Key points are not available for this paper at this time.
Photoelectrochemical (PEC) cells have been extensively studied in water splitting to produce H2, but the sluggish kinetics of the oxygen evolution reaction (OER) remains a huge challenge. Here, we reported a PEC strategy for biomass-derived succinic acid decarboxylation to replace OER, with the production of ethylene (C2H4) as a high-demand chemical. By synthesizing a bismuth oxide supported on titanium oxide (BiOx/TiO2) as the photoanode, C2H4 was efficiently produced with 85.7 μmol/h production rate and 40% Faradaic efficiency. Simultaneously, H2 productivity was improved by 6.5-fold compared with total water splitting (from 50.8 to 331.7 μmol/h). Structure characterizations show that BiOx forms an ultrathin layer (approximately 1.5 nm in thickness) on the TiO2 surface with a strong interfacial interaction, inducing the formation of a type-II heterojunction with efficient charge separation and transfer. Experimental data suggest that succinic acid molecules are adsorbed over the BiOx surface with its dual carboxyl groups in a deprotonated form, facilitating the decarboxylation of succinic acid to ethylene via a non-Kolbe route. This work demonstrates the great opportunity of PEC technology for transforming renewable biomass resources into value-added chemicals with promoted H2 fuel production under mild conditions.
Shi et al. (Wed,) studied this question.