Optoelectronics

We are a multidisciplinary team focusing on solution-processed optoelectronic materials and devices, with a passion for both fundamental science and new applications of these materials and devices.

Optoelectronic devices, such as light-emitting diodes (LEDs), solar cells, photodetectors, lasers and optical transmitters and receivers, are an important part in maintaining a sustainable world. The emergence of exceptional solution-processed semiconductors, including organic semiconductors and metal halide perovskites, offers great opportunities for developing new generations of optoelectronic devices that are of high performance, cost-effective, and integrable with other technological systems.

We have developed a worldwide professional network for collaborations and are also actively engaging in collaborations with industry partners.

News

A close up of a person holding a camera.

LiU researchers push the boundaries of organic solar cells

Researchers at LiU have now demonstrated how organic solar cells can become more efficient than previously thought possible. The key is to extend the time that electrons in the material remain excited, which leads to improved performance.

LiU researchers on the list of the world鈥檚 most cited

Researchers from LiU among the world鈥檚 most influential. Clarivate has once again listed those who rank within the top one per cent most cited in their research fields.

Huotian Zhang receives royal scholarship for his solar energy research

For the second year in a row, a researcher at the Division of Optoelectronics at 一本道 University, has been awarded the prestigious scholarship from Stiftelsen Konung Carl XVI Gustafs 50-årsfond för vetenskap, teknik och miljö.

Materials

Organic semiconductors

Organic semiconductors have great potential in low-cost and large-area device applications, benefiting from cheap manufacturing processes such as solution-based roll-to-roll printing.
All device applications previously dominated by inorganic semiconductors have presented opportunities for their organic counterparts. Such applications include solar cells, LEDs, field-effect transistors, lasers, and memory devices.

Metal halide perovskites

Metal halide perovskites have emerged as one of the most popular semiconducting materials since 2009. They have shown unique properties, including:

• Tunable bandgap

• High absorption coefficient

• Broad absorption spectrum

• High charge carrier mobility

• Long charge diffusion lengths

These properties enable metal halide perovskites to be used in a broad range of photovoltaics and other optoelectronic applications.

Lead free perovskites /Lead free metal halides

The state-of-the-art halide perovskites used for high-performance optoelectronic devices contain toxic lead (Pb). It is therefore attractive to develop lead free perovskites or perovskite alike materials with as good properties as the lead containing counterparts. These new materials provide a rich library to investigate fundamental optoelectronic properties and bring about new possibilities to explore the spintronic properties (e.g. when magnetic ions are involved).

Optoelectronic devices

Organic solar cell with the aktive layer Pm6:Y6 Photo credit Olov PlanthaberSolar cells

Solar power is an ideal source for renewable and clean energy. Solar cells are semiconducting devices which can directly convert solar energy into electricity.
The current solar cell market is dominated by silicon-based devices, with just over 2% of global electricity coming from solar in 2019. The emerging solution-processed solar cells based on organic semiconductors and metal halide perovskites have shown great potential to significantly promote the widespread use of the solar cell technology owing to their advantages of both high performance and low cost.

Perovskite quantum dots Photo credit Olov PlanthaberLEDs

Lighting and displays products are vital electric devices in our daily life, which also account for the largest portion of electricity consumption. LEDs are semiconductor light sources, which emit light when current flows through them. LEDs are considered the most promising energy-efficient technologies for lighting and displays.

Metal halide perovskites demonstrate strong photoluminescence and tunable emission colours, making them a promising candidate for the next generation of highly efficient LEDs.

A combined optical transmitter and receiver Photo credit Magnus JohanssonOther devices

Photodetectors and optical receivers are sensors of light, which can convert light signals into electric signals. They have wide applications, such as optical communication and medical/ healthcare instruments.

Lasers are unusual light sources. They emit a very narrow beam of monochromatic light that is amplified and coherent. Lasers have a variety of applications, ranging from precision cutting tools to communications and scientific instruments.

Research and funding

Research

The Optoelectronic group lead by Prof. Gao dedicates its efforts to energy devices, with the ambition to both improve device performance and understand the underlying fundamentals. Their current investigations include organic semiconductors and metal halide perovskites, with research focuses such as:

Fullerene-free organic solar cells (OSCs) (see our Review article in ). We are interested in fundamental working mechanisms of OSCs (e.g. voltage losses in , , and ; at the same time, we also collaborate with our partners to develop OSCs towards practical applications (e.g. indoor applications of OSCs in , and green solvent processing of OSCs in ).
Perovskite solar cells. We focus on developing stable perovskite solar cells and understanding the degradation mechanisms (e.g. stable perovskite solar cells in )
Perovskite LEDs (see our Review article in ). We aim to develop high-performance perovskite LEDs with different colours (e.g. near infrared in and blue in ), understand the mechanisms (e.g. operational mechanisms in Nature Communications, chemical interactions for high-efficiency and stable perovskite LEDs in and ), and explore new applications (e.g. bidirectional optical signal transmission in )
Lead-free perovskites (see our Review article on lead-free double perovskites in ). We focus on new materials development (e.g. iron-doped double perovskites in ) and the understanding of fundamental properties (e.g. self-trapping in double perovskites in ).

