Is there any process by which one can form Sol gel nickel oxide films at lower temperature (less than 200 to 250C) ?
Chetan Singh , In general, you can get thin films by dip-coating or spin-coating of sol-gel derived solution. But of course the coating you prepare is not fully crystalline, so you need to anneal it. In your case, you have NiO. At room temperature, you can get NiO coating but it would not be fully crystalline, so you need to heat-treat to get crystalline structure.
However, we have the experience that if the film thickness is extremely thin, then there is a chance to get crystalline film even without annealing. I hope this helps.
We prepared ZnO thin films using spin coating, chemical bath deposition and dip coating technique. In CBD temperature was 70 degree centigrade. Other two were in room temperature. Though these methods do not provide 100% uniform crystalline samples, they are really easy and convenient to carry out. Sometimes you may not even get a XRD peak. But if you anneal the samples at certain temperature you will definitely see the change from before annealing state.
