Ni(OH)2 nanoparticles encapsulated in conductive nanowire array for high-performance alkaline seawater oxidation

Design and development of high-efficiency and durable oxygen evolution reaction (OER) electrocatalysts is crucial for hydrogen production from seawater splitting. Herein, we report the in situ electrochemical conversion of a nanoarray of Ni(TCNQ)2 (TCNQ = tetracyanoquinodimethane) on graphite paper into Ni(OH)2 nanoparticles confined in a conductive TCNQ nanoarray (Ni(OH)2-TCNQ/GP) by anode oxidation. The Ni(OH)2-TCNQ/GP exhibits high OER performance and demands overpotentials of 340 and 382 mV to deliver 100 mA·cm−2 in alkaline freshwater and alkaline seawater, respectively. Meanwhile, the Ni(OH)2-TCNQ/GP also demonstrates steady long-term electrochemical durability for at least 80 h under alkaline seawater.