In situ fabrication of atomically adjacent dual-vacancy sites for nearly 100% selective CH4 production.

The photocatalytic CO2-to-CH4 conversion involves multiple consecutive proton-electron coupling transfer processes. Achieving high CH4 selectivity with satisfactory conversion efficiency remains challenging since the inefficient proton and electron delivery path results in sluggish proton-electron transfer kinetics. Herein, we propose the fabrication of atomically adjacent anion-cation vacancy as paired redox active sites that could maximally promote the proton- and electron-donating efficiency to simultaneously enhance the oxidation and reduction half-reactions, achieving higher photocatalytic CO2 reduction activity and CH4 selectivity. Taking TiO2 as a photocatalyst prototype, the operando electron paramagnetic resonance spectra, quasi in situ X-ray photoelectron spectroscopy measurements, and high-angle annular dark-field-scanning transmission electron microscopy image analysis prove that the VTi on TiO2 as initial sites can induce electron redistribution and facilitate the escape of the adjacent oxygen atom, thereby triggering the dynamic creation of atomically adjacent dual-vacancy sites during photocatalytic reactions. The dual-vacancy sites not only promote the proton- and electron-donating efficiency for CO2 activation and protonation but also modulate the coordination modes of surface-bound intermediate species, thus converting the endoergic protonation step to an exoergic reaction process and steering the CO2 reduction pathway toward CH4 production. As a result, these in situ created dual active sites enable nearly 100% CH4 selectivity and evolution rate of 19.4 µmol g-1 h-1, about 80 times higher than that of pristine TiO2. Thus, these insights into vacancy dynamics and structure-function relationship are valuable to atomic understanding and catalyst design for achieving highly selective catalysis.

Selective Photoreduction of CO2 to CH4 Triggered by Metal-Vacancy Pair Sites.

Selectively achieving the photoreduction of carbon dioxide (CO2) to methane (CH4) remains a significant challenge, which primarily arises from the complexity of the protonation process. In this work, we designed metal-vacancy pair sites in defective metal oxide semiconductors, which anchor the reactive intermediates with a bridged linkage for the selective protonation to produce CH4. As an example, oxygen-deficient Nb2O5 nanosheets are synthesized, in which the niobium-oxygen vacancy pair sites are demonstrated by X-ray photoelectron spectroscopy and electron paramagnetic resonance spectra. In situ Fourier transform infrared spectroscopy monitors the *CH3O intermediate, a key intermediate for CH4 production, during the CO2 photoreduction in oxygen-deficient Nb2O5 nanosheets. Importantly, the built metal-vacancy pair sites regulate the *CH3O formation step as a spontaneous process, making the reduction of CO2 to CH4 the preferred method. Therefore, the oxygen-deficient Nb2O5 nanosheets exhibit a CH4 formation rate of 19.14 µmol g-1 h-1, with an electron selectivity of ∼94.1%.

Nitrogen Doping-Roused Synergistic Active Sites in Perovskite Enabling Highly Selective CO2 Photoreduction into CH4.

The intricate protonation process in carbon dioxide reduction usually makes the product unpredictable. Thus, it is significant to control the reactive intermediates to manipulate the reaction steps. Here, we propose that the synergistic La-Ti active sites in the N-La2Ti2O7 nanosheets enable the highly selective carbon dioxide photoreduction into methane. In the photoreduction of CO2 over N-La2Ti2O7 nanosheets, in situ Fourier transform infrared spectra are utilized to monitor the *CH3O intermediate, pivotal for methane production, whereas such monitoring is not conducted for La2Ti2O7 nanosheets. Also, theoretical calculations testify to the increased charge densities on the Ti and La atoms and the regulated formation energy barrier of *CO and *CH3O intermediates by the constructed synergistic active sites. Accordingly, the methane formation rate of 7.97 µL h-1 exhibited by the N-La2Ti2O7 nanosheets, along with an electron selectivity of 96.6%, exceeds that of most previously reported catalysts under similar conditions.

Synthetic Leaves Based on Crystalline Olefin-Linked Covalent Organic Frameworks for Efficient CO2 Photoreduction with Water.

