An integrated approach to construct tantalum derivatives for electrocatalysis beyond the triiodide reduction reaction

Abstract

The counter electrode (CE) is an essential component in dye-sensitized solar cells (DSSCs) to transfer electrons and catalyze triiodide reduction. In this research, efficient and cost-effective tantalum derivatives (oxide, nitride, carbide, oxynitride, and corresponding hybrids) are synthesized and utilized as CEs in DSSCs toward the triiodide reduction. The DSSC with mixed-anionic TaON CE achieves a cell efficiency of 5.46%, surpassing that with pristine TaOx CE (5.20%) before nitriding treatment. Benefiting from the synergistic interaction between mesoporous carbon (MC) and TaC0.95, TaC0.95/MC hybrid CE-based DSSC possess superior cell efficiency of 7.23%, higher than that of respective TaC (6.24%) and MC (6.52%), especially standard Pt (6.34%). Furthermore, TaON and TaC0.95/MC CEs exhibit durably great catalytic activity for I3- reduction. This work raises an effective and generally accepted approach to construct transition metal derivatives, which could utilize as low-priced Pt-free electrocatalysts for new energy devices.