Engineering a defect-rich high entropy oxides/carbon composites by soybean polysaccharide template for hydrogen...

Optimizing the configurational entropy of the electrocatalyst is one of a powerful strategy to improve the performance. The high-entropy oxide has multiple active sites and lattice distortion, which is a promising candidate for promoting hydrogen evolution. In this work, FeCoNiZnMgO_x/carbon (HEO/C) composite is synthesized using soybean polysaccharide as a template. The polysaccharide template gives HEO/C a nanoparticle morphology and facilitates the generation of oxygen vacancies, which are important for fine-adjusting of its electronic structure. Hence, the optimized HEO/C composite catalyst exhibited excellent electrocatalytic hydrogen evolution performance, achieving 10 mA cm^-2 with a mere 46 mV overpotential, along with a Tafel slope of 74.0 mV dec^-1. The excellent electrocatalytic process and simple production technology of oxygen vacancy-rich high-entropy oxides/carbon provide a feasible pathway toward advanced high-property electrocatalysts.