We report, for the first time, a new synthetic strategy for the preparation of crystalline two-dimensional olefin-linked covalent organic frameworks (COFs) based on aldol condensation between benzodifurandione and aromatic aldehydes. Olefin-linked COFs can be facilely crystallized through either a pyridine-promoted solvothermal process or a benzoic anhydride-mediated organic flux synthesis. The resultant COF leaf with high in-plane π-conjugation exhibits efficient visible-light-driven photoreduction of carbon dioxide (CO2) with water (H2O) in the absence of any photosensitizer, sacrificial agents, or cocatalysts. The production rate of carbon monoxide (CO) reaches as high as 158.1 µmol g-1 h-1 with near 100% CO selectivity, which is accompanied by the oxidation of H2O to oxygen. Both theoretical and experimental results confirm that the key lies in achieving exceptional photoinduced charge separation and low exciton binding. We anticipate that our findings will facilitate new possibilities for the development of semiconducting COFs with structural diversity and functional variability.

Spatial Heterogeneity and Strong Coupling of FeII /FeIII in an Individual Metal-Organic Framework Nanoparticle for Efficient CO2 Photoreduction.

The synthesis and characterization of an FeII /FeIII metal-organic framework (MOF) nanocrystal with spatial heterogeneity that arises from the non-uniform distribution of different valence states is disclosed. The FeII /FeIII -Ni Prussian blue analog (PBA) delivers superior photocatalytic performance in the selective CO2 reduction reaction thanks to the strong FeII /FeIII coupling, with CO yield up to 12.27 mmol g-1 h-1 and 90.6% selectivity under visible-light irradiation. Density functional theory calculation and experimental studies prove that the spatial heterogeneity of FeII /FeIII in the individual MOF nanocrystal not only directs and expedites the charge transfer within a catalyst particle but also creates the heterogeneity of catalytically-active Ni sites for efficient CO2 photoreduction. The current findings add to a growing literature of materials with compositional heterogeneity and provide a reference for future research.

2D Atomic Layers for CO2 Photoreduction.

Artificial photosynthesis can convert carbon dioxide into high value-added chemicals. However, due to the poor charge separation efficiency and CO2 activation ability, the conversion efficiency of photocatalytic CO2 reduction is greatly restricted. Ultrathin 2D photocatalyst emerges as an alternative to realize the higher CO2 reduction performance. In this review, the basic principle of CO2 photoreduction is introduced, and the types, advantages, and advances of 2D photocatalysts are reviewed in detail including metal oxides, metal chalcogenides, bismuth-based materials, MXene, metal-organic framework, and metal-free materials. Subsequently, the tactics for improving the performance of 2D photocatalysts are introduced in detail via the surface atomic configuration and electronic state tuning such as component tuning, crystal facet control, defect engineering, element doping, cocatalyst modification, polarization, and strain engineering. Finally, the concluding remarks and future development of 2D photocatalysts in CO2 reduction are prospected.

In-Plane Palladium and Interplanar Copper Dual Single-Atom Catalyst in Bulk-Like Carbon Nitride for Cascade CO2 Photoreduction.

Dual single-atom catalysts (DSACs) are promising for breaking the scaling relationships and ensuring synergistic effects compared with conventional single-atom catalysts (SACs). Nevertheless, precise synthesis and optimization of DSACs with specific locations and functions remain challenging. Herein, dual single-atoms are specifically incorporated into the layer-stacked bulk-like carbon nitride, featuring in-plane three-coordinated Pd and interplanar four-coordinated Cu (Pd1-Cu1/b-CN) atomic sites, from both experimental results and DFT simulations. Using femtosecond time-resolved transient absorption (fs-TA) spectroscopy, it is found that the in-plane Pd features a charge decay lifetime of 95.6 ps which is much longer than that of the interplanar Cu (3.07 ps). This finding indicates that the in-plane Pd can provide electrons for the reaction as the catalytically active site in both structurally and dynamically favorable manners. Such a well-defined bi-functional cascade system ensures a 3.47-fold increase in CO yield compared to that of bulk-like CN (b-CN), while also exceeding the effects of single Pd1/b-CN and Cu1/b-CN sites. Furthermore, DFT calculations reveal that the inherent transformation from s-p coupling to d-p hybridization between the Pd site and CO2 molecule occurs during the initial CO2 adsorption and hydrogenation processes and stimulates the preferred CO2-to-CO reaction pathway.

Ligand Defect-Induced Active Sites in Ni-MOF-74 for Efficient Photocatalytic CO2 Reduction to CO.

