Competent overall water-splitting electrocatalysts derived from ZIF-67 grown on carbon cloth

Abstract

The design of nonprecious, bifunctional, and highly competent electrocatalysts for both H₂ and O₂ evolution reactions (HER and OER) has attracted increasing interest recently. Herein, we report a cobalt-based electrocatalyst derived from ZIF-67 grown on carbon cloth (Co–P/NC/CC) for overall water splitting electrocatalysis. The as-prepared Co–P/NC/CC catalyst exhibited remarkable catalytic performance in 1 M KOH with Tafel slopes of 52 and 61 mV dec⁻¹ for HER and OER, respectively. When serving as catalysts for both the cathode and anode, our Co–P/NC/CC demonstrated high efficiency and strong robustness. A thorough comparison with other control samples and detailed characterization results revealed that the superior activity and excellent stability of Co–N–C likely originated from the highly porous, self-supported, and binder-free nature of the electrocatalyst, as well as the high conductivity of carbon cloth. Hence, direct decoration of metal organic frameworks on conductive substrates represents an effective approach for the development of electrocatalysts not only promising for water splitting but also for many other applications.