Grown of highly porous ZnO-nanoparticles by pulsed laser ablation in liquid technique for sensing applications

Abstract

Pulsed laser ablation technique in deionized water with low laser fluency has been explored to prepare uniform dispersed porous ZnO nanoparticles for sensing applications. Surface morphology, particle size, porous structure, roughness, elemental distribution, and chemical bonding of the synthesized ZnO are analyzed by TEM, FESEM, AFM, EDX, and FTIR spectroscopy, respectively. Sensing behavior is observed by UV–Vis absorption measurements. TEM and FESEM analysis show that the prepared ZnO-coated film has homogeneous, dispersed, highly porous, and crack-free surface; the average particle size are observed ~ 24.72 ± 2.97 nm. The porous structure is responsible for appropriate sensing behavior. Low roughness value ~ 1.52 nm which is analyzed by AFM is advantageous for sensing behavior. EDX spectrum and elements mapping clearly show the uniform Zn and O distribution. XRD analysis confirms the hexagonal wurtzite structure of ZnO. FTIR reveals the Zn and O chemical bonding successfully. UV-Visible analysis exhibits that the prepared ZnO matrix has good incorporation with multi-dyes solutions at pH values 10–12 with significant changes in color behavior. The highest pKa value ~ 9.77 at a wavelength of 598.28 nm was calculated for multi-dyes immobilized ZnO matrix. So, it can be concluded that prepared ZnO nanostructures are potential candidates for sensing application.