Improved ethanol sensing characteristics of sol–gel derived nanocrystalline manganese doped lithium tetraborate

• Nanostructures of Manganese doped Li2B4O7was synthesized following sol–gel method.
• Role of ionic radii on increasing the lattice constants were discussed.
• Above 90% optical transparency was achieved after the addition of Manganese.
• Low doping level in Li2B4O7 gives rise to high ethanol gas sensitivity.

Manganese doped lithium tetraborate (LTB:Mn) nanoparticles were prepared by Sol–Gel method and characterized by XRD and FESEM. The UV–vis spectrum shows an enhanced transparency for LTB:Mn (90%) compared with pure LTB (∼60%). Using fiber optic gas sensing setup, the gas sensitivity was investigated for different concentrations (0, 100, …, 500 pm) of ethanol. The sensitivity of pure, 0.01 M, 0.03 M and 0.05 M LTB:Mn were determined as −10, 18, 12 and −17 counts/100 ppm respectively. 0.01 M LTB:Mn shows better sensitivity for ethanol gas.