Accelerating photoelectric CO2 conversion with a photothermal wavelength-dependent plasmonic local field

The fabrication of an efficient and low-cost photocathode still remains a big challenge. We herein report a Ag/Cux[email protected]/Mo photocathode for CO2 conversion. A unique wavelength-dependent performance is found to enhance the formation of the key intermediate groups by exciting photothermal local surface plasmonic resonance (LSPR) using the lights with wavelengths ranging from 550 to 600 nm. CO, H2 and CH4 can be stably produced with dual photoelectrodes using a neutral solution. An unbiased solar-to-gaseous-carbon-fuel efficiency (SGCF) of 0.51 % has been achieved, which sets a record for carbon gas fuel production with binary photoelectrodes. In addition, the CO/H2 ratio could be tuned in the range from 0.65 to 1.84, which makes it possible to fine tune the syngas production. The excellent PEC CO2 reduction capability achieved by the new wavelength-dependent catalytic route may shine some lights for the future design and development of the next-generation PEC materials and devices.