Ni-O-Ag catalyst enables 103-m$^2$ artificial photosynthesis with >16% solar-to-chemical energy conversion efficiency

TL;DR

This paper reports a novel Ni-O-Ag catalyst enabling large-scale artificial photosynthesis with over 16% solar-to-chemical energy conversion efficiency, significantly advancing sustainable solar fuel production.

Contribution

The study introduces a NiO nanosheet supported with Ag single atoms that achieves unprecedented low-light CO2 hydrogenation performance and integrates into a scalable artificial photosynthesis system.

Findings

Achieved 1065 mmol g$^{-1}$ h$^{-1}$ CO production under 1 sun.

Surpassed previous low-temperature RWGS performance.

Realized a 103 m$^2$ scale artificial photosynthesis system with >16% efficiency.

Abstract

Herein, NiO nanosheets supported with Ag single atoms are synthesized for photothermal CO2 hydrogenation to achieve 1065 mmol g$^{-1}$ h$^{-1}$ of CO production rate under 1 sun irradiation, revealing the unparalleled weak sunlight driven reverse water-gas shift reaction (RWGS) activity. This performance is attributed to the coupling effect of Ag-O-Ni sites to enhance the hydrogenation of CO$_2$ and weaken the CO adsorption, resulting in 1434 mmol g$^{-1}$ h$^{-1}$ of CO yield at 300$^\circ$ C, surpassing any low-temperature RWGS performances ever reported. Building on this, we integrated the 2D Ni$_1$Ag$_{0.02}$O$_1$ supported photothermal RWGS with commercial photovoltaic electrolytic water splitting, leading to the realization of 103 m$^2$ scale artificial photosynthesis system (CO$_2$+H$_2$$\to$CO+H$_2$O) with a daily CO yield of 18.70 m$^3$, a photochemical energy conversion efficiency of >16%, over 90% H$_2$ ultilization efficiency, outperforming other types of artificial photosynthesis. The results of this research chart a promising course for designing practical, natural sunlight-driven artificial photosynthesis systems and highly efficient platinum-free CO$_2$ hydrogenation catalysts. This work is a significant step towards harnessing solar energy more efficiently and sustainably, opening exciting possibilities for future research and development in this area.