The conversion of CO2 into valuable carbon-based products using clean and renewable solar energy has been a significant challenge in photocatalysis. It is of paramount importance to develop efficient photocatalysts for the catalytic conversion of CO2 using visible light. In this study, the Ni-MOF-74 material is successfully modified to achieve a highly porous structure (Ni-74-Am) through temperature and solvent modulation. Compared to the original Ni-MOF-74, Ni-74-Am contains more unsaturated Ni active sites resulting from defects, thereby enhancing the performance of CO2 photocatalytic conversion. Remarkably, Ni-74-Am exhibits outstanding photocatalytic performance, with a CO generation rate of 1380 µmol g-1 h-1 and 94% CO selectivity under visible light, significantly surpassing the majority of MOF-based photocatalysts reported to date. Furthermore, experimental characterizations reveal that Ni-74-Am has significantly higher efficiency of photogenerated electron-hole separation and faster carrier migration rate for photocatalytic CO2 reduction. This work enriches the design and application of defective MOFs and provides new insights into the design of MOF-based photocatalysts for renewable energy and environmental sustainability. The findings of this study hold significant promise for developing efficient photocatalysts for CO2 reduction under visible-light conditions.

Modulating the Moderate d-Band Center of Indium in InVO4 Nanobelts by Synergizing MnOx and Oxygen Vacancies for High-Efficiency CO2 Photoreduction.

Modulating the electronic properties of transition metal sites in photocatalysts at the atomic level is essential for achieving high-activity carbon dioxide photoreduction (CO2PR). An electronic strategy is herein proposed to engineer In-d-band center of InVO4 by incorporating MnOx nanoparticles and oxygen vacancies (VO) into holey InVO4 nanobelts (MnOx/VO-InVO4), which synergistically modulates the In-d-band center to a moderate level and consequently leads to high-efficiency CO2PR. The MnOx/VO-InVO4 catalyst with optimized electronic property exhibits a single carbon evolution rate of up to 145.3 µmol g-1 h-1 and a carbon monoxide (CO) product selectivity of 92.6%, coming out in front of reported InVO4-based materials. It is discovered that the modulated electronic property favors the interaction between the In sites and their intermediates, which thereby improves the thermodynamics and kinetics of the CO2PR-to-CO reaction. This work not only demonstrates the effective engineering of the d orbital of the low-coordination In atoms to promote CO2PR, but also paves the way for the application of tuning d-band center to develop high-efficiency catalysts.

A Novel Non-Fullerene D-A Interface with Two Asymmetrical Electron Acceptors Facilitates Charge and Energy Transfer for Effective Carbon Dioxide Reduction.

Converting carbon dioxide (CO2) into high-value chemicals using solar energy remains a formidable challenge. In this study, the CSC@PM6:IDT6CN-M:IDT8CN-M non-fullerene small-molecule organic semiconductor is designed with highly efficient electron donor-acceptor (D-A) interface for photocatalytic reduction of CO2. Atomic Force Microscope and Transmission Electron Microscope images confirmed the formation of an interpenetrating fibrillar network after combination of donor and acceptor. The CO yield from the CSC@PM6:IDT6CN-M:IDT8CN-M reached 1346 µmol g-1 h-1, surpassing those of numerous reported inorganic photocatalysts. The D-A structure effectively facilitated charge separation to enable electrons transfer from the PM6 to IDT6CN-M:IDT8CN-M. Meanwhile, attributing to the dipole moments of the strong intermolecular interactions between IDT6CN-M and IDT8CN-M, the intermolecular forces are enhanced, and laminar stacking and π-π stacking are strengthened, thereby reinforcing energy transfer between acceptor molecules and significantly enhanced charge separation. Moreover, the strong internal electric field in the D-A interface enhanced the excited state lifetime of PM6:IDT6CN-M:IDT8CN-M. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis demonstrated that carboxylate (COOH*) is the predominant intermediate during CO2 reduction, and possible pathways of CO2 reduction to CO are deduced. This study presents a novel approach for designing materials with D-A interface to achieve high photocatalytic activity.

Enhanced Solar Fuel Production over In2 O3 @Co2 VO4 Hierarchical Nanofibers with S-Scheme Charge Separation Mechanism.

