Improved alkaline hydrogen evolution performance of a Fe78Si9B13 metallic glass electrocatalyst by ultrasonic vibrations

The electrocatalytic performance of a Fe78Si9B13 amorphous alloy toward alkaline hydrogen evolution reaction (HER) is enhanced by ultrasonic vibration (UV). The UV treatments slightly increase the crystallization enthalpy of the Fe78Si9B13 amorphous alloy from 141.54 J/g to 145.32 J/g, meanwhile a large number of micro-cracks,-holes and-chips are generated on the surface of the amorphous alloy. The overpotentials of the amorphous alloy treated with ultrasonic energy of 5000 J is only 173 mV at 10 mA cm(-2) in 1.0 M KOH, which is reduced from 386 mV for the amorphous ribbon alloy at the same conditions. Moreover, the UV treated amorphous alloys also show better HER cycling performance comparing with those of the amorphous alloy without UV treatment. After 1000 CVs, it only needs 127 mV to reach the current density of 10 mA cm(-2) for the materials treated with 5000 J. After 1000 CVs cycling reaction, the UV treated amorphous alloy shows much enlarged specific area compared with that of the untreated amorphous alloy, which should be the reason for the improved cycling HER performance.