Production of coronene/2–3% Al:CdO nanocomposite heterojunctions by hybrid methods and comparison of optoelectronic properties

Coronene organic semiconductor was coated by thermal evaporation method on 2–3% Al-doped CdO thin films produced by electrochemical deposition method and the structural, optical and electrical properties of the heterojunction were investigated to offer an option for optoelectronic application. The surface analysis of 2–3% Al-doped CdO films and the coronene layer grown on these surfaces and it was seen that the 2–3% Al:CdO layers were composed of microcrystals and grains, and the coronene layer was composed of nanowires. It was seen that in the optical analysis that the increase of Al contribution into CdO increased the absorption coefficients of heterojunctions (from 1.21 × 10 6 to 2.04 × 10 6 m −1 ) and direct energy band gap (from 2.22 to 2.69 eV). Ag/coronene/2–3% Al:CdO/Ag devices were prepared for electrical analysis. Photodiode and photodetector parameters of the heterojunctions were investigated under dark and different light intensities (20–100 mW cm −2 ). The diode ideality factor ( n ), barrier height ( ϕ b ) and reverse saturation current ( I 0 ) values of Ag/coronene/2% Al:CdO/Ag photodiode were found to be 7.99–5.72, 0.65–0.63 eV and 1.5 × 10 –6 to 1.45 × 10 –4 A, respectively, while the n , ϕ b and I 0 values of Ag/coronene/3% Al:CdO/Ag photodiode were found to be 2.98–2.16, 0.46–0.47 eV and 1.6 × 10 –3 to 2.3 × 10 –3 A, respectively.The maximum photocurrent ( I ph ), photoresponsivity ( R ph ), photosensitivity ( S ) and specific detectivity ( D* ) values of Ag/coronene/2% Al:CdO/Ag photodiode were found to be 7.09 × 10 –4 A, 23.57 A W −1 , 1.35 × 10 –4 S m W −1 and 1.18 × 10 13 Jones, respectively, while the maximum I ph , R ph , S and D* values of Ag/coronene/3% Al:CdO/Ag photodiode were found to be 1.9 × 10 –3 A, 33.22 A W −1 , 1.9 × 10 −4 S m W −1 and 3.85 × 10 11 Jones, respectively. When the calculated photodetector parameters were compared to literature, it was evident that the values we discovered were fairly high.Additionally, heterojunctions displayed photovoltaic action, and the highest FF% values were found to be around 30%.