The conversion of CO2 into valuable solar fuels via photocatalysis is a promising strategy for addressing energy shortages and environmental crises. Here, novel In2 O3 @Co2 VO4 hierarchical heterostructures are fabricated by in situ growing Co2 VO4 nanorods onto In2 O3 nanofibers. First-principle calculations and X-ray photoelectron spectroscopy (XPS) measurements reveal the electron transfer between In2 O3 and Co2 VO4 driven by the difference in work functions, thus creating an interfacial electric field and bending the bands at the interfaces. In this case, the photogenerated electrons in In2 O3 transport to Co2 VO4 and recombine with its holes, indicating the formation of In2 O3 @Co2 VO4 S-scheme heterojunctions and resulting in effective separation of charge carriers, as confirmed by in situ irradiation XPS. The unique S-scheme mechanism, along with the enhanced optical absorption and the lower Gibbs free energy change for the production of * CHO, significantly contributes to the efficient CO2 photoreduction into CO and CH4 in the absence of any molecule cocatalyst or scavenger. Density functional theory simulation and in situ diffuse reflectance infrared Fourier transform spectroscopy are employed to elucidate the reaction mechanism in detail.

Nanostructurally Engineering Covalent Organic Frameworks for Boosting CO2 Photoreduction.

Herein, a series of imine-linked covalent organic frameworks (COFs) are developed with advanced ordered mesoporous hollow spherical nanomorphology and ultra-large mesopores (4.6 nm in size), named OMHS-COF-M (M = H, Co, and Ni). The ordered mesoporous hollow spherical nanomorphology is revealed to be formed via an Ostwald ripening mechanism based on a one-step self-templated strategy. Encouraged by its unique structural features and outstanding photoelectrical property, the OMHS-COF-Co material is applied as the photocatalyst for CO2-to-CO reduction. Remarkably, it delivers an impressive CO production rate as high as 15 874 µmol g-1 h-1, a large selectivity of 92.4%, and a preeminent cycling stability. From in/ex situ experiments and density functional theory (DFT) calculations, the excellent CO2 photoreduction performance is ascribed to the desirable cooperation of unique ordered mesoporous hollow spherical host and abundant isolated Co active sites, enhancing CO2 activation, and improving electron transfer kinetics as well as reducing the energy barriers for intermediates *COOH generation and CO desorption.

Amorphous Strategy and Doping Copper on Metal-organic Framework Surface for Enhanced Photocatalytic CO2 Reduction to C2H4.

Amorphous photocatalysts are characterized by numerous grain boundaries and abundant unsaturated sites, which enhance reaction efficiency from both kinetic and thermodynamic perspectives. However, amorphization strategies have rarely been used for photocatalytic CO2 reduction. Doping copper onto a metal-organic framework (MOF) surface can regulate the electronic structure of photocatalysts, promote electron transfer from the MOF to Cu, and improve the separation efficiency of electron-hole pairs. In this study, an amorphous photocatalyst MOFw-p/Cu containing highly dispersed Cu (0, I, II) sites was designed and synthesized by introducing a regulator and in situ copper species during the nucleation process of MOF (UiO-66-NH2). Various characterizations confirmed that the Cu species were anchored to the organometallic skeleton of the surface amorphization MOF structure. The synergistic effect of Cu doping and surface amorphization in MOFw-p/Cu can significantly enhance the CO and CH4 yields while promoting the formation of the multicarbon product C2H4. The approach holds promise for developing novel, highly efficient MOFs as photocatalysts for CO2 photoreduction, enabling the production of high-value-added C2 products.

Selective CO2 Photoreduction Enabled by Water-stable Cu-based Metal-organic Framework Nanoribbons.

The goal of photocatalytic CO2 reduction system is to achieve near 100 % selectivity for the desirable product with reasonably high yield and stability. Here, two-dimensional metal-organic frameworks are constructed with abundant and uniform monometallic active sites, aiming to be an emerged platform for efficient and selective CO2 reduction. As an example, water-stable Cu-based metal-organic framework nanoribbons with coordinatively unsaturated single CuII sites are first fabricated, evidenced by X-ray diffraction patterns and X-ray absorption spectroscopy. In situ Fourier-transform infrared spectra and Gibbs free energy calculations unravel the formation of the key intermediate COOH* and CO* is an exothermic and spontaneous process, whereas the competitive hydrogen evolution reaction is endothermic and non-spontaneous, which accounts for the selective CO2 reduction. As a result, in an aqueous solution containing 1 mol L-1 KHCO3 and without any sacrifice reagent, the water-stable Cu-based metal-organic framework nanoribbons exhibited an average CO yield of 82 µmol g-1 h-1 with the selectivity up to 97 % during 72 h cycling test, which is comparable to other reported photocatalysts under similar conditions.

