Ultrafast electron transfer at the In ₂O ₃/Nb ₂O ₅ S-scheme interface for CO ₂ photoreduction

Abstract

Constructing S-scheme heterojunctions proves proficient in achieving the spatial separation of potent photogenerated charge carriers for their participation in photoreactions. Nonetheless, the restricted contact areas between two phases within S-scheme heterostructures lead to inefficient interfacial charge transport, resulting in low photocatalytic efficiency from a kinetic perspective. Here, In ₂O ₃/Nb ₂O ₅ S-scheme heterojunctions are fabricated through a straightforward one-step electrospinning technique, enabling intimate contact between the two phases and thereby fostering ultrafast interfacial electron transfer (<10 ps), as analyzed via femtosecond transient absorption spectroscopy. As a result, powerful photo-electrons and holes accumulate in the Nb ₂O ₅ conduction band and In ₂O ₃ valence band, respectively, exhibiting extended long lifetimes and facilitating their involvement in subsequent photoreactions. Combined with the efficient chemisorption and activation of stable CO ₂ on the Nb ₂O ₅, the resulting In ₂O ₃/Nb ₂O ₅ hybrid nanofibers demonstrate improved photocatalytic performance for CO ₂ conversion.

Abstract

In ₂O ₃/Nb ₂O ₅ S-scheme heterojunctions fabricated via a one-step electrospinning technique facilitate contact between two phases, fostering ultrafast interfacial electron transfer to prolong lifetimes and improve CO ₂ photoreduction performance.