact heterogenous interfaces, enhanced CO2 adsorption capability and excellent photoelectronic characteristics. The optimal CABB@Co3O4 heterojunction exhibits nearly 100% selectivity for visible-light-driven CO2 to CO conversion with the high catalytic efficiency and stability in high-purity and diluted CO2. Importantly, the CABB@Co3O4 photocatalyst is one of a few examples to drive photocatalytic CO2 reduction under the 5v% CO2 and natural sunlight, exhibiting a linear relationship between CO evolution rate and light intensity. The outstanding photocatalytic performance mainly originates from the suppressed carrier recombination and the decreased energy barrier for the formation of the key *COOH intermediate. This work provides prospective guidance for designing efficient photocatalysts toward CO2 conversion under the actual environmental conditions.

Emerging 2D MXene quantum dots for catalytic conversion of CO2

MXene is an emerging material for converting carbon dioxide (CO2) into valuable products because of its robust physical and chemical properties. The high specific surface area (SSA), conductivity, and stability of the MXene make it an attractive material for the catalytic conversion of CO2. The pristine MXene possessed poor catalytic properties as compared to their composites. This study briefly discussed the magical properties and advanced synthesizing routes of MXene and MXene quantum dots (MQDs). In addition, the oxidation of the MXene is responsible for altering its chemical composition, and the factors used to oxidize the MXene were discussed in detail. Furthermore, the mechanism of hydrogenation, chemical, electrocatalytic, and photocatalytic reduction of CO2 has been discussed. Finally, the MXene quantum dots (MQDs) for photocatalytic conversion of CO2 for the first time also present the future challenges and prospectus associated with MXene.

Unraveling the roles of atomically-dispersed Au in boosting photocatalytic CO2 reduction and aryl alcohol oxidation

Atomically-dispersed metal-based materials represent an emerging class of photocatalysts attributed to their high catalytic activity, abundant surface active sites, and efficient charge separation. Nevertheless, the roles of different forms of atomically-dispersed metals (i.e., single-atoms and atomic clusters) in photocatalytic reactions remain ambiguous. Herein, we developed an ethylenediamine (EDA)-assisted reduction method to controllably synthesize atomically dispersed Au in the forms of Au single atoms (AuSA), Au clusters (AuC), and a mixed-phase of AuSA and AuC (AuSA+C) on CdS. In addition, we elucidate the synergistic effect of AuSA and AuC in enhancing the photocatalytic performance of CdS substrates for simultaneous CO2 reduction and aryl alcohol oxidation. Specifically, AuSA can effectively lower the energy barrier for the CO2→*COOH conversion, while AuC can enhance the adsorption of alcohols and reduce the energy barrier for dehydrogenation. As a result, the AuSA and AuC co-loaded CdS show impressive overall photocatalytic CO2 conversion performance, achieving remarkable CO and BAD production rates of 4.43 and 4.71 mmol g−1 h−1, with the selectivities of 93% and 99%, respectively. More importantly, the solar-to-chemical conversion efficiency of AuSA+C/CdS reaches 0.57%, which is over fivefold higher than the typical solar-to-biomass conversion efficiency found in nature (ca. 0.1%). This study comprehensively describes the roles of different forms of atomically-dispersed metals and their synergistic effects in photocatalytic reactions, which is anticipated to pave a new avenue in energy and environmental applications.

Precisely Tuning Band Gaps of Hexabenzocoronene-Based MOFs Toward Enhanced Photocatalysis.

Precise adjusting the band gaps in metal-organic frameworks (MOFs) is crucial for improving their visible-light absorption capacity during photocatalysis, presenting both a formidable challenge and a charming opportunity. This present study employed a symmetry-reduction strategy to pre-design six novel 4-connected ligands with systematic substituents (-NO2, -H, -tBu, -OCH3, -OH and -NH2) and synthesized the corresponding pillared-layer Zr-MOFs (NKM-668) retaining the hexaphenylbenzene fragment. Subsequently, the NKM-668 MOFs were transformed into large-π-conjugated hexabenzocoronene-based MOFs (pNKM-668) via the Scholl reaction. These twelve MOFs exhibited broad and tunable band gaps over 1.41 eV (ranging from 3.25 eV to 1.84 eV), and the photocatalytic CO2 conversion rate raised by 33.2-fold. This study not only enriches the type of hexaphenylbenzene-based MOFs, but also paves the way for nanographene-containing MOFs in the further application of photocatalysis.

