Fig. 6: TE properties of optimised sample.

a AZO which has the following parameters 3% aluminium doping, annealing at 500 °C, deposited for 1.5 h. b CuI sample which has the following parameters: a cationic precursor concentration of 0.075 NaI, 20-s immersion, annealing at 150 °C, and 40 immersion cycles. The effect of substrate on the thermoelectric performance of CuI illustrates in (c) electrical conductivity d Seebeck measurements. The error bars of TE properties of optimised sample were determined by standard deviation (SD) from five independent measurements conducted at each temperature point. The SD reflects the variability observed across these trials, indicating the reproducibility of the data. The standard deviation and error bars were calculated using Origin Pro 2024 software.