Enhancement of power conversion efficiency of Al/ZnO/p-Si/Al heterojunction solar cell by modifying morphology of ZnO nanostructure

• Published in: Journal of materials science. Materials in electronics Vol. 31; no. 5; pp. 4142 - 4149
• Main Authors: Narzary, Rewrewa, Phukan, Palash, Maity, Santanu, Sahu, Partha Pratim
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-03-2020; Springer Nature B.V
• Subjects: Aluminum; Annealing; Characterization and Evaluation of Materials; Chemistry and Materials Science; Circuits; Crystal structure; Crystallinity; Energy conversion efficiency; Heterojunctions; Materials Science; Morphology; Nanostructure; Open circuit voltage; Optical and Electronic Materials; Photovoltaic cells; Short circuit currents; Silicon; Sol-gel processes; Solar cells; Visible spectrum; Zinc oxide
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-020-02962-2

This paper proposes a cost-effective sol–gel method for synthesis of ZnO nanostructure to make Al/ZnO/p-Si/Al heterojunction solar cell. Here, crystalline ZnO nanostructure was grown on p-silicon and annealed at 300 °C, 400 °C and 500 °C for application in heterojunction solar cell. The optimum temperature for obtaining uniform crystalline nanostructure was 500 °C, as confirmed from XRD and SEM imaging. As investigated by UV–Vis spectroscopy, the ZnO nanostructure layer exhibited high transmittance in the visible spectrum and has a direct band gap of 3.26–3.28 eV. The power conversion efficiency of Al/ZnO/p-Si/Al solar cell is enhanced from 1.06 to 2.22% due to increase in surface area of ZnO by formation of crystalline nanostructure due to increase of annealing temperature. The optimum value of short-circuit current (
I
sc
) and open-circuit voltage (
V
oc
) was measured using current–voltage (I–V) under AM 1.5 illuminations and found to be 9.97 mA and 460 mV, respectively.