Solar cell and perovskites
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. 



photo of Dr. Max Karlsson

Double awarded thesis in a highly relevant topic

Max Karlsson, who obtained his PhD from the Department of physics, chemistry and biology at Linköping University, has been doubly recognised for his thesis on the dynamics of blue-emitting metal halide perovskites for light-emitting diodes.

Glowing sheet of glass.

Breakthrough for next-generation digital displays

Researchers at LiU have developed a digital display screen where the LEDs themselves react to touch, light, fingerprints and the user’s pulse, among other things. Their results could be the start of a whole new generation of digital displays.

Sign of Linköping University.

Two new Wallenberg Scholars at LiU

Researchers Feng Gao and Daniel Västfjäll at LiU have been appointed as new Wallenberg Scholars. In addition, six LiU researchers will have their  scholar periods extended. Each researcher receives between SEK 18 and 20 million for five years.


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 devises

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


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).



Miguel A. Torre Cachafeiro, Naresh Kumar Kumawat, Feng Gao, Wolfgang Tress (2024) Pulsed operation of perovskite LEDs: a study on the role of mobile ions NATIONAL SCIENCE REVIEW Continue to DOI
Kang Wang, Jeong Hui Kim, Jie Yang, Xiaoke Liu, Yixuan Dou, Yuxuan Li, Weijian Tao, Haiyun Dong, Haiming Zhu, Kaifeng Wu, Li Na Quan, Feng Gao, Jianpu Wang, Letian Dou, Yong Sheng Zhao (2024) Luminescent metal-halide perovskites: fundamentals, synthesis, and light-emitting devices Science in China Series B: Chemistry, Vol. 67, p. 1776-1838 Continue to DOI
Yu Wang, Feng Wang, Jiaxing Song, Jingchuan Ye, Jieying Cao, Xinxing Yin, Zhen Su, Yingzhi Jin, Lin Hu, Han Zuilhof, Zaifang Li, Wensheng Yan, Feng Gao (2024) Ethyl Thioglycolate Assisted Multifunctional Surface Modulation for Efficient and Stable Inverted Perovskite Solar Cells Advanced Functional Materials Continue to DOI
Joakim Argillander, Alvaro Alarcon, Chunxiong Bao, Chaoyang Kuang, Gustavo Lima, Feng Gao, Guilherme B Xavier (2024) Secure quantum random number generation with perovskite photonics QUANTUM COMPUTING, COMMUNICATION, AND SIMULATION IV, Article 129111B Continue to DOI
Xuran Wang, Mingliang Wang, Zilong Zhang, Dong Wei, Shidong Cai, Yuheng Li, Rui Zhang, Liangliang Zhang, Ruidan Zhang, Chenhui Zhu, Xiaozhen Huang, Feng Gao, Peng Gao, Yang Wang, Wei Huang (2024) De Novo Design of Spiro-Type Hole-Transporting Material: Anisotropic Regulation Toward Efficient and Stable Perovskite Solar Cells RESEARCH, Vol. 7, Article 0332 Continue to DOI
Hongling Yu, Feng Gao (2024) Zwitterionic additive for high-performance pure-blue perovskite light-emitting diodes ADVANCED PHOTONICS, Vol. 6, Article 020501 Continue to DOI
Heyong Wang, Antonella Treglia, Munirah D. Albaqami, Feng Gao, Annamaria Petrozza (2024) Tin-Halide Perovskites for Near-Infrared Light-Emitting Diodes ACS Energy Letters Continue to DOI
Weidong Cai, Jiajun Qin, Xinyu Ma, Shun Wang, Muyi Zhang, Tianjun Liu, Tiqiang Pang, Julia Morat, Yuequn Shang, Fuxiang Ji, Shengying Yue, Feng Gao (2024) Multicolor light emission and multifunctional applications in double perovskite-Cs 2 NaInCl 6 by Cu + /Sb 3+co-doping Chemical Engineering Journal, Vol. 489, Article 151212 Continue to DOI
Lei Xu, Sunsun Li, Wenchao Zhao, Yaomeng Xiong, Jinfeng Yu, Jinzhao Qin, Gang Wang, Rui Zhang, Tao Zhang, Zhen Mu, Jingjing Zhao, Yuyang Zhang, Shaoqing Zhang, Vakhobjon Kuvondikov, Erkin Zakhidov, Qiming Peng, Nana Wang, Guichuan Xing, Feng Gao, Jianhui Hou, Wei Huang, Jianpu Wang (2024) The Role of Solution Aggregation Property toward High-Efficiency Non-Fullerene Organic Photovoltaic Cells Advanced Materials Continue to DOI
Shaohui Liu, Zijian Chen, Yingming Liu, Lingjun Wu, Boyuan Wang, Zixuan Wang, Bobin Wu, Xinyu Zhang, Jie Zhang, Mengyun Chen, Hao Huang, Junzhi Ye, Paul K. Chu, Xue-Feng Yu, Lakshminarayana Polavarapu, Robert L. Z. Hoye, Feng Gao, Haitao Zhao (2024) Data-Driven Controlled Synthesis of Oriented Quasi-Spherical CsPbBr3 Perovskite Materials Angewandte Chemie International Edition, Vol. 63 Continue to DOI
Chunxiong Bao, Zhongcheng Yuan, Wenxiao Niu, Jie Yang, Zijian Wang, Tao Yu, Jianpu Wang, Feng Gao (2024) A multifunctional display based on photo-responsive perovskite light-emitting diodes NATURE ELECTRONICS Continue to DOI
Xiyu Luo, Weidong Xu, Guanhaojie Zheng, Sandhya Tammireddy, Qi Wei, Max Karlsson, Zhaojun Zhang, Kangyu Ji, Simon Kahmann, Chunyang Yin, Yatao Zou, Zeyu Zhang, Huaiyu Chen, Lucas A. B. Marcal, Haifeng Zhao, Dongxin Ma, Dongdong Zhang, Yue Lu, Mingjie Li, Carsten Deibel, Samuel D. Stranks, Lian Duan, Jesper Wallentin, Wei Huang, Feng Gao (2024) Effects of local compositional heterogeneity in mixed halide perovskites on blue electroluminescence Matter, Vol. 7 Continue to DOI
Ben Zhang, Weijie Chen, Haiyang Chen, Guang Zeng, Rui Zhang, Hongxiang Li, Yunfei Wang, Xiaodan Gu, Weiwei Sun, Hao Gu, Feng Gao, Yaowen Li, Yongfang Li (2024) Rapid solidification for green-solvent-processed large-area organic solar modules with >16% efficiency Energy & Environmental Science Continue to DOI
Haiyang Chen, Weiwei Sun, Rui Zhang, Yuting Huang, Ben Zhang, Guang Zeng, Junyuan Ding, Weijie Chen, Feng Gao, Yaowen Li, Yongfang Li (2024) Heterogeneous Nucleating Agent for High-Boiling-Point Nonhalogenated Solvent-Processed Organic Solar Cells and Modules Advanced Materials Continue to DOI
Kunpot Mopoung, Weihua Ning, Muyi Zhang, Fuxiang Ji, Kingshuk Mukhuti, Hans Engelkamp, Peter C. M. Christianen, Utkarsh Singh, Johan Klarbring, Sergey Simak, Igor Abrikosov, Feng Gao, Irina Buyanova, Weimin Chen, Yuttapoom Puttisong (2024) Understanding Antiferromagnetic Coupling in Lead-Free Halide Double Perovskite Semiconductors The Journal of Physical Chemistry C, Vol. 128, p. 5313-5320 Continue to DOI


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