Single platinum atoms implanted 2D lateral anion-intercalated metal hydroxides of Ni2(OH)2(NO3)2 as efficient catalyst for high-yield water splitting

Abstract

In this study, we report new electrocatalysts based on 2D anion-intercalated metal hydroxides of Ni2(OH)2(NO3)2 (2D NiHN) and its derivation caused by the implantation of single platinum atoms (PtSA–2D NiHN). The optimum PtSA−1.73–2D NiHN material having low Pt loading of 1.73 wt% exhibits prospective HER activities with an overpotential (η) of 24 mV at 10 mA cm−2, while the 2D NiNH requires an η of only 280 mV to reach 50 mA cm−2 for OER. The assembly of PtSA−1.73–2D NiHN-based cathode and 2D NiHN-based anode to fabricate a two-electrode electrolyzer of PtSA−1.73–2D NiHN(−)//2D NiHN(+) allows a cell voltage of only 1.45 V at 10 mA cm−2 for overall water splitting, superior to RuO2(+)//Pt/C(−). The device also exhibits prospective long-term stability in 1 M KOH. The achievements suggest that the PtSA−1.73–NiHN and 2D NiHN catalysts are two potential candidates for water splitting application.