Minimizing CO2 emissions by photocatalytic CO2 reduction to CH3OH over Li2MnO3/WO3 heterostructures under visible illumination.

Photocatalytic CO2 reduction to valuable fuels has proved to be a favourable process to produce renewable energy and reduce CO2 emissions, which mostly depends on designing effective photocatalysts with the rapid separation rate of charge carriers. In this contribution, mesoporous n-n heterojunction Li2MnO3/WO3 nanocomposites were designed via a simplistic sol-gel process for CO2 reduction utilizing visible illumination (λ > 420 nm). XRD and TEM measurements confirmed the synthesized Li2MnO3/WO3 nanocomposite is a monoclinic structure, and its particle size is 25 ± 5 nm. The obtained Li2MnO3/WO3 exhibited narrower bandgap energy (1.74 eV), larger surface area (212 m2g-1), exceedingly visible absorbing, and lower recombination of electron and hole. The yield of CH3OH was determined about 198, 871, 1140, 1550 and 1570 mmolg-1 for bare WO3 and 5%, 10%, 15% and 20% Li2MnO3/WO3 nanocomposites, respectively. These results evidenced that the 15% Li2MnO3/WO3 photocatalyst exhibited the best reduction ability compared to other nanocomposites. The CO2 reduction over 15% Li2MnO3/WO3 photocatalyst achieved a maximal CO2 conversion with the substantially boosted CH3OH, i.e., 1550 mmolg-1 after 9 h, which was enhanced 7.8 folds great than of WO3 NPs. Mesoporous Li2MnO3/WO3 nanocomposites, in comparison with bare WO3 NPs, created more active sites for facilitating CO2 and had a specific electric field to more effectively separate charge carriers. The Li2MnO3/WO3 photocatalyst has superior photostability during the continuous reduction of CO2 for 45 h with no remarkable decrease. The possible direct S-scheme mechanism for electron transfer over Li2MnO3/WO3 photocatalyst with the enhanced CO2 reduction ability was discussed. The present work demonstrates an avenue for building highly effective heterostructure photocatalysts in solar-energy-induced potential applications.

Photoactivity of amorphous and crystalline TiO2 nanotube arrays (TNA) films in gas phase CO2 reduction to methane with simultaneous H2 production.

This study assessed the photoactivity of amorphous and crystalline TiO2 nanotube arrays (TNA) films in gas phase CO2 reduction. The TNA photocatalysts were fabricated by titanium anodization and submitted to an annealing treatment for crystallization and/or cathodic reduction to introduce Ti3+ and oxygen vacancies into the TiO2 structure. The cathodic reduction demonstrated a significant effect on the generated photocurrent. The photoactivity of the four TNA catalysts in CO2 reduction with water vapor was evaluated under UV irradiation for 3 h, where CH4 and H2 were detected as products. The annealed sample exhibited the best performance towards methane with a production rate of 78 µmol gcat-1 h-1, followed by the amorphous film, which also exhibited an impressive formation rate of 64 µmol gcat-1 h-1. The amorphous and reduced-amorphous films exhibited outstanding photoactivity regarding H2 production (142 and 144 µmol gcat-1 h-1, respectively). The annealed catalyst also revealed a good performance for H2 production (132 µmol gcat-1 h-1) and high stability up to five reaction cycles. Molecular dynamic simulations demonstrated the changes in the band structure by introducing oxygen vacancies. The topics covered in this study contribute to the Sustainable Development Goals (SDG), involving affordable and clean energy (SDG#7) and industry, innovation, and infrastructure (SDG#9).

Amorphization-Induced Cation Exchange in Indium Oxide Nanosheets for CO2-to-Ethanol Conversion.

Cation exchange (CE) in metal oxides under mild conditions remains an imperative yet challenging goal to tailor their composition and enable practical applications. Herein, we first develop an amorphization-induced strategy to achieve room-temperature CE for universally synthesizing single-atom doped In2O3 nanosheets (NSs). Density functional theory (DFT) calculations elucidate that the abundant coordination-unsaturated sites present in a-In2O3 NSs are instrumental in surmounting the energy barriers of CE reactions. Empirically, a-In2O3 NSs as the host materials successfully undergo exchange with unary cations (Cu2+, Co2+, Mn2+, Ni2+), binary cations (Co2+Mn2+, Co2+Ni2+, Mn2+Ni2+), and ternary cations (Co2+Mn2+Ni2+). Impressively, high-loading single-atom doped (over 10 atom %) In2O3 NSs were obtained. Additionally, Cu/a-In2O3 NSs exhibit an excellent ethanol yield (798.7 µmol g-1 h-1) with a high selectivity of 99.5% for the CO2 photoreduction. This work offers a new approach to induce CE reactions in metal oxides under mild conditions and constructs scalable single-atom doped catalysts for critical applications.

