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Rapid preparation of CdSe thin-film solar cells

Peer-Reviewed Publication

Higher Education Press

Rapid preparation of CdSe thin-film solar cells

image: (a) Schematic diagram of RTE. (b) Schematic diagram of CdSe solar cells design based on bandgap engineering. view more 

Credit: Higher Education Press Limited Company

Si-based tandem solar cell is regarded as the most promising strategy to break the theoretical efficiency limit of single-junction Si solar cells. With Si as the bottom cells, the optimal bandgap of top cells is 1.7 eV, which enables high efficiency of ~45% for two-junction tandem solar cells. III-V semiconductors/Si and perovskites/Si tandem solar cells have achieved high efficiency of ~30%, proving the feasibility. However, the stability challenges of perovskite and the high-cost problem of III-V semiconductors largely limit their wide applications. Exploring new stable, low-cost, and bandgap 1.7 eV photovoltaic materials is of great significance in science and broad prospects in technology.

Cadmium selenide (CdSe), a binary II-VI semiconductor, enjoys great potential in the application of Si-based tandem solar cells because of the suitable bandgap of ~1.7 eV, excellent optoelectronic properties, high stability, and low manufacturing cost. Nevertheless, the progress of CdSe thin-film solar cells stays 30 years ago, and there are few systematic studies on CdSe thin-film solar cells in recent years.

Professor Tang Jiang and his team proposed a method of rapid thermal evaporation (RTE) to obtain high-quality CdSe thin films and designed CdSe thin-film solar cells. This study entitled “Rapid thermal evaporation for cadmium selenide thin-film solar cells” was published in Frontiers of Optoelectronics on Dec. 6, 2021.

In this study, the RTE was employed to deposit CdSe thin films, which demonstrate high crystal quality with large grain size and preferred crystal orientation. Meanwhile, the sharp absorption edge at 720 nm indicates CdSe thin film with a direct bandgap of 1.72 eV. The strong photoluminescence with full width at half maximum of 23 nm reveals the CdSe thin films with relatively few defects. Based on the high-quality CdSe thin films, suitable electron transport layer (ETL) and hole transport layer (HTL) were introduced to construct CdSe solar cells. Finally, an efficiency of 1.88% was achieved by designing an optimal configuration of FTO/ZnO/CdS/CdSe/PEDOT/CuI.

This study developed, for the first time, a RTE method to deposit CdSe thin films and provided a systematical characterization of the optoelectric properties. Also, it demonstrated general rules for device design and optimization for CdSe solar cells. It also pointed out the advantages of CdSe thin film and its solar cells. In the future, CdSe solar cells are of high potential in Si-based tandem applications, which is worthy of further study.


Reference: Kanghua LI, Xuetian LIN, Boxiang SONG, Rokas KONDROTAS, Chong WANG, Yue LU, Xuke YANG, Chao CHEN, Jiang TANG. Rapid thermal evaporation for cadmium selenide thin-film solar cells. Front. Optoelectron., 2021, 14(4): 482‒490


About Higher Education Press

Founded in May 1954, Higher Education Press Limited Company (HEP), affiliated with the Ministry of Education, is one of the earliest institutions committed to educational publishing after the establishment of P. R. China in 1949. After striving for six decades, HEP has developed into a major comprehensive publisher, with products in various forms and at different levels. Both for import and export, HEP has been striving to fill in the gap of domestic and foreign markets and meet the demand of global customers by collaborating with more than 200 partners throughout the world and selling products and services in 32 languages globally. Now, HEP ranks among China's top publishers in terms of copyright export volume and the world's top 50 largest publishing enterprises in terms of comprehensive strength.

The Frontiers Journals series published by HEP includes 28 English academic journals, covering the largest academic fields in China at present. Among the series, 13 have been indexed by SCI, 6 by EI, 2 by MEDLINE, 1 by A&HCI. HEP's academic monographs have won about 300 different kinds of publishing funds and awards both at home and abroad.


About Frontiers of Optoelectronics

Frontiers of Optoelectronics (FOE) aims at introducing the most recent research results and the cutting edge improvements in the area of photonics and optoelectronics. It is dedicated to be an important information platform for rapid communication and exchange between researchers in the related areas. The journal publishes review articles, research articles, letters, comments, special issues, and so on. The Editors-in-Chief are Academician Qihuang Gong from Peking University and Prof. Xinliang Zhang from Huazhong University of Science and Technology. FOE has been indexed by ESCI, Ei, SCOPUS, CSCD, Source Journals for Chinese Scientific and Technical Papers and Citations, etc. FOE will be fully open access since 2022.

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