In most journals, TiO2 sols produced by dissolved titanium isopropoxide in isopropanol solvent. Can I replace isopropanol with ethanol as solvent medium and using HCl as peptizing agent?
In a short answer, yes. I've done the same myself. The usual (and main) reason for the use of propan-2-ol is that 100% ethanol (and this is what you need) is taxed heavily in countries that think you may drink it. IPA (propan-2-ol) is often considerably cheaper. In either case the alcohol must be scrupulously dry - the azeotrope with water for ethanol is 4% water and I think 2.5% water for propan-2-ol Both alcohols are hygroscopic and pick up moisture easily. I think HCl gas is soluble in IPA and ethanol to a similar extent.
In a short answer, yes. I've done the same myself. The usual (and main) reason for the use of propan-2-ol is that 100% ethanol (and this is what you need) is taxed heavily in countries that think you may drink it. IPA (propan-2-ol) is often considerably cheaper. In either case the alcohol must be scrupulously dry - the azeotrope with water for ethanol is 4% water and I think 2.5% water for propan-2-ol Both alcohols are hygroscopic and pick up moisture easily. I think HCl gas is soluble in IPA and ethanol to a similar extent.
Yes, it can be substituted. However, you should prepare the solution shortly before you perform your experiment. Otherwise, the titanium iso propoxide will exchange and partially become titanium ethoxide. The later has a different reaction rate and the resulting product will be "different".
As long as you perform all experiments in the same way (time-wise) there should not be any major problems.
I've found method for synthesize N-doped TiO2 nanoparticle like this:
An adequate amount of Ti(OiPr)4 (0.1 M) was placed in isopropyl alcohol (100 mL) and the solution was agitated vigorously at 60 C for 30 min. Subsequently, 3.64 g of HDTMA was dissolved in distilled water (100 mL) to fix the generation of nitrogen and various silica sols (0, 0.1, 1, 10, and 100 mM) were added to the HDTMA solution and mixed for 30 min.
Can I do this procedure but replace isopropyl alcohol with ethanol? Is it true that HDTMA-Br can be used as nitrogen source doping?
@ Allouche Are you using 100% ethanol? The azeotrope is 96% EtOH and 4% water. The latter will cause hydrolysis of the propoxide. You need to dry your EtOH over anhydrous sodium sulfate. Distillation doesn't work for an azeotrope.
Yes, pretty much all alkoxides are VERY sensitive to moisture. The only exception to that rule is TEOS, which you can actually mix with water and no apparent reaction occurs (unless acid or base is added).
For that reason all reactions with alkoxides should be closely controlled with regard to water exposure.
TEOS is generally taken to mean tetraethylorthosilicate. With your ispropoxide (TTIP) then reaction with water is instant as you have found out. Your TTIP is not obsolete - it's reacting as expected. That's why moisture exclusion is so important until it's needed.
There other phenomenon is observed when I add ethanol (96% or 99.8%) the milky solution is obtained and when adding HCl 37% to this mixture the limpid solution is obtained spontaneously