Bio‐reduced <scp>GO</scp> /Pd nanocomposite as an efficient and green synthesized catalyst for hydrogen evolution reaction
Didem Balun Kayan, Ersan Turunç
Abstract
In this work, we introduced a green methodology for the production of palladium (Pd) decorated reduced graphene oxide (rGO), using an endemic plant of Onosma malatyana Binzet (OMB) root extract for the first time and used it as an electrocatalyst for hydrogen evolution reaction (HER) in aqueous acidic media. Benefiting from the synergetic effect between rGO and Pd nanoparticles, the as-prepared bio-reduced GO/Pd (bio-rGO/Pd) nanocomposite exhibits a remarkable performance towards HER when the results compared with the bio-rGO and bio-rPd nanocomposite. The HER overpotential at a current density of 10 mA cm−2 for bio-rGO/Pd was only 0.17 V. The Tafel slope of the bio-rGO/Pd nanocomposite film obtained from the HER polarization curves exhibits 154 mV dec−1, showing that the process is limited by the Volmer reaction step. In addition, the bio-rGO/Pd nanocomposite electrode also showed an outstanding stability after a long-term potential cycling measurement. It possesses a high synergetic effect, low charge transfer resistance and considerable electrochemical surface area. The all obtained results demonstrated that the bio-rGO/Pd will be a promising green synthesized HER catalyst.