BRIN Develops Solar Cells from Purple Bacteria
The National Research and Innovation Agency (BRIN) is developing solar cell technology based on photosynthetic pigments from purple bacteria as a renewable energy alternative. The innovation leverages the bacteria’s natural ability to capture sunlight to produce electrical energy.
Tulus, an engineer at BRIN’s Nanotechnology Systems Research Centre, said the research focuses on utilising the reaction centre-light harvesting 1 (RC-LH1) protein complex from the purple bacterium Rhodobacter sphaeroides as a light-absorbing layer in solar cell devices. “These biological materials are combined with various semiconductor layers to generate charge separation when exposed to sunlight,” he stated on Monday (15/6/2026).
According to Tulus, this research presents a new approach in photovoltaic technology development by exploiting the natural photosynthetic system of purple bacteria. Besides being safe to use as they are non-pathogenic, these bacteria possess efficient photosynthetic capabilities. The