I have prepared tin and tin oxide nanoparticles using laser ablation method. I have fixed the time and wavelength but vary the laser energy and liquid media ( acetone, ethanol and methanol). The XRD result shows that at 30 mJ laser energy minimum or no oxide peak was observed when compared it to samples prepared at high energy i.e 60 mJ. No oxide peaks was observed when particles were prepared in methanol at 30 laser energy. I don't know why?
Ethanol is more electronegative then acetone and methanol .It is more difficult to break the bonds of ethanol but still at low energy different oxide peaks were observed when compared it to methanol. What might be the reason?
Since the liquid media is very important to donate oxygen so ethanol, Methanol, acetone contribute differently in the synthesis of metal oxides. If you add H2O2 as oxidizing agent you can even generate ZnO2 instead ZnO. Please read some of our papers in this domain (gondal et al). In addition, the particle size can also be controlled by adding various surfactants. Laser energy is very important parameter in generation of plasma inside the aqeous media so products will then change based of incident laser energy.
The physics behind PLAL is complicated but your question why you get metal oxides formation in acetone and not in methanol and ethanol is basically the ability to release oxygen. If you have higher concentration of acetone and you run yr experiment at higher energy it will catch fire. What it means is that you are are generating more atomic oxygen. In ethanol and methanol u will not experience such phenomenon. Regarding physics of PLAL
U create a plasma inside the aqeous medium and high temperature at certain point while surrounding material is at room temperature and this way u creat temp and pressure gradient which creates shock wave resulting in compressing of the bulk material to generate nano particles. Since u creat plasma and ionic and electrons species and then these recombine to make oxides etc. Which depends on the solvent what u use. Even in water u can produce at high energy oxides and try for Zn at 200 mj j. It will work even in water or easily in H2O2. If u have further queries u can send ur questions or read our papers.
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