Optoelectronics

Solar cell and perovskites
Photographer: Olov Planthaber

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

Huotian Zhang

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 , has been awarded the prestigious scholarship from Stiftelsen Konung Carl XVI Gustafs 50-årsfond för vetenskap, teknik och miljö.

Portrait (Feng Gao).

Prestigious physics award for Feng Gao

This year's Göran Gustafsson Prize in Physics goes to LiU professor Feng Gao. His research focuses on how new materials can be used for the next generation of solar cells and LEDs, among other things. The total prize money is SEK 7.5 million.

Researcher hold a glowing sheet of glass with tweezers.

Next generation LEDs are cheap and sustainable

Cost, technical performance and environmental impact – these are the three most important aspects for a new type of LED technology to have a broad commercial impact on society. This has been demonstrated by LiU-researchers in a new study.

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:Y6Organic 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 dotsPerovskite 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 receiverA 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

2025

Xin Liang, Sanwan Liu, Tiankai Zhang, Matthias J. Grotevent, Guiming Fu, Jae-Min Jang, Chae-Yeon Lee, Seong-Ho Cho, Yong Ming, Chandan Chandru Gudal, Sang Yoon Kim, Chan-Hwa Chung, Tae-il Kim, Jun-Yeob Lee, Feng Gao, Moungi G. Bawendi, Nam-Gyu Park (2025) Journal of the American Chemical Society (Article in journal)
Lingzhi Guo, Lunbi Wu, Tao Jia, Huotian Zhang, Jiali Song, Xianqiang Xie, Min Hun Jee, Haisheng Ma, Sha Liu, Guanghao Lu, Han Young Woo, Zhen Wang, Feng Gao, Yanming Sun (2025) Angewandte Chemie International Edition (Article in journal)
Xinyi Liu, Jin Xie, Ziren Zhou, Huijun Lian, Xinyuan Sui, Qing Li, Miaoyu Lin, Da Liu, Haiyang Yuan, Feng Gao, Yongzhen Wu, Hua Gui Yang, Shuang Yang, Yu Hou (2025) NANO-MICRO LETTERS, Vol. 18, Article 67 (Article in journal)
Beibei Shi, Yiyun Li, Jiangkai Sun, Rui Sun, Dongcheng Jiang, Rongkun Zhou, Rui Zhang, Jiawei Qiao, Sai Ho Pun, Jicheng Yi, Xinxin Xia, Peng Lu, Yufei Wang, Guangye Zhang, Tao He, Maojie Zhang, Ziwu Ji, Xiaoyan Du, Jie Min, Feng Chen, Feng Gao, Xiaotao Hao, He Yan, Hang Yin (2025) Advanced Materials, Article e05313 (Article in journal)
Wangxiao Jin, Siyu He, Xiuyuan Lu, Xitong Zhu, Dijiong Liu, Guolong Sun, Yanlei Hao, Zuyan Chen, Chenyang Wang, Jiejun Zeng, Zhi Zheng, Xiaolin Yan, Yiran Yan, Longjia Wu, Xiongfeng Lin, Wenjun Hou, Weiran Cao, Chuan Liu, Xiaoci Liang, Yuan Gao, Yunzhou Deng, Kaisheng Cao, Yingguo Yang, Feng Gao, Yizheng Jin (2025) Nature Photonics (Article in journal)
Kunpot Mopoung, Quanzheng Tao, Fabio Orlandi, Kingshuk Mukhuti, Kilian S. Ramsamoedj, Utkarsh Singh, Sakarn Khamkaeo, Muyi Zhang, Maarten W. de Dreu, Elvina Dilmieva, Emily L. Q. N. Ammerlaan, Thom Ottenbros, Steffen Wiedmann, Andrew T. Boothroyd, Peter C. M. Christianen, Sergey Simak, Johanna Rosén, Feng Gao, Irina Buyanova, Weimin Chen, Yuttapoom Puttisong (2025) Chemistry of Materials (Article in journal)
