The effect of MnO_{2 concentration on the formation of MnO_{2/ZnO thin films with bifunctional thermal insulation and photocatalytic self-cleaning performance

This study focuses on fabricating manganese dioxide/zinc oxide (MnO2/ZnO) thin films using a two-stage chemical bath deposition (CBD) technique. The concentration effect of MnO2 thin film for the second stage deposition will be optimised and selected based on their thermal conductivity behaviour. It was found out that the wettability showed an increase in the contact angle (CA) after the addition of ZnO, with the highest CA of 14.5°C for 12% of ZnO. The same sample also demonstrated commendable thermal performance after reaching a constant temperature of 35.9°C in 65 minutes compared to the uncoated glass substrate. All thin films indicated low photocatalytic activity, where the best sample (12% of ZnO loading) yielded only 6% degradation efficiency of 10 mgL-1 malachite green (MG) as a model pollutant within 90 minutes. The porosity and agglomeration gradually increased following second stage deposition and ZnO introduction.