Modulating stacking mode and molecular polarization in CTF/molecule heterojunction for meliorating photocatalytic CO2 conversion with nearly 100% CO selectivity

Herein, two conjugated molecules, i.e., D-π-A TAPT and non-D-A TAPB, are finely designed to incorporate with covalent triazine framework (CTF) in A-A and A-B stacking mode via π-π interaction, respectively. The transient photocurrent response of the generated AA-CTF/TAPT Z-Scheme heterostructure is 1.14 × 10-7 A, significantly higher than that of the other two metal-free heterostructures (AA-CTF/TAPB and AB-CTF/TAPT). The promoted photocarrier transportation is attributed to strong polarization (dipole moment = 2.634 D) imposed by the D-π-A effect in TAPT that motivates the interfacial charge separation, and the coexisting charge transfer channel built by the ordered A-A stacking mode in AA-CTF that expedites the charge delivery. The photocatalytic CO2 conversion conducted by AA-CTF/TAPT gives the optimal CO conversion rate as 7.47 μmol·g−1·h−1, and with nearly 100 % product selectivity obtained, which is attributable to the lower energy barrier of CO desorption barrier (−1.07 eV) rather than that of CHO* formation (1.52 eV) for generating CH4.

A multifunctional platform based on ZIF-67 templated NiCo-LDH and Fe3O4 hollow spheres for photocatalytic CO2 conversion and supercapacitors

This work presented a series of hybrid materials F@P-LDHs exhibiting the core-shell structure with PPy as the interface modifier, explored as dual-functional materials for studying photocatalytic reduction of CO2 and electrochemical behaviors. F@P-LDHs served as photocatalysts, effectively convert CO2 into CO without using any sacrificial agents and photosensitizers via the gas-solid mode under the visible light irradiation. The generation rate of CO was as high as 10.32 μmol g−1h−1, which was 5.4 and 6.4 times higher than the original Fe3O4@PPy and NiCo-LDH. The well performance might be ascribed to the generation of type Z heterojunction with the interface modifier PPy, jointly accelerating the separation and migration of photo-generated charge carriers between Fe3O4@PPy and NiCo-LDH. Besides, F@P-LDHs were also developed as supercapacitors, and their electrochemical behaviors were investigated. Their good electrochemical performances were attributed to the synergistic effect among hollow Fe3O4 microspheres, polypyrrole and NiCo-LDH. Therefore, as dual-functional materials, the hybrid materials have great potential in the field of CO2 conversion and supercapacitors.

Addition of CuO to form CuO/TiO2 and CuO/ZnO heterojunctions for photocatalytic CO2 conversion to methanol

Photocatalytic conversion of carbon dioxide (CO2) to value-added products is a promising route towards sustainability. In this work, gas phase CO2 in presence of water vapor and UV irradiation source was converted to methanol using TiO2, ZnO, CuO/TiO2 and CuO/ZnO photocatalysts. Characterization by physico-chemical, optical and First-principle based techniques revealed that CuO/TiO2 possessed increased oxygen vacancy, highest average electron lifetime, transfer rate, injection efficiency and highest separation efficiency. The maximum methanol (∼28 %) yield of CuO/TiO2 is ascribed due to combined effect of heterojunction formation and increment in surface oxygen vacancies by doping with CuO, acted as electron-trapping cocatalyst.

Emerging ZnO Semiconductors for Photocatalytic CO2 Reduction to Methanol.

Carbon recycling is poised to emerge as a prominent trend for mitigating severe climate change and meeting the rising demand for energy. Converting carbon dioxide (CO2) into green energy and valuable feedstocks through photocatalytic CO2 reduction (PCCR) offers a promising solution to global warming and energy needs. Among all semiconductors, zinc oxide (ZnO) has garnered considerable interest due to its ecofriendly nature, biocompatibility, abundance, exceptional semiconducting and optical properties, cost-effectiveness, easy synthesis, and durability. This review thoroughly discusses recent advances in mechanistic insights, fundamental principles, experimental parameters, and modulation of ZnO catalysts for direct PCCR to C1 products (methanol). Various ZnO modification techniques are explored, including atomic size regulation, synthesis strategies, morphology manipulation, doping with cocatalysts, defect engineering, incorporation of plasmonic metals, and single atom modulation to boost its photocatalytic performance. Additionally, the review highlights the importance of photoreactor design, reactor types, geometries, operating modes, and phases. Future research endeavors should prioritize the development of cost-effective catalyst immobilization methods for solid-liquid separation and catalyst recycling, while emphasizing the use of abundant and non-toxic materials to ensure environmental sustainability and economic viability. Finally, the review outlines key challenges and proposes novel directions for further enhancing ZnO-based photocatalytic CO2 conversion processes.

