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

LiU researchers on the list of the world’s most cited

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

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 Linköping University, 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.

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

Publications

2026

Nakul Jain, Xiane Li, Mats Fahlman, Olle Inganäs, Koen Vandewal, Feng Gao (2026) Energetic Offset in Organic Solar Cells- Importance, Confusion and Outlook Advanced Materials, Article e17060 (Article in journal) https://dx.doi.org/10.1002/adma.202517060
Meng Ren, Guodong Chen, Haifei Wang, Bowei Li, Yuetian Chen, Jiahao Guo, Yingping Fan, Shaowei Wang, Yanfeng Miao, Feng Gao, Yixin Zhao (2026) Homogenous FACsPbI3 Perovskite Solar Cells Enabled by a Seed-Facilitated Cation Exchange Strategy Advanced Functional Materials (Article in journal) https://dx.doi.org/10.1002/adfm.75628
Dong-Ho Kang, Chun-Sheng Jack Wu, Yun-Sung Jeon, Mirko Prato, Heyong Wang, Feng Wang, Feng Gao, Nam-Gyu Park, Annamaria Petrozza (2026) Oxidant-Assisted Interface Engineering for Enhanced Stability in Lead Halide Perovskite Solar Cells ACS Energy Letters (Article in journal) https://dx.doi.org/10.1021/acsenergylett.6c00507
Carlito S. Ponseca, Mohammed O. Musa, Feng Wang, Ignas Nevinskas, Andrius Arlauskas, Chiara Musumeci, Ali Shuaib, Fatemah Aldousari, Jens Eriksson, Kaibo Zheng, Feng Gao (2026) Defect mediated pulse terahertz emission from thiocyanate-treated hybrid perovskite nanoparticles: role of the orientation of built-in surface electric field Scientific Reports, Vol. 16, Article 11542 (Article in journal) https://dx.doi.org/10.1038/s41598-026-42017-w
Tiefeng Liu, Zesheng Liu, Ihor Sahalianov, Qiao He, Sang Young Jeong, Huotian Zhang, Qifan Li, Chiyuan Yang, Junpeng Ji, Lize Bynens, Wouter Maes, Feng Gao, Han Young Woo, Martin Heeney, Glib Baryshnikov, Mats Fahlman, Simone Fabiano (2026) Counterion-Controlled Photocatalytic Doping of Organic Semiconductors Advanced Materials (Article in journal) https://dx.doi.org/10.1002/adma.72947
Zhencai Li, Zihao Wang, Huotian Zhang, Xuan Ge, Ivan Hung, Bozhao Yin, Fengming Cao, Pritam Banerjee, Tianzhao Xu, Lars R. Jensen, Joerg Jinschek, Morten M. Smedskjaer, Zhehong Gan, Laurent Calvez, Guoping Dong, Jianbei Qiu, Donghong Yu, Feng Gao, Haomiao Zhu, Yuanzheng Yue (2026) White-Light Emission in Zeolitic Imidazolate Framework Glasses Advanced Materials (Article in journal) https://dx.doi.org/10.1002/adma.72968
Yatao Zou, Yuting Xu, Feng Gao, Weidong Xu (2026) Brightening halide perovskite emitters with Lewis basic molecules NATURE REVIEWS MATERIALS (Article, review/survey) https://dx.doi.org/10.1038/s41578-026-00909-3
Cecilia Bruschi, Ihor Sahalianov, Yuri Tanuma, Levani Skhirtladze, Rashid Valiev, Xinyi Cai, Feng Gao, Mikhail Vagin, Yann Lie, Michael Pittelkow, Renee Kroon, Glib Baryshnikov (2026) Diazadioxa[8]circulene - a platform for stable antiaromatic radicals with strong NIR absorption Materials Chemistry Frontiers, Vol. 10, p. 1418-1427 (Article in journal) https://dx.doi.org/10.1039/d6qm00054a