Funding

The Optoelectronic Unit is mainly supported by the following funding agencies:

Publications

2026

Apostolis Verykios, Yasemin Torlak, Fangwen Cheng, M茅lissa Crespin, Marinos Tountas, Nikolaos Tzoganakis, Dimitrios K. Giannopoulos, Antigoni Cheilari, Georgios C. Vougioukalakis, Ermioni Polydorou, Zoi Georgiopoulou, Georgios Chatzigiannakis, Ioannis G. Aviziotis, Vassilis Psycharis, Efi-Maria Papia, Vassilios Constantoudis, Anastasia Soultati, Mahmut Kus, Mustafa Ersoz, Emmanuel Kymakis, Alexander Chroneos, Ioannis Karatasios, Feng Gao, Feng Wang, Maria Vasilopoulou (2026) Scientific Reports, Vol. 16, Article 27313 (Article in journal)

Feiyun Zhao, Haifeng Zhao, Zhennan Tian, Aobo Ren, Lechuan Chen, Hengyu Liu, Jun Wu, Kai Shen, Wuyang Ren, Chuang Li, Chunyang Yin, Junsheng Yu, Feng Gao, Sai Bai, Jiang Wu, Yanrong Li (2026) Nature Communications, Vol. 17, Article 8781 (Article in journal)

Tianzhao Xu, Zhencai Li, Jia-Xin Wu, Zihao Wang, Hanmeng Zhang, Huotian Zhang, Lars R. Jensen, Kenji Shinozaki, Feng Gao, Haomiao Zhu, Ivan Hung, Zhehong Gan, Jinjun Ren, Zheng Yin, Ming-Hua Zeng, Yuanzheng Yue (2026) NATIONAL SCIENCE REVIEW, Vol. 13, Article nwag349 (Article in journal)

Spyros Orfanoudakis, Konstantina Yannakopoulou, Julia Morat, Leonidas Tsetseris, Polychronis Tsipas, Stefania Skorda, Alexandros El Sachat, Feng Gao, Athanassios G. Kontos, Thomas Stergiopoulos (2026) Small (Article in journal)

Abhisek Chakraborty, Giulia Lucarelli, Vaibhav Singh, Jie Xu, Zeynab Skafi, Diksha Thakur, Francesco Di Giacomo, Gyanendra Shankar, Emanuele Calabro, Francesca De Rossi, Osbel Almora, Peyman Amiri, Shinji Aramaki, Diego Bagnis, Tomiki Bannai, Christoph J. Brabec, Daniele Braga, Gregory Burwell, Francesca Brunetti, Aldo Di Carlo, Matt Carnie, Luigi Angelo Castriotta, Sergio Castro-Hermosa, Manuela Ciocca, Yong Cui, Janardan Dagar, Bruno Damien, Sergey V. Dayneko, Nutifafa Y. Doumon, Vida Turkovic, Karen Forberich, Marina Freitag, Feng Gao, Giulia Grancini, Zhanglin Guo, Behrang Hamadani, Mike Hayes, Jianhui Hou, Robert L. Z. Hoye, Stephane Jouin, Marko Jost, Petri Karha, Matthias Kauer, Thomas Kirchartz, George Koutsourakis, Shuuji Kuge, Monica Lira-Cantu, Ian Mathews, Morten Madsen, Matthias Auf Der Maur, Tsutomu Miyasaka, David Muller, Shashank Priya, Erin L. Ratcliff, Andrea Reale, Makhsud I. Saidaminov, Frederic Sauvage, Suraj Soman, Zhenchuan Tian, Marko Topic, Antonio Cabas Vidani, Paola Vivo, Kai Wang, Yuming Wang, Zhao-Kui Wang, Konrad Wojciechowski, Uli Wurfel, Xueqing Xu, Mustafa Yasa, Selcuk Yerci, Andrea Zampetti, Kui Zhao, Thomas M. Brown (2026) Nature Energy (Article, review/survey)

