Highly Efficient Electrochemical Hydrogen Evolution Reaction at Insulating Boron Nitride Nanosheet on Inert Gold Substrate

Abstract

It is demonstrated that electrochemical hydrogen evolution reaction (HER) proceeds very efficiently at Au electrode, an inert substrate for HER, modified with BNNS, an insulator. This combination has been reported to be an efficient electrocatalyst for oxygen reduction reaction. Higher efficiency is achieved by using the size controlled BNNS (<1 μm) for the modification and the highest efficiency is achieved at Au electrode modified with the smallest BNNS (0.1–0.22 μm) used in this study where overpotentials are only 30 mV and 40 mV larger than those at Pt electrode, which is known to be the best electrode for HER, at 5 mAcm−2 and at 15 mAcm−2, respectively. Theoretical evaluation suggests that some of edge atoms provide energetically favored sites for adsorbed hydrogen, i.e., the intermediate state of HER. This study opens a new route to develop HER electrocatalysts.

Oxygen Reduction Reaction Catalyzed by Small Gold Cluster on h-BN/Au(111) Support

“…Therefore, a metal substrate or defects in h-BN can promote or affect catalytic reactions on the h-BN surface [38]. This theoretical suggestion has been proved experimentally where it has been demonstrated that Au electrodes modified with boron nitride nanosheet (BNNS) in the acid media indeed can act as effective electrocatalysts not only for ORR [47,48], but also for the hydrogen evolution reaction (HER) [49]. It has been demonstrated that overpotential for ORR at gold electrode is reduced by 0.27 V by the modification with BNNS, although it is still high compared with Pt electrode and oxygen is mainly reduced to H 2 O 2 via 2electron process [47,48].…”

Metal support effects in electrocatalysis at hexagonal boron nitride

“…7 Although it is intrinsically insulating (i.e., band gap of 3.6 to 7.1 eV), 8 hexagonal boron nitride (h-BN) has attracted considerable attention in oxygen reduction reaction (ORR) 9,10 and hydrogen evolution reaction (HER) catalysis. 11 This is because the band gap of monolayer h-BN can be considerably reduced by introducing defects such as B/N vacancies and impurities, 12 and tuned to an extent through decoration with hydrogen atoms. 13 Moreover, as electron tunneling through ultrathin h-BN layers is possible, 14 electronic interaction with the underlying metal support substrate (i.e., through mixing of the d z 2 metal orbitals with the N-p z and B-p z orbitals of h-BN) can tune electrochemical (electrocatalytic) activity.…”

Two‐Dimensional Amorphous Cr2O3 Modified Metallic Electrodes for Hydrogen Evolution Reaction

“…For an ideal electrocatalyst, it has to be in thermoneutral, that is, Δ G H ∼0 eV – meaning adsorption and desorption (of H 2 ) energy should be optimum . The reported theoretical frameworks for 2D materials modified metals mostly hold in an acidic medium where either adsorption/desorption energy optimization or Fermi level modification are proposed as the basic mechanism aiding for higher activities . Subbaraman et al proposed a different mechanism for improved electrocatalysis of electrodeposited 3d‐metal oxyhydroxides on a gold electrode in alkaline medium .…”