Lixiu Zhang, Mei Zhang, Hantao Wang, Zhizai Li, Zilong Zhang, Yilong Song, Xin Song, Shurong Wang, Jingxuan Chen, Wenxuan Li, Hua Dong, Feng Wang, Yucheng Liu, Xiaoming Li, Jianyu Yuan, Wanli Ma, Yaohong Zhang, Shengzhong (Frank) Liu, Feng Gao, Zhaoxin Wu, Zhenyu Yang, Feng Hao, Kui Zhao, Zhiwen Jin, Keyou Yan, Jingjing Chang, Jing Cao, Jingjing Wang, Xiaoliang Zhang, Qingfeng Dong, Peng Gao, Yixin Zhao, Lixin Xiao, Yong Ding, Liming Ding (2025) Advanced Materials, Article e12221 (Article, review/survey)
Ruiqin Huang, Longbo Yang, Feng Yang, Yuttapoom Puttisong, Qingsong Hu, Guixian Li, Jingnan Hu, Zhaobo Hu, Liang Li, Jiang Tang, Weimin Chen, Yibo Han, Jiajun Luo, Feng Gao (2025) Nature Communications, Vol. 16, Article 7264 (Article in journal)
Masoud Karimipour, Nil Monros Oliveras, Zhenchuan Tian, Francesco Salutari, Maria Chiara Spadaro, Tiankai Zhang, Naji Vahedigharehchopogh, Jordi Arbiol, Feng Gao, Monica Lira-Cantu (2025) Advanced Science (Article in journal)
Zhigao Huang, Yinjuan Ren, Yiming Wu, Jiajun Qin, Kerong Jiao, Hao Zhang, Van Duong Ta, Feng Gao, Hua Shen, Yue Wang (2025) Advanced Materials (Article in journal)
Meng Cai, Wei Liu, Tiankai Zhang, Pengfei Yan, Yuxuan Li, Weiqian Kong, Hangjuan Wu, Zongwei Chen, Zhenkun Gu, Lin Dong, Qun Xu, Yanlin Song, Junjie Ma, Chongxin Shan, Feng Gao (2025) Advanced Materials (Article in journal)
Heyong Wang, Antonella Treglia, Chun-Sheng Jack Wu, Guanhaojie Zheng, Miguel M. de Vries Ibanez, Gianvito Vile, Hui Li, Luca Gregori, Filippo De Angelis, Jianpu Wang, Feng Gao, Annamaria Petrozza (2025) ACS Energy Letters, Vol. 10, p. 3375-3382 (Article in journal)
Haixia Hu, Rui Zhang, Dongcheng Jiang, Xinyu Mu, Jicheng Yi, Han Yu, Lik-Kuen Ma, Bin Li, Lingxin Cao, Mengzhen Sha, Jiangkai Sun, Ruohua Gui, Wei Liu, Shijie Liang, Longlong Li, Shufen Huang, Jianyu Yuan, Chengwang Niu, Cunquan Qu, Jun Yuan, Rongkun Zhou, Chen Zhang, Lin Lu, Xiaoyan Du, Kun Gao, Weiwei Li, Shu Kong So, Yingping Zou, Yanming Sun, Xiaotao Hao, Feng Gao, He Yan, Hang Yin (2025) Nature Communications, Vol. 16, Article 6546 (Article in journal)
Guangkun Song, Tengfei He, Ruohan Wang, Yanni Ouyang, Nakul Jain, Saisai Liu, Bin Kan, Yujie Shang, Jiaqi Li, Xingkai Wang, Zhaoyang Yao, Xiangjian Wan, Chenxi Li, Wei Ma, Yan Zhao, Guankui Long, Chunfeng Zhang, Feng Gao, Yongsheng Chen (2025) Angewandte Chemie International Edition, Vol. 64, Article e202506357 (Article in journal)
Li Wan, Eunkyung Cho, Rui Zhang, Theis Brock-Nannestad, Zhaohui Wang, Jean-Luc Bredas, Veaceslav Coropceanu, Feng Gao (2025) Advanced Materials (Article in journal)

Coworkers

Two male scientists walks and talks in a hallway. Photographer: Thor Balkhed
Principal research engineer Weihua Ning and professor Feng Gao at the Department of Physics, Chemistry and Biology.

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 Skłodowska-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.

Contact

Organisation