Unraveling Sunlight by Transparent Organic Semiconductors toward Photovoltaic and Photosynthesis
Yuqiang Liu,†,‡ Pei Cheng,* ,† Tengfei Li,∥ Rui Wang,† Yaowen Li,§ Sheng-Yung Chang,† Yuan Zhu,†Hao-Wen Cheng,†,⊥ Kung-Hwa Wei,⊥Xiaowei Zhan,∥ Baoquan Sun,*,‡ and Yang Yang* ,†
† Department of Materials Science and Engineering, University of California, Los Angeles, California 90095, United States
‡ Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano & Soft Materials(FUNSOM), Joint International Research Laboratory of Carbon-Based Functional Materials and Devicesand § Laboratory of Advanced Optoelectronic Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
∥ Department of Materials Science and Engineering, College of Engineering, Key Laboratory of Polymer Chemistry and Physics ofMinistry of Education, Peking University, Beijing 100871, China
⊥ Department of Materials Science and Engineering, Center for Emergent Functional Matter Science, National Chiao TungUniversity, Hsinchu 30050, Taiwan
Because the visible and the infrared (IR) regions take up ∼47% and ∼51% of the energy in the solar spectrum (AM 1.5G standard), respectively, utilizing the visible light for plant growth and the IR light for power generation is potentially extremely exciting. IR-absorbing organic semiconductors, with localized IR absorption and visible-light transmittance, would be promising materials for this purpose. Here, flexible transparent organic photovoltaics (TOPVs) based on IR-absorbing organic materials were proposed, which can be a simple, low-cost, and promising way to utilize the IR light for electricity generation, and the penetrated visible light will be utilized for photosynthesis in plants. A power-conversion efficiency of ∼10% with an average visible transmittance of 34% was achieved for TOPV devices. Meanwhile, the side-by-side comparison showed that plants grown under the TOPVs filtered light, and those under normal sunlight yielded very similar results. These outcomes demonstrated the results from TOPV devices beyond simple photovoltaic applications.