Hydrazine-assisted electrochemical water splitting is an important avenue toward low cost and sustainable hydrogen production, which can significantly reduce the voltage of electrochemical water splitting. Herein, we took a simple approach to fabricate NiFeP nanosheet arrays on nickel foam (NiFeP/NF), which exhibit superior electrocatalytic activity for the hydrogen evolution reaction (HER) and the hydrazine oxidation reaction (HzOR). Our investigations revealed that the excellent electrocatalytic activity of NiFeP/NF mainly arises from the bimetallic synergistic effect, abundant electrocatalytically active sites facilitated by the porous nanosheet morphology, high intrinsic conductivity of NiFeP/NF and strong NiFeP–NF adhesion. We assembled a hydrazine-boosted electrochemical water splitting cell using NiFeP/NF as a bifunctional catalyst for both electrodes, and the overall hydrazine splitting (OHzS) exhibits a considerably low overpotential (100 mV at 10 mA cm−2), and is stable for 40 h continuous electrolysis in a 1 M KOH + 0.5 M N2H4 electrolyte. When it is applied to hydrogen production by seawater electrolysis, its catalytic activity shows strong tolerance. This work provides a promising approach for low cost, high-efficiency and stable hydrogen production based on hydrazine-assisted electrolytic seawater splitting for future applications.
Xiao Chen,Yating Hou,Jinghan Xu,Ningyuan Song,Xinru Wei,Yanru Liu,Kang Liu,Yunmei Du,Lei Wang
Nowadays, the electrocatalytic regulation mechanism of quantum dots (QDs)-supported materials is limited to strong metal-support interaction (SMSI) and electron-metal-support interaction (EMSI). However, the lattice strain of the carrier induced by QDs is neglected, which is not conducive to the directional design of the QDs-supported electrode and the establishment of its structure-performance correlation. Given these, the size and distribution of Pt QDs controlled by electrodeposition effectively regulate the strain degree on S-NiFeP nanosheets. DFT results reveal that Pt@S-NiFeP/NF complies with a Fe-Pt dual active sites mechanism for alkaline HER, and a Fe active site mechanism for OER. Interestingly, the compressive strain in the S-NiFeP substrate effectively promotes the d‐band center shift and the energy barrier reduction, thereby optimizing the alkaline HER and OER kinetics. As expected, Pt@S-NiFeP/NF with appropriate strain owns alkaline HER and OER performance at 1 A cm −2 that exceeds the commercial Pt/C and RuO 2 . Overall, this work has guided the structural design of the 'noble metal QDs@carrier' model and laid a foundation for its application at ampere-level current densities.