Zn−Co−S Colloidal Nanocrystal Clusters as Efficient and Durable Bifunctional Electrocatalysts For Full Water Splitting

Abstract

The synthesis of efficient, cost‐effective, and non‐toxic bifunctional electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is highly needed for renewable energy related processes (conversion and storage). In the present work, we report a simple and straightforward one‐step hydrothermal strategy to prepare Zn−Co−S colloidal nanocrystal clusters (CNCs) for total water splitting (OER and HER activity) for the first time. The Zn−Co−S CNCs consist of a large number of interconnected nanoparticles forming spherical structures, which is very helpful for the electrochemical activity. Under alkaline conditions, the Zn−Co−S electrocatalyst demonstrates an excellent electrocatalytic activity by driving 10 mA cm−2 at 157 mV HER and 320 mV OER overpotentials, respectively. The Zn−Co−S catalyst electrode maintained the catalytic activity for 12 h exhibiting a good electrochemical stability. Furthermore, as fabricated two‐electrode alkaline water‐splitting system of Zn−Co−S//Zn−Co−S affords 10 mA cm−2 at a voltage of 1.64 V.

One-step synthesis of mesoporous Cobalt sulfides (CoSx) on the metal substrate as an efficient bifunctional electrode for overall water splitting

“…6a compared the electrocatalytic performance (η10) of some latest reported cobalt-based compounds as bifunctional catalysts for overall water splitting. [5,6,9,19,37,[50][51][52][53][54][55][56][57][58][59] In the figure, these bifunctional catalysts were roughly separated into four different groups according to their sum overpotential value (η10 S ) of HER and OER (η10 S = η10 HER + η10 OER ). The catalysts with a η10 S value below 300 mV were in group I, indicating both fantastic HER and OER performance.…”

Controlling incorporation of TiO2 nanoparticles in the carbonization process: a new strategy to develop a nitrogen-doped carbon-based Mo2C@TiO2 electrocatalyst for electrochemical hydrogen evolution reaction

“…Recently, transition metal-based electrocatalysts have shown outstanding activity to catalyze the HER, such as metal oxides and hydroxides, metal nitrides, metal chalcogenides and metal carbides, 11–23 etc. Among them, molybdenum carbide has been given more attention for the HER process, because of the Pt-like surface electronic structure of Mo 2 C. 24 But the electrocatalytic performance of Mo 2 C is highly dependent on the morphology, crystal structure and conductive support.…”

Spatial Compartmentalization of Cobalt Phosphide in P-Doped Dual Carbon Shells for Efficient Alkaline Overall Water Splitting

“…Among various nonprecious metal-based electrocatalysts such as metal oxides, chalcogenides. − carbides, and phosphides. − TMPs have become a hot spot for overall water splitting due to their hydrogenase-like properties. As known, phosphors atoms with more electronegativity as proton carriers can easily capture protons onto the surface of the catalyst and transfer the electrons from metal sites to the P sites, boosting the HER performance, while forming peroxide intermediate to improve the OER activities .…”