Higher Water-Splitting Performance of Boron-Based Porous CoMnB Electrocatalyst over the Benchmarks at High Current in 1 M KOH and Real Sea Water

The development of highly efficient and stable electrocatalysts at an affordable cost is an essential component for the large-scale implementation of green hydrogen production. In this work, the fabrication of porous CoMnB electrocatalyst is demonstrated with the incorporation of boron into the Co-Mn matrix by an electrochemical approach for bifunctional water electrocatalysis for the first time. The optimized CoMnB electrocatalyst demonstrates an excellent bifunctionality with a low 2-E turnover voltage of 1.59 V at 20 mA cm(-2) in 1 M KOH. The CoMnB shows a comparable water-splitting current at low current range as compared with the standard benchmark electrodes of Pt/C parallel to RuO2 in 1 M KOH. Then, the CoMnB outperforms the benchmarks at above 800 mA cm(-2), indicating a better H-2 and O-2 generation performance at the industrial operational condition of high current range. The CoMnB also exhibits superior electrocatalytic activity in real sea water +1 m KOH. In addition, the porous CoMnB electrocatalyst exhibits an excellent stability with stable current for continuous 72 h operation at high current and excellent repeatability after 1000 cycles. The result ranks the CoMnB as one of the best transition metal-based water-splitting electrocatalysts at low cost with an easy fabrication approach.