https://nova.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Nitrogen-promoted molybdenum dioxide nanosheets for electrochemical hydrogen generation https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36477 2 sheets with excellent stable Pt-like HER performance. A simple and repeatable strategy has been developed via the use of the cheap, simple small organic molecule urea as a reducing agent. We confirm that N doping can induce a disordered surface lattice and increase the number of proton adsorption sites with a relatively weak binding force. Owing to the cooperative effects of surface N doping, disordered surface distortion and the intrinsic nature of MoO2, high HER activity can be achieved, with an overpotential of η = 96 mV vs. RHE at a current density of −10 mA cm−2 and a Tafel slope of 33 mV per decade. Moreover, we further extended the synthesis method to Ni and Co systems with the formation of N–NiO/Ni and N–CoO/Co core–shell structures, which exhibited enhanced HER performance in comparison with bare MO/M (M = metal) samples. This study can help us design new earth-abundant electrocatalysts with further enhancements in catalytic performance.]]> Tue 19 May 2020 13:15:39 AEST ]]> Single atom tungsten doped ultrathin α-Ni(OH)₂ for enhanced electrocatalytic water oxidation https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35062 6+ doped Ni(OH)₂ nanosheet sample (w-Ni(OH)₂) with an outstanding oxygen evolution reaction (OER) performance that is, in a 1 M KOH medium, an overpotential of 237 mV is obtained reaching a current density of 10 mA/cm². Moreover, at high current density of 80 mA/cm², the overpotential value is 267 mV. The corresponding Tafel slope is measured to be 33 mV/dec. The d⁰ W6+ atom with a low spin-state has more outermost vacant orbitals, resulting in more water and OH- groups being adsorbed on the exposed W sites of the Ni(OH)₂ nanosheet. Density functional theory (DFT) calculations confirm that the O radical and O-O coupling are both generated at the same site of W6+. This work demonstrates that W6+ doping can promote the electrocatalytic water oxidation activity of Ni(OH)2 with the highest performance.]]> Mon 19 Aug 2019 16:37:22 AEST ]]> Air-stable phosphorus-doped molybdenum nitride for enhanced elctrocatalytic hydrogen evolution https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35061 2, respectively, in 0.5 M H2SO4 solution with a small Tafel slope of 43 mV/dec. Thus it outperforms many of the state-of-art molybdenum-based hydrogen evolution catalysts reported to date.]]> Mon 17 Jun 2019 12:09:40 AEST ]]>