Correct determination of the hydrogen evolution reaction parameters at Ni foam electrode modified by electrodeposited Ni-Sn alloy layer

Abstract

The example of the procedure for the correct determination of the parameters of hydrogen evolution reaction (HER), the exchange current density (jo) and relaxation time (τo) for intermediate (adsorbed hydrogen, Hads) adsorption at modified porous Ni-based electrode are presented in this work. Such a procedure is applicable for the HER at all electrode materials. The value of jo was obtained from the intercept at η = 0 mV from the η vs. log (Rct-1) dependence (η-overpotential), while the value of τo was obtained from the intercept at η = 0 mV from the logτ vs. η dependence. It was shown that for the correct determination of jo and τo, it is necessary to correct applied η for the jRs drop, by recording current density (j) for applied η and correcting it for jRs.

Na primeru izdvajanja vodonika na Ni-Sn/Ni pena 800 elektrodi u ovom radu je prikazana procedura korektnog određivanja parametara ove reakcije, a to su: gustina struje izmene (jo) i relaksaciono vreme adsorpcije intermedijara () (Hads). Vrednost jo je određena iz odsečka za  = 0 mV zavisnosti  vs. log(Rct-1 ) ( - prenapetost), dok je vrednost o određena iz odsečka za  = 0 mV zavisnosti log vs. . Pokazano je da je za korektno određivanje ovih parametara neophodno korigovati gustinu struje pri svakoj zadatoj prenapetosti za vrednost omskog pada napona jRs.