Montmorillonite decorated with 3D porous interwoven spiky NiCo-LDH as an advanced bifunctional electrocatalyst for boosting alkaline water electrolysis

Electrocatalytic water splitting is considered a clean and sustainable strategy for producing hydrogen as a pollution-free energy carrier, which can address the energy crisis. Hence, developing cost-effective and high-performance bifunctional electrocatalysts for alkaline water splitting is crucial for pushing forward the hydrogen energy technology. In this paper, NiCo-LDH with varying xNi:yCo molar ratios (2:1, 1:1, and 1:2) was grown onto montmorillonite (xNi:yCo-LDH@MMT) supported nickel foam using a hydrothermal process. Particularly, 1Ni:1Co-LDH@MMT delivers an overpotential of 210 mV to achieve a current density of 20 mA/cm 2 for oxygen evolution reaction (OER), and 48 mV at a current density of 10 mA/cm 2 for hydrogen evolution reaction (HER). Moreover, the assembled 1Ni:1Co-LDH@MMT (+/−) cell requires a quite low voltage of 1.52 V to drive 10 mA/cm 2 and also exhibits outstanding durability in alkaline electrolyte for 40 h. Such good performance could be owing to: (1) MMT as support provides strongly anchoring of 1Ni:1Co-LDH on its surface, which results in enhanced stability of the catalyst; (2) The 1Ni:1Co-LDH can improve electrical conductivity, thereby suggesting rapid kinetic process; (3) The unique 3D porous interwoven spiky morphology of 1Ni:1Co-LDH offer numerous active sites, and is beneficial for accelerating the charge/mass transport. This work opens up a new opportunity for the manufacture of non-precious bifunctional electrocatalysts for applications in energy conversion.