Deep interface engineering of coupled perovskite solar cells and CO2 electrocatalytic conversion: Construction and application of a high-performance photo-electro-catalytic integrated platform

A deeply integrated photo-electro-catalytic platform couples a high-efficiency perovskite solar cell (PSC) with a CO 2 electrocatalytic conversion unit via precision dual-interface engineering. Incorporation of Li+ -doped SnO 2 in the electron-transport layer and a MoOₓ-modified Spiro-OMeTAD hole-transport layer raises power conversion efficiency from 16.8 % to 21.7 % by reducing interfacial recombination (charge-transfer resistance decreases by 45 %, carrier lifetime increases by 32 %). A low-impedance conductive scaffold and porous separator enable a stable 1.12 V output that directly drives CO 2 reduction. Under simulated aqueous CO 2 conditions, the peak reduction rate reaches 4.86 µmol cm −2 h −1 (Faradaic efficiency: CO 82 %, HCOO⁻ 10 %, CH 4 2 %) with an overall solar-to-chemical efficiency of 15.3 % and simultaneous removal of > 93 % NOₓ/SOₓ pollutants. Long-term tests (500 h simulated, 100 h real flue gas) demonstrate > 85 % PCE retention and 88 % pollutant removal, with negligible catalyst deactivation or product crossover. Cradle-to-grave life-cycle assessment reveals ∼ 40 % lower CO 2 -equivalent emissions and energy return on investment > 1.8 compared to grid-powered electrocatalysis. Module-level roll-to-roll fabrication (100 m 2 h −1 ) and > 90 % Pb recovery underscore scalability and environmental viability. A unified strategy of interface and active-site engineering establishes a robust, modular route for scalable deployment of perovskite-based photo-electro-catalytic technologies in sustainable CO 2 valorization and environmental remediation. • Developed a dual-interface engineering strategy combining Li⁺-doped SnO₂ and MoOₓ-modified Spiro-OMeTAD to synergistically suppress interfacial recombination, passivate defects, and optimize energy alignment, enabling efficient carrier extraction and enhanced device stability. • Established an integrated photo-electro-catalytic platform and demonstrated, under realistic NOₓ/SOₓ-containing flue gas conditions, that the interface architecture shields acid corrosion, achieving > 100 h of sustained operation. • Designed a cascade downstream integration pathway coupling electrochemical products (CO/HCOO⁻/H₂) with microbial biotransformation, boosting overall carbon utilization efficiency without degrading photovoltaic performance. • Proposed a scalable modular deployment (30 cm × 30 cm units) with roll-to-roll–compatible interface/catalyst fabrication and provided preliminary cost benchmarking, illustrating practical integration into industrial exhaust treatment. • Validated performance gains through multi-batch statistical analysis, light-intensity stress testing, and Ag–Cu bimetallic vs. monometallic benchmarking to clarify the interfacial and catalytic synergy driving selectivity, efficiency, and reproducibility.