Synergistic Enhancement of CO2 photoreduction through sulfur defects in (3D/2D) CdS-nanoflowers/CN Binary heterojunction photocatalyst under visible light.

Global warming is the biggest threat to the entire world owing to the continuous release of greenhouse gases such as CO2 from various sources. Herein, we have utilized renewable energy for the conversion of CO2 to valuable feedstocks through a semiconductor-mediated photocatalytic system. The cadmium sulfide nanoflowers (CS-NFs) decorated graphitic carbon nitride (CN) through a solvothermal route to form a Z-scheme CSCN heterojunction. The as-synthesized material has been characterized by various spectroscopic and microscopic tools. The optimal CSCN-0.5 (1:0.5) photocatalyst achieves a CO production rate of 130.9 µmol g-1 under visible light irradiation of 4h (λ > 420 nm), doubling that of pristine CS-NFs and CN. CO, along with CH4 (3.4 µmol g-1) and C2H6 (2.9 µmol g-1), is the sole product detected. Experimental results indicate that the CSCN-0.5 photocatalyst spatially separates electron-hole pairs, suppresses charge carrier recombination, and maintains robust redox ability, enhancing CO2 photoreduction. The CO2 reduction mechanism over CSCN heterojunction was also studied through in-situ DRIFTS and electron spin resonance (ESR) measurements. Therefore, CSCN proves that it could be used as a robust photocatalyst for the CO2 reduction reactions towards C1 and C2 feedstocks.

Enhancing d/p-2π* Orbitals Hybridization via Strain Engineering for Efficient Photoreduction CO2.

The photoconversion of CO2 into valuable chemical products using solar energy is a promising strategy to address both energy and environmental challenges. However, the strongly adsorbed CO2 frequently impedes the seamless advancement of the subsequent reaction by significantly increasing the reaction activation energy. Here, we present a BiFeO3 material with lattice strain that collaboratively regulates the d/p-2π* orbitals hybridization between metal sites and *CO2 as well as *COOH intermediates to achieve rapid conversion of solidly adsorbed CO2 to critical *COOH intermediates, accelerating the overall CO2 reduction kinetics. Quasi in-situ X-ray photoelectron spectroscopy and in-situ Fourier Transform infrared spectroscopy combined with theoretical calculation reveals that the optimized Fe sites enhance the adsorption and activation effect of CO2, and continuous internal electrons are rapidly transferred to the reaction sites and injected into the surface *CO2 and *COOH under the condition of illumination, which promotes the rapid formation and stability of *COOH. Certainly, the performance of CO2 photoreduction to CO is improved by 12.81-fold compared with the base material. This work offers a new perspective for the rapid photoreduction process of strongly adsorbed CO2.

Clustering-Resistant Cu Single Atoms on Porous Au Nanoparticles Supported by TiO2 for Sustainable Photoconversion of CO2 into CH4.

Photocatalysts based on single atoms (SAs) modification can lead to unprecedented reactivity with recent advances. However, the deactivation of SAs-modified photocatalysts remains a critical challenge in the field of photocatalytic CO2 reduction. In this study, we unveil the detrimental effect of CO intermediates on Cu single atoms (Cu-SAs) during photocatalytic CO2 reduction, leading to clustering and deactivation on TiO2. To address this, we developed a novel Cu-SAs anchored on Au porous nanoparticles (CuAu-SAPNPs-TiO2) via a vectored etching approach. This system not only enhances CH4 production with a rate of 748.8 µmol ⋅ g-1 ⋅ h-1 and 93.1 % selectivity but also mitigates Cu-SAs clustering, maintaining stability over 7 days. This sustained high performance, despite the exceptionally high efficiency and selectivity in CH4 production, highlights the CuAu-SAPNPs-TiO2 overarching superior photocatalytic properties. Consequently, this work underscores the potential of tailored SAs-based systems for efficient and durable CO2 reduction by reshaping surface adsorption dynamics and optimizing the thermodynamic behavior of the SAs.