Numerical analysis and performance improvement of nanostructured Cu 2 O/TiO 2 pn heterojunction solar cells using SCAPS Kingsley Ukoba ⇑ , Patrick Ehi Imoisili, Tien-Chien Jen Mechanical Engineering Science Department, University of Johannesburg, Auckland Park, South Africa article info Article history: Received 30 January 2020 Received in revised form 1 May 2020 Accepted 5 May 2020 Available online xxxx Keywords: Cu 2 O Performance Nanostructured Thin films solar cells Surface thickness abstract This paper reported numerical analysis and performance improvement of nanostructured Cu 2 O/TiO 2 pn heterojunction solar cells. Metal oxides thin films including Copper oxides are promising materials for photovoltaic applications. Although, the efficiency is still lower than other solar cells materials. This paper focused on improving the efficiency of Cu 2 O/TiO 2 solar cells using SCAPS simulation tool. This was done by varying the effect of film surface thickness and effect of varying deposition temperature on the solar cells. The purpose of the study is to provide a theoretical guide for laboratory research on the improvement of efficiency of Cu 2 O metal oxide solar cells. The motivation of the study is that Solar cells with thin absorber surface thickness will result in lower fabrication cost. The solar cells equations were modelled and thereafter theoretical validation of the nanostructured metal oxides was performed. The model used a working points input power of 100 mW/m 2 with AM1.5 lamp illumination. The mod- elled solar cell exhibits a short-circuit current (J sc ) of 26.57 mA/cm 2 , 0.7188 V open-circuit voltage (V oc ), fill factor (FF) of 70, and 13.37% efficiency (g). A value of 2.30 eV was recorded for the band gap. Also, electron affinity and Nyquist plot were obtained for the solar cells. This will open a new frontier for mod- elling of metal oxide based thin films solar cells especially Cu 2 O thin films solar cells. Ó 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Symposium on Nanostructured, Nanoengineered and Advanced Materials. 1. Introduction The growing demand for energy and the adverse effect of fossil fuel on the planet continues to favor research on clean and sustain- able energy. Nanostructured metal oxides continue to attract inter- est owing to their versatility in energy applications [1–4]. Nanostructured metal oxide (NMO) has good band gaps, afford- able, tenable, abundant and environmentally friendly [5]. However, laboratory experimental results are yet to rival conventional sili- con solar cells in terms of efficiency and performance. The numer- ical analysis of solar cells acts as a guidepost for faster and better experimental results [6]. Efficiency of solar cells is affected by sev- eral factors including the film surface thickness, surface roughness [7,8]. Hence, this study examined the effect of thickness and tem- perature with aim of improving the performance of Cu 2 O/TiO 2 pn heterojunction solar cells. Cuprous oxide (Cu 2 O) solar cells have been studied lately. The cuprous oxide is low cost, plentiful, and non-hazardous, with over 20% under air mass 1 solar illumination [9]. It has an optical and direct band gap of 2.62 eV and 2.17 eV respectively [10,11]. Cu 2 O has a low affinity of 3.2 eV [12]. It has high hole mobility of 256cm 2 V À1 s À1 and hole concentration of 1 Â 10 14 cm À3 [13]. This makes Cu 2 O a good hole transport p-type material in fabricating heterojunction solar cells. However, TiO 2 is an n-type material with a wide band gap in the range of 3.6 eV to 3.2 eV. TiO 2 has been studied greatly due to their favourable electronic and optical prop- erties [14]. TiO 2 durability and high refractive index make the material useful for optical coating and anti-reflection coating. It is compatible with the n-type material used in heterojunction with several p-type materials [15]. Although, NMO still exhibits weak conversion efficiency with the maximum efficiency being around 8.4% [16]. This has resulted in several duplications of resources in the laboratory in an attempt to achieve better efficiency comparable with those of CIGS solar cells of over 20% [17]. Different laboratory procedures have been developed to deposit metal oxides with a view of obtaining better efficiency [18–21]. However, solar numerical analysis can be used to obtain improved efficiency without the bottleneck of experi- mental expenses. Solar numerical analysis has been around but https://doi.org/10.1016/j.matpr.2020.05.111 2214-7853/Ó 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Symposium on Nanostructured, Nanoengineered and Advanced Materials. ⇑ Corresponding author. E-mail addresses: ukobaking@yahoo.com, kukoba@uj.ac.za (K. Ukoba). Materials Today: Proceedings xxx (xxxx) xxx Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr Please cite this article as: K. Ukoba, P. E. Imoisili and T. C. Jen, Numerical analysis and performance improvement of nanostructured Cu 2 O/TiO 2 pn hetero- junction solar cells using SCAPS, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2020.05.111