Electrocatalytic reduction of carbon dioxide into value-added
chemical
fuels is a promising way to achieve carbon neutrality. Bismuth-based
materials have been considered as favorable electrocatalysts for converting
carbon dioxide to formic acid. Moreover, size-dependent catalysis
offers significant advantages in catalyzed heterogeneous chemical
processes. However, the size effects of bismuth nanoparticles on formic
acid production have not been fully explored. Here, we prepared Bi
nanoparticles uniformly supported on porous TiO2substrate
electrocatalytic materials by in situ segregation of the Bi element
from Bi4Ti3O12. The Bi-TiO2electrocatalyst with Bi nanoparticles of 2.83 nm displays a Faradaic
efficiency of greater than 90% over a wide potential range of 400
mV. Theoretical calculations have also demonstrated subtle electronic
structural evolutions induced by the size variations of Bi nanoparticles,
where the 2.83 nm Bi nanoparticles display the most active p-band
and d-band centers to guarantee high electroactivity toward CO2RR.