Tungsten phosphide nanorod arrays directly grown on carbon cloth: a highly efficient and stable hydrogen evolution cathode at all pH values.

We report the development of tungsten phosphide nanorod arrays on carbon cloth (WP NAs/CC) through a two-step strategy: hydrothermally growing WO3 nanorod arrays on CC (WO3 NAs/CC) first, followed by phosphidation to chemically convert the WO3 NAs/CC precursor into WP NAs/CC. As a novel integrated 3D hydrogen evolution cathode in acidic media, the WP NAs/CC electrode exhibits excellent catalytic activity and durability. It needs overpotentials of 130 and 230 mV to afford current densities of 10 and 100 mA cm(-2), respectively, and its catalytic activity is maintained for at least 70 h. Remarkably, this electrode also works efficiently in both neutral and alkaline solutions.