| Nickel-rich oxide nanowires have the potential of being used in several energy applications but require a reliable growth technique. A novel synthesis method has recently been discovered that promises the ability to generate self assembled, high quality, and high density nickel-rich oxide nanowires. The nanowires have been grown on substrates of Alloy 600 (Ni-15%Cr-8%Fe) and other nickel-chromium alloys exposed to oxidizing conditions in high temperature, high pressure systems. Due to the nanowires' fortuitous but unexpected discovery, there is a significant amount of work on many facets that must be performed to understand their growth and maximize their utility. Several of the growth parameters (applied electrochemical potential, temperature, solution chemistry, substrate composition, and time) have been investigated. Results from these experiments are used to propose a growth mechanism. Thus far, the as-grown nanowires from an Alloy 600 substrate have been shown to possess a composition of 49a/o oxygen, 47a/o Ni, and 4a/o Fe, large aspect ratios (average diameter of 25nm and lengths up to 10mum), and to be single crystalline. Magnetic measurements have also shown that the nickel-rich oxide nanowires are ferromagnetic with a coercivity of approximately 85Oe and a remnant field of 0.032emu/g at 300K. The nanowires have been recently applied as electrodes in environments simulating Li-ion batteries and Ni-metal hydride batteries. The initial results have been positive and suggest the use of nanowires in battery applications is promising. |
