Electroless Plating of Highly Efficient Bifunctional Boride-Based Electrodes toward Practical Overall Water Splitting

Exploring highly-efficient and low-cost electrodes for both hydrogen and oxygen evolution reaction (HER and OER) is of primary importance to economical water splitting. Herein, a series of novel and robust bifunctional boride-based electrodes are successfully fabricated using a versatile Et2NHBH3-involved electroless plating (EP) approach via deposition of nonprecious boride-based catalysts on various substrates. Owing to the unique binder-free porous nodule structure induced by the hydrogen release EP reaction, most of the nonprecious boride-based electrodes are highly efficient for overall water splitting. As a distinctive example, the Co-B/Ni electrode can afford 10 mA cm(-2) at overpotentials of only 70 mV for HER and 140 mV for OER, and can also survive at large current density of 1000 mA cm(-2) for over 20 h without performance degradation in 1.0 (M) KOH. Several boride-based two-electrode electrolyzers can achieve 10 mA cm(-2) at low voltages of around 1.4 V. Moreover, the facile EP approach is economically viable for flexible and large size electrode production.