Abstract: We prepared sol-gel samples by hydrolysis of tetraethyl orthosilicate (TEOS). FTIR studies are done on the samples heated at different temperatures to confirm the glassy network. Porosity studies confirmed the pore size of around 22nm. Acid /Alkali indicators like methyl orange, phenolphthalein and universal indicator doped sol-gel glasses are prepared. These glasses can be used as acid/alkali reversible solid indicators. V-I characteristics are drawn for these glasses using a diode laser photo detector set up. These glasses find application as a solid-pH sensor. Samples are also prepared by doping them with suitable chemicals which find application as a sensor for industrial chemical leakage.

Keywords: sol-gel process, industrial chemical sensor, pH sensor, porosity studies.