I have a bottle of titanium dioxide nanoparticle powder and I want to cover it with anything, such as metal, protein or different things. However I don't know this process and I need help. Can anybody help me?
You can try some simple chemical reactions. You can mix the two references and you have many directions: [http://www. chalcogen.ro/1339_Corobea.pdf] and [C-W Hung et al Towards oriented assembly of proteins onto magnetic nanoparticles
I would wrap the titanium dioxide nanopowder in aluminum foil. Then you will have aluminum foil covered titanium nanopowder. Sorry that is a joke, the question is just phased funny. We normally wouldn't say we are trying to cover the nanoparticles, but instead coat the nanoparticles may be a better phrase.
You could put the TiO2 in a solution of bovine serum albumin (BSA) or fetal bovine serum (FBS) and disperse the nanoparticles in the solution by sonication or microfluidic methods. The particles will become coated with the proteins in the BSA or FBS. This can however agglomerate the nanoparticles or lock in the agglomerates in the titanium nanopowder.
You also created a very broad topic here. I would suggest doing a literature search on doping titanium dioxide nanopowders with metals, coating them with PEG and other proteins as mentioned before BSA, FBS, as you should be able to find many.
Can I ask why you want to coat them? You may be reducing their reactivity and photocatalytic properties by doing so.