Regulating the Layer Stacking Configuration of CTF-TiO2 Heterostructure for Improving the Photocatalytic CO2 Reduction.

Herein, covalent triazine frameworks in eclipsed AA and staggered AB stacking modes are respectively used for the in-situ growth of TiO2, and two heterostructures are obtained. Due to the highly organized stacking of the molecular layer in CTF-AA that strengthens the interlayer interaction, the light absorption and carrier migration of CTF-AA/TiO2 are both enhanced in comparison to those of its component or CTF-AB/TiO2. Correspondently, the photocatalytic CO2 reduction reaction (CO2RR) of CTF-AA/TiO2 proffers 9.19 μmol·g-1·h-1 CH4 and 2.32 μmol·g-1·h-1 CO production, about 9.2 and 4.3 times greater than that of pristine TiO2, respectively. Even though the innate photoresponse of the triazine unit endows CTF-AB/TiO2 with augmented light capturing, its photocatalytic CO2 conversion is relatively insignificant. According to the analyses of the planar-averaged electron density difference and Bader charge, the unproductive CO2 efficiency might be due to the insufficient interfacial electron transfer from TiO2 to CTF-AB. Given that the ΔG (-3.22 eV) of CHO intermediate generation is lower than that of CO desorption (-1.23 eV), the reaction tends to further generate CH4 other than yielding CO. This study could shed fresh light over the reasonable design of effective photocatalytic heterostructures.

Bismuth-based photocatalysts enhanced by sulfur/oxygen vacancies for the selective reduction of carbon dioxide into methane

Reducing carbon dioxide (CO2) into methane (CH4) through photocatalysis technology can effectively decrease carbon emissions and ease the energy crisis. However, the low photocatalytic efficiency and high electron-hole recombination rates still hinder the large-scale utilization of photocatalysis. Vacancy engineering can reduce electron-hole pair complexation, however, the effects of oxygen (O) and sulfur (S) vacancies on the CO2 reduction properties of bismuth (Bi)-based photocatalysts are unclear. This study prepared different Bi-based photocatalysts, including α-Bi2O3, α-Bi2O3-X, Bi2S3, and Bi2S3-X. The introduction of vacancies was found to greatly increase the specific surface areas, effectively reduce electron-hole recombination, decrease charge transfer resistance, and enhance electron transfer, leading to enhanced CH4 production. Comparatively, Bi2S3-X has substantially demonstrated a superior efficiency in the photocatalytic conversion of CO2 to CH4 compared to Bi2S3, while α-Bi2O3-X exhibited slightly higher than α-Bi2O3. There are more S vacancies in Bi2S3-X (x=0.581) than O vacancies in α-Bi2O3-X (x=0.329), leading to its superior photocatalytic activity, with CO and CH4 production rates of 3.706 μmol·g−1·h−1 and 7.697 μmol·g−1·h−1, respectively. Moreover, the CH4 selectivity of Bi2S3-X reaches 67.50 %, which is 1.67 times that of α-Bi2O3-X. Therefore, Bi2S3-X holds great promise as a photocatalyst for CO2 reduction. This work proves that in Bi-based photocatalyst, S vacancy is more effective than O vacancy in enhancing the selective reduction of CO2 to CH4, offering a pathway for achieving selective CO2 reduction to CH4.

Hierarchical Ag3VO4 Nanorods as an Excellent Visible Light Photocatalyst for CO2 Conversion to Solar Fuels