Lingjiao Zhang, Baiquan Liu, Xinyang Lv, Genghui Zhang, Chenglin Li, Wenjing Zhang, Yunfei Ren, Ziming Chen, Meiyu Zhang, Qifan Xue, Zhenyu Yang, Baodan Zhao, Dongfang Yang, Hang Zhou, Feng Gao, Dawei Di, Chuan Liu (2026) Photovoltage-Driven Two-Transistor-One-Diode Perovskite Pixels for In-Cell Optical Sensing Displays Advanced Materials (Article in journal) https://dx.doi.org/10.1002/adma.202522776
Lu Jin, Shaochen Zhang, Jingjing Zhou, Shenglong Chu, Xiaonan Wang, Zihan Yan, Xiaohe Miao, Rui Zhang, Qingqing Liu, Huazheng Li, Jiazhe Xu, Xu Zhang, Ke Zhao, Donger Jin, Yizhou Zhu, Feng Gao, Jingjing Xue, Rui Wang (2026) Suppressing solvent adducts via coordination competition enables scalable perovskite photovoltaics Nature Communications, Vol. 17, Article 1737 (Article in journal) https://dx.doi.org/10.1038/s41467-026-68439-8
Nannan Sun, Sheng Fu, Yunfei Li, Tianshu Ma, Feng Wang, Wentai Ouyang, Bo Feng, Xiaotian Zhu, Zhengbo Cui, Canglang Yao, Wenxiao Zhang, Xiaodong Li, Changlei Wang, Feng Gao, Junfeng Fang (2026) Highly stable all-perovskite tandem solar cells with targeted conversion of tin-lead surfaces Nature Photonics (Article in journal) https://dx.doi.org/10.1038/s41566-025-01815-w
Yanmei He, Xinyi Cai, Rafael B. Araujo, Yibo Wang, Sankaran Ramesh, Junsheng Chen, Muyi Zhang, Tomas Edvinsson, Feng Gao, Tonu Pullerits (2026) Dimensionality-dependent electronic and vibrational dynamics in low-dimensional organic-inorganic tin halides Nature Communications, Vol. 17, Article 758 (Article in journal) https://dx.doi.org/10.1038/s41467-026-68544-8
Yuwei Li, Xiangyu Ou, Shilin Liu, Jingda Zhao, Lu Xue, Chengjun Liu, Bingjian Zhu, Su Yan, Shuo Wang, Ziyu Wei, Sajid Hussain, Wei Lei, Feng Gao, Xiaobao Xu (2026) Multienergy x-ray imaging enabled by unipolar perovskite detector for intelligent substance identification Science Advances, Vol. 12, Article eadz0228 (Article in journal) https://dx.doi.org/10.1126/sciadv.adz0228
Haobo Yuan, Wenxiao Zhang, Feng Wang, Jianhong Xu, Yuyang Hu, Xuemin Guo, Yunfei Li, Bo Feng, Zhengbo Cui, Wen Li, Sheng Fu, Xiaodong Li, Feng Gao, Junfeng Fang (2026) A tin fluoride-free, efficient and durable tin-lead perovskite solar cell Nature Communications, Vol. 17, Article 360 (Article in journal) https://dx.doi.org/10.1038/s41467-025-65445-0
Hailin Yu, Liutao Chen, Jiayu Wang, Chunxiong Bao, Yang Liu, Yuanhao Li, Yating Mo, Yingyue Hu, Nakul Jain, Xi He, Yinghan Wang, Qichao Ran, Cenqi Yan, Zhe Wang, Borong Lin, Yinhua Zhou, Feng Gao, Pei Cheng (2026) Energy-generating smart windows based on reversible metal electrodeposition Materials Horizons, Vol. 13, p. 2052-2059 (Article in journal) https://dx.doi.org/10.1039/d5mh01923k

Coworkers

Two male scientists walks and talks in a hallway. Photographer: Thor Balkhed

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