Computational Design of Optimized Modular Photovoltaic Electrochemical Reactor for Energy Efficient CO2‐to‐Cn Reduction Reaction with Bandgap Tunable Perovskite Tandem Cells

Abstract

AbstractFor electrosynthesis of carbon fuels from CO2, engineered catalysts have improved the electrochemical (EC) reduction efficiency. However, most EC systems rely on a batch reactor, which is not relevant for Cn fuels with high n (n ≥ 3) due to low selectivity. For enhanced electron‐to‐fuel (ETF) efficiency, modular configurations are advantageous. The best configurations allowing high yield reduction of CO2 into Cn fuels are investigated. It is found that serial and parallel configurations exhibit four to five times higher ETF efficiency than simple batch reactor. The best photovoltaic (PV) tandem cells made of metal halide perovskite for the optimized EC modular systems are also found. These materials have a bandgap tunability covering most Cn fuels. With the computationally optimized tandem PVs, it is found that the [PV+EC] series configuration achieves up to 2.28% and 2.86% solar‐to‐fuel (STF) efficiency of C3 aldehydes and alcohols, which are greater than what has been reported in the literature. For C4 aldehydes and alcohols, the [PV+EC] parallel configuration achieves up to 0.17% and 0.21% STF efficiency, respectively. The present study on modules and materials design will provide a useful way to create EC production of Cn fuels that can help reach carbon neutrality.