Quantum dot-doped CeO-NiB with modulated electron density as a highly efficient bifunctional electrocatalyst for water splitting.

Development of economical, efficient and durable non-noble metal electrocatalysts for the hydrogen/oxygen evolution reaction (HER/OER) holds great promise, but still faces great challenges. Herein, a strategy of doping metal borides with rare earth metal oxides and introducing silicon carbide (SiC) quantum dots has been explored to develop efficient bifunctional electrocatalysts. A novel electrocatalyst consists of SiC quantum dot-decorated CeO-NiB supported on nickel foam a one-step mild electroless plating reaction (denoted as CeO-NiB/SiC@NF). Notably, the modulated electron density of the CeO-NiB/SiC@NF electrode significantly boosts the electrochemically active surface area and electron transfer, and optimizes the hydrogen/water absorption free energy, which delivers current densities of 50 mA cm and 10 mA cm at overpotentials of only 131 mV and 234 mV for the HER and the OER, respectively. The target electrode requires only 1.43 V to provide 10 mA cm for overall water splitting in 1.0 M KOH. Moreover, the electrode also exhibits good stability and durability at the industrial-grade current density (0.5-1 A cm). This work provides a new idea for the development of efficient and durable non-precious metal catalysts.