Muyi Zhang, Sakarn Khamkaeo, Xinyi Cai, Utkarsh Singh, Pedram Pakmehr, Kunpot Mopoung, Yuxuan Li, Julia Morat, Kirill Chernenko, Antti Kivim盲ki, Wei-Xin Ni, Maths Karlsson, Irina A Buyanova, Weimin Chen, Sergey Simak, Igor A. Abrikosov, Yuttapoom Puttisong, Feng Gao (2026) Physical Review B, Vol. 114, Article 084308 (Article in journal)

Bei Yang, Chunyang Yin, Yuze Lin, Jianhui Hou, Shaoqing Zhang, Zhiguo Zhang, Jun Yuan, Yingping Zou, Feng Liu, Xiaozhang Zhu, Xiaoke Liu, Yahui Liu, Jun Liu, Hongliang Zhong, Xin Guo, Long Ye, Shuixing Li, Hongzheng Chen, Feng Gao (2026) Journal of Materials Chemistry C (Article in journal)

Alice Fappani, Francesca Pallini, Valentina Bellotti, Jayanta Dana, Dhanushi Srinivasan, Tero-Petri Ruoko, Feng Wang, Feng Gao, Luca Beverina (2026) Nanoscale Advances (Article in journal)

Yingjun Chai, Xiangyu Ou, Dingshuo Zhang, Yu Gu, Xi Qin, Ankang Li, Zhicheng Wang, Xudong Hu, Xingliang Dai, Feng Gao, Xiaoming Li (2026) Advanced Materials (Article in journal)

Kanming Shi, Weidong Cai, Jiajun Qin, Lars Ohrstrom, Fanni Juranyi, Feng Gao, Maths Karlsson (2026) Journal of Materials Chemistry C, Vol. 14, p. 13706-13714 (Article in journal)

Chenglong Li, Wei Qu, Deepak Kumar, Naini Jain, Nur Wardina Syahirah binti Mohamad Fadil, Nur Najiha binti Ahmad Rasid, Emannuel Kymakis, Maria Vasilopoulou, Feng Gao, Chunxiong Bao, Peng Gao, Sanjeev Kumar Sharma, Mohammad Khaja Nazeeruddin, Abd. Rashid bin Mohd Yusoff, Haotong Wei (2026) CARBON ENERGY (Article, review/survey)

Huotian Zhang, Jun Yuan, Tong Wang, Yijie Nai, Nurlan Tokmoldin, Wei Liu, Shanchao Ouyang, Rokas Jasiunas, Yiting Liu, Yuxuan Li, Mohammad Saeed Shadabroo, Manasi Pranav, Nakul Jain, Xiaolei Zhang, Veaceslav Coropceanu, Artem A. Bakulin, Sai-Wing Tsang, Vidmantas Gulbinas, Safa Shoaee, Yingping Zou, Dieter Neher, Thomas Kirchartz, Feng Gao (2026) Nature Photonics, Vol. 20, p. 1040-1047 (Article in journal)

Shuohan Cheng, Yong Cui, Yang Xiao, Zhihao Chen, Zheng Zou, Haoyu Yuan, Tao Zhang, Guanlin Wang, Wenye Xu, Ni Yang, Lijiao Ma, Shaoqing Zhang, Feng Gao, Jianhui Hou (2026) Advanced Materials, Vol. 38, Article e73628 (Article in journal)

Wei Liu, Yijie Nai, Huotian Zhang, Xuehong Zhou, Weidi Ma, Chunlong Sun, Muyi Zhang, Chujun Zhang, Beibei Qiu, Long Ye, Feng Gao, Jun Yuan, Yingping Zou (2026) Advanced Materials, Vol. 38, Article e73840 (Article in journal)

Tinghuan Yang, Erxin Zhao, Nan Wu, Xiaoming Chang, Chenqing Tian, Hai-Long Wang, Lu Zhang, Nannan Gu, Ting Nie, Ye Yang, Zheng Zhang, Tianfei Xu, Xin Chen, Shuang Wang, Tianqi Niu, Niansheng Xu, Chuang Ma, Haojin Li, Buyi Yan, Zicheng Ding, Shengzhong (Frank) Liu, Feng Gao, Kui Zhao (2026) Nature, Vol. 654, p. 660-667 (Article in journal)

Coworkers

Two male scientists walks and talks in a hallway.

Group and Supervision

Prof. Feng Gao is deeply involved in both the scientific and career development of his group members. The senior researchers in his group have been awarded the prestigious VR Staring Grant, Marie Sk艂odowska-Curie Individual Fellowship, VINNMER Fellowship.

He also values the exchange of ideas: he has sponsored members of his group in exchanges to Cambridge, Oxford and EPFL, and his group has hosted visiting students and scholars from Cambridge, Zhejiang University, Nanjing University, Nanjing Tech University, Shenzhen University, Queen Mary University of London, and more.

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