The potential of photocatalytic CO2 conversion is significant for the production of fuels and chemicals, while simultaneously mitigating CO2 emissions and addressing environmental concerns. Despite the current drawbacks of single metal-based photocatalysts, such as lower performance, uncontrollable selectivity, and instability, this study focuses on the synthesis of Ag3VO4 nanorods using the sol–gel method. The goal is to create a highly effective catalyst for visible light-responsive CO2 conversion. The successful synthesis of Ag3VO4 nanorods with a nanorod structure, functional under visible light, resulted in the highest yields of CH4 and dimethyl ether (DME) at 271 and 69 µmole/g-cat, respectively. The optimized Ag3VO4 nanorods demonstrated performance improvements, with CH4 and DME production 6.4 times and 4.5 times higher than when using V2O5 samples. This suggests that Ag3VO4 nanorods facilitate electron transfer to CO2, offer short pathways for electron transfer, and create empty spaces within the nanorods as electron reservoirs, enhancing the photoactivity. The prolonged stability of Ag3VO4 in the CO2 conversion system confirms that the nanorod structure provides controllable selectivity and stability. Therefore, the fabrication of nanorod structures holds promise in advancing high-performance photocatalysts in the field of photocatalytic CO2 conversion to solar fuels.

Sulfur-vacancy induced asymmetric active site for Bi19S27Br3 nanorods photocatalyzes CO2 conversion to ethylene

The photocatalytic conversion of CO2 into high value-added C2 products remains a significant challenge due to the limited active sites and high energy barrier of C-C coupling process. Herein, the sulfur-vacancy was established on the surface of Bi19S27Br3 nanorods, leading to the electron on residual S atoms become unstable and active. Under the light irradiation, the photoexcited electron transfer from S atoms to neighboring Bi atoms to generate in-situ charge-polarized Bi(3-x)+ asymmetric active sites, which can enhance CO2 adsorption-activation capacity and regulate C-C coupling process for the C1 intermediate. The experimental results and theoretical calculation confirm that more charges aggregate around the induced Bi atoms, reducing the energy barrier of the C-C coupling reaction and improving C2H4 formation. Consequently, the sulfur-vacancy Bi19S27Br3 nanorods achieve efficient C2H4 generation through photocatalytic CO2 reduction, which C2H4 formation rate is 17.80 µmol g−1 after 5-hour photocatalytic reaction, with the product selectivity and electron selectivity of 49 % and 85 %, respectively, outperforming the low sulfur-vacancy Bi19S27Br3 nanorods by four-folds. This research provides new insights into the design of photocatalysts.

Z-scheme heterojunction enhanced photocatalytic performance for CO2 reduction to CH4.

Due to the high charge separation efficiency leading to high photocatalytic activity, there has been significant interest in enhancing the charge separation ability of photocatalysts by controlling the heterojunction structure. To investigate the effect of the heterojunction structure on the photocatalytic performance of composite catalysts and understand its corresponding mechanism, a Z-scheme ZnFe2O4/ZnO/CdS heterojunction was constructed using the ultrasound method and used for CO2 photoreduction. The Z-scheme heterojunction catalyst demonstrates elevated photocatalytic and charge separation efficiencies. Specifically, the conversion rate for the photocatalytic conversion of CO2 to CH4 reaches 105.9 μmol g-1 h-1, surpassing that of the majority of previously reported semiconductor photocatalysts like ZnFe2O4/CdS. This research offers a fresh perspective on the development of innovative heterojunction photocatalysts and broadens the utilization of ternary composite materials in CO2 photoreduction.

Biphase TiO2\\Zn-tetracarboxy-phthalocyanine twin S-scheme heterojunction nanowires with efficient charge transfer and CO2 photocatalytic conversion

Constructing heterojunction photocatalysts with proper charge transfer channels has been confirmed to be a promising strategy for CO2 photoreduction into chemical fuels. However, promoting photoinduced charge separation in traditional heterojunction catalysts still remains a big obstacle for practical applications. In this work, the TiO2(B)-Anatase\\ZnTcPc twin S-scheme heterojunctions are designed and constructed by loading Zn (II) tetracarboxy phthalocyanine (ZnTcPc) on the prepared TiO2(B)-Anatase biphase TiO2 nanowires by self-assemble strategy. The TiO2(B)-Anatase\\ZnTcPc twin S-scheme heterojunctions effectively promote charge transport across the multi-heterointerfaces and enhance visible light absorption and CO2 adsorption. Thus the optimized hybrid photocatalyst exhibits a remarkable photocatalytic CO2 reduction performance, and the CO yield reaches 237.8μmol g−1h−1. The CO2 photoreduction mechanism and charge transfer properties in the twin S-scheme heterojunction are also investigated and characterized. This research offers a viable approach to enhancing the heterojunction system for excellent photocatalytic performance.

Surface Modifications of Heterogeneous Photocatalysts for Photocatalytic Conversion of CO2 by H2O as the Electron Donor

AbstractThe photocatalytic conversion of CO2 using H2O over heterogeneous photocatalysts has attracted worldwide attention because it enables direct solar‐to‐chemical energy conversion. However, further development of this technology requires solutions to overcome the low formation rates of CO2 reduction products and their insufficient selectivity, mainly caused by the rapid charge recombination of photogenerated electron/hole pairs, competition for thermodynamically preferential H2 evolution from H2O, and the relatively low concentration of CO2 on the surface of the photocatalysts. Surface modification of heterogeneous photocatalysts is crucial for improving their formation rates and selectivity. This review article introduces four strategies for designing photocatalyst surfaces for the photocatalytic conversion of CO2 by H2O: (I) loading of an Ag cocatalyst, (II) utilisation of cocatalysts for H2O oxidation, (III) suppression of undesired H2 evolution, and (IV) loading of basic materials for CO2 adsorption. The strategies introduced in this review successfully enhanced the formation rates of the products and/or their selectivity in the heterogeneous photocatalytic conversion of CO2 by H2O.

Studying the productivity of sewage sludge (SS) components for photocatalytic CO2 transformation to CO and methane

AbstractEnergy-efficient photocatalytic CO2 conversion to sustainable solar fuels is a promising approach for simultaneously resolving energy and environmental concerns. The increased growth of sewage sludge necessitates research and innovation to propose more commercially viable options for lowering the socioeconomic and environmental complications associated with its current treatment. Sewage sludge can be applied to valuable products or used as a feedstock for energy production. According to the characterization results, the sewage sludge contains several metallic oxides (M), including Ni, Al, Mn, and Cu, and semiconductors (Fe2O3 and ZnO). According to the proposed mechanism, ZnO acts as an electron conductor between the Fe2O3 and the active sewage sludge due to forming an n–n type heterojunction. Under visible-light irradiation, photocatalytic CO2 reduction of sewage sludge was investigated using a fixed bed reactor. The CO2 reduction produced CO and CH4, with production rates of 9.76 and 4.20 µmol g−1 h−1, respectively, via the electrical conductivity in the sewage sludge elements. Furthermore, the impacts of photocatalyst loading, system reforming, light effect and pressure range were examined, where the methane yield at 0.1 g was 4.23 and 2.26 times significantly higher than at 0.05 and 0.2 g, correspondingly. With catalyst loadings of 0.1 and 0.2 g, the mono-oxide productivity was 1.69 and 2.58, notably greater, respectively. Moreover, the best yield of the CO and methane was obtained by using 0.3 bar as pressure and 10% methanol in H2O/CO2 as a reducing agent. Finally, using sewage sludge to produce a solar fuel based on the presence of active metallic oxide and semi-conductor heterojunctions provides novel insights from molecular and engineering perspectives into converting CO2 to a green fuel using wastewater sludge. Graphical abstract

Constructing type II heterojunction of 2D/1D Pg-C3N4/Ag3VO4 nanocomposite with high interfacial charge separation for boosting photocatalytic CO2 reduction under solar energy

The well-designed, template-free synthesis of 2D protonated g-C3N4 nanosheets (Pg-C3N4) coupled with novel 1D Ag3VO4 nanorods has been investigated to construct 2D/1D interface heterostructures with strong electrostatic interactions between the positively charged 2D Pg-C3N4 nanosheets and the negatively charged 1D Ag3VO4 nanorods. The coupling of Pg-C3N4 and Ag3VO4 with desirable characteristics resulted in a 2D/1D interface heterojunction with a type II charge carrier transfer mechanism, effectively maintaining and utilizing charge carriers. The 2D/1D Pg-C3N4/Ag3VO4 exhibited remarkable photocatalytic performance for CO2 conversion with H2O, resulting in maximum CH4 and dimethyl ether (DME) production of 352.3 and 130.9 µmol/g-cat, respectively. A quantum yield of 0.23 % for CH4 generation was achieved over the 2D/1D Pg-C3N4/Ag3VO4, which was 2.9 and 1.4 times higher than that of the Pg-C3N4 and Ag3VO4 samples, respectively. The improvement in photocatalytic performance primarily stems from the effective interaction between Pg-C3N4 and ternary Ag3VO4, leading to enhanced transfer and separation of photoinduced charge carriers through the creation of a type II heterojunction. The findings of this study are useful in designing template-free heterojunctions for photocatalytic CO2 conversion and other solar energy applications.