Synthesis and Characterization of Copper Doped Zinc Oxide Thin Films for CO Gas Sensing

TL;DR

This study developed copper-doped zinc oxide thin films optimized for CO gas sensing, demonstrating that specific synthesis parameters significantly enhance sensitivity and surface properties.

Contribution

It introduces a systematic optimization of synthesis parameters for CZO films to improve CO gas sensing performance.

Findings

Optimal sensitivity at 0.75 M molarity, 3% copper, 300°C annealing.

Surface roughness of 3.90 nm and grain size of 256 nm achieved.

Annealing temperature significantly affects sensitivity.

Abstract

Objective of this work was to synthesize Copper doped Zinc Oxide (CZO) films and optimization of process parameters by varying molarity of zinc acetate dehydrate from 0.5 M to 1.0 M, concentration of copper acetate monohydrate from 1% to 5 % and annealing temperature from 200 C to 300 C to measure the sensitivity of CZO films for CO (Carbon Monoxide) gas. The concentration of CO gas was maintained at 5 ppm and operating temperature of 250 oC was used for sensing. Analysis for sensitivity showed highest grading for parametric combination of 0.75 molarity, 3% copper concentration and 300 C annealing temperature with surface roughness of 3.90 nm and grain size of 256 nm. TEM image revealed the crystalline grain size was 5 nm. ANOVA showed that annealing temperature influenced the sensitivity by 69.06 % .