Recently, the research group of researcher Min Jie of the Institute for Advanced Study of Wuhan University has developed ternary high-performance indoor organic photovoltaic devices (IOPVs) based on environmentally friendly solvents, which has made important progress in the research of indoor photovoltaic multi-scenario applications.
The research results, titled “High-Performance Organic Photovoltaic Modules Using Eco-Friendly Solvents for Various Indoor Application Scenarios,” were published in the journal Joule on July 31, 2022. The corresponding author of the paper is Min Jie; The first author is Wu Qiang, Yu Yue.
With the rise of the Internet of Things (IoT) ecosystem, tens of billions of independent, low-power indoor electronic devices require large amounts of off-grid power. Currently, IoT devices are primarily powered by traditional chemical batteries and commercial electricity. However, this type of energy needs to be replaced frequently or maintained regularly, and the way of use is relatively cumbersome and environmentally friendly. In recent years, indoor organic photovoltaics (IOPVs) can be used as a device to convert indoor light into electrical energy due to their high extinction coefficient and band gap adjustability, as well as good indoor low light intensity matching, which can become an ideal green energy source in the IoT ecosystem. The development of IOPVs applications has brought new opportunities, but also great challenges. For example, how to further improve the energy conversion efficiency (PCE) of IOPVs and achieve their green preparation; How to further broaden the application scenarios of IOPVs devices and realize their multi-functional applications.
In view of this, Min Jie’s research group constructed a ternary system with a higher open circuit voltage (VOC) by introducing the wideband non-fullerene acceptor material BTA1 in the J52-Cl:BTA3 binary photovoltaic system, and prepared a green and efficient indoor organic photovoltaic device. Under AM 1.5G (1 standard solar) condition, the ternary blending system (J52-Cl:BTA3:BTA1) obtained 11.22% PCE and exhibited a VOC of 1.28 V. Through the study of relevant physical mechanisms and microscopic morphology, the results show that the addition of BTA1 makes the intermolecular accumulation in the active layer more compact, the crystallinity is better, and the vertical domain size is significantly increased, which effectively improves charge transmission and charge extraction, inhibits non-radiative charge recombination, and thus achieves high VOC and high filling factor (FF). In addition, under the condition of LED indoor light source (2700K, 1000 lux), the IOPV device prepared by the ternary system of tetrahydrofuran processing exhibits 28.84% PCE, which is much higher than that of the binary system (26.66%). At the same time, opaque and translucent photovoltaic modules based on ternary systems (12 cm2) also show good indoor photovoltaic performance (21.98% and 14.77%, respectively, the highest recorded values of IOPVs modules reported so far), and have excellent working stability. Further research has found that such components not only have excellent working stability, but also can effectively drive digital temperature and humidity sensors. Finally, Min Jie’s group also found that the three components can exhibit organic light-emitting diode characteristics, with an internal quantum efficiency of 0.04% and a maximum brightness of nearly 100 cd m-2.
Figure 1: Schematic diagram of the performance of green and efficient indoor organic photovoltaic devices and their functional applications
The study shows that the designed ternary photovoltaic system has great potential in indoor multi-functional integrated applications, and has certain guiding significance for the design and construction of indoor organic photovoltaic materials and photovoltaic systems. The work has been funded by the National Natural Science Foundation of China and the university’s independent scientific research project funds, and has received support and assistance from researchers such as Tuesday Jun of the National Nano Center, Professor Lu Xinhui of the University of Chinese of Hong Kong, and Associate Professor Xie Guohua of the School of Chemistry of Wuhan University in photovoltaic materials and performance characterization. (Source: Science Network)
Related paper information:https://doi.org/10.1016/j.joule.2022.07.001