Electrochemically Driven Interfacial Transformation For High-Performing Solar-To-Fuel Electrocatalytic Conversion

The carbon dioxide reduction reaction (CO2RR) suffers from poor selectivity with low Faradaic efficiency and limited current density due to the lack of advanced electrocatalysts. Herein, it is demonstrated that the electrochemically driven interfacial transformation of bismuth sulfide (Bi2S3) nanorods enables the in situ formation of a 3D bismuth nanosheet network (BiNN) on functionalized carbon fibers (BiNN-CFs). Notably, the formation of an ideal heterojunction with self-driven charge migration facilitates the composition conversion with rapid reduction of Bi2S3 nanorods in seconds. The functionalization of CFs via Joule heating of the polytetrafluoroethylene coating induces an interfacial interaction for the simultaneous morphology evolution into the hierarchical BiNN via the recrystallization process. More importantly, the hierarchical BiNN-CFs display improved performance for the CO2RR, including reasonable selectivity for formate generation (approximate to 92%) in the broad potential range, a large partial current density of 419 mA cm(-2), and good long-term stability. Theoretical understanding elucidates that the lattice distortion tunes the p-band center for optimizing the intermediate adsorption, and thus improving the electrocatalytic activity. Of particular note, the solar-driven CO2-H2O full cell also demonstrates a promising energy conversion efficiency of 13.3%. These advances demonstrate the large space to optimize electrocatalysis that stems from the rational regulation of interfacial structure and properties.

Automated summary

It has been demonstrated that the electrochemical transformation of bismuth sulfide nanorods can lead to the formation of a three-dimensional bismuth nanosheet network on functionalized carbon fibers, improving the performance of the carbon dioxide reduction reaction. The hierarchical bismuth nanosheet network shows high selectivity, large current density, and good long-term stability.