Abstract
ZnO nanostructures prepared at different pH (9 and 11) were functionalized with naphthalene appended diketopyrrolopyrrole derivatives with thiophene (TDPP) and phenyl (PDPP) functionals. The functionalization was ascertained through various characterization techniques like XRD, FESEM, UV-Visible absorption and PL studies. Gas adsorption-induced surface potential of functionalized samples were studied through scanning Kelvin probe system at room temperature in the presence of various volatile organic compounds (VOCs) like acetone, benzene, ethanol, nonanal, n-hexane, 1-hexanol and triethylamine (TEA). Interestingly, the functionalized ZnO nanostructures obtained at pH 9 showed ~1.5 times better response towards 1-hexanol when compared to the functionalized pH 11 ZnO counterparts. Density functional theory calculations revealed that the DPP derivatives showed higher binding affinity towards ethanol, 1-hexanol and nonanal. Overall, this combined experimental and computational studies suggested that the DPP derivatives functionalized ZnO nanostructures would be useful for detection of VOCs such as alcohols and aldehydes.
