Ionic liquid crystals modifier to NiOnano@MWCNTs for effective electrocatalytic water splitting and hydrazine degradation

Ionic liquid crystals (ILCs) are employed as a “benign” modifier for Ni-electrode to facilitate the ionic exchange of hydroxyl ions that is critical for the hydrazine oxidation reaction (HyzOR). Further, a layer of carbon nanotubes (CNTs) decorated with NiO nanoparticles (NiO _nano ) is drop-cast at the interface. Due to its high thermodynamic potential, 1.23 V vs. RHE and slow kinetics of the oxygen evolution reaction (OER), electro-catalytic water splitting (WS) is hindered. HyzOR precedes the OER at a lower potential and is facilitated by ILCs that exchange the OH ^– ions. The OER takes place at the Ni/ILCs/NiO-CNTs at an onset potential of + 0.852 V (vs. RHE) in the presence of Hyz with a driven specific current density of 94.8 A.cm ^-2 .g ^-1 and lowering the overpotential by 0.85 V. The present approach realizes the minimization of the toxic and health hazards of Hyz-contaminated aquatic media and concurrently splits water to generate oxygen and hydrogen gases with minimal energy requirement. Thus, 4.22 moles of Hyz are degraded and 8.44 moles of H ₂ are generated while consuming 1.33 × 10 ^–4 W.hr and 6.67 × 10 ^–5 W.hr, respectively, reaching 230% efficiency.