Improved hydrogen generation integrated with methanol electrooxidation by manganese selenide/cobalt selenide heterostructure electrocatalyst

Abstract

The electro-oxidation of mono-alcohol molecules to produce valuable products in combination with the formation of hydrogen is not an easy process. Herein, the manganese selenide/cobalt selenide hetero-nanoparticles embedded in nitrogen-doped carbon (namely MnSe/Co0.85Se@NC) are fabricated as high-performance catalysts by regulating electronic structures through heterointerface engineering. Experimental and theoretical results demonstrate that the formation of MnSe/Co0.85Se heterostructure will take charges from the Co0.85Se sites, which is advantageous to the adsorption of mono-alcohol molecules and thus makes Co0.85Se a high-performance electrocatalyst for mono-alcohol oxidation reactions (M−AOR). Notably, the activity order of M−AOR on the MnSe/Co0.85Se@NC electrode is methanol > ethanol > n-propanol > isopropanol. Furthermore, the charge transfer from Co0.85Se to MnSe occurs, resulting in a strong electronic interaction at the heterointerface of MnSe/Co0.85Se, giving it superior HER activity. Impressively, MnSe/Co0.85Se@NC can be used as a bifunctional catalyst for methanol-assisted water electrolysis in a two-electrode configuration, which only demands a cell potential of 1.49 V to obtain the 10 mA cm−2 current density, accompanying with valuable formate generation at the anode and hydrogen generation at the cathode. This tactic employing a heterogeneous electrocatalyst to produce high-value chemicals is considered of great importance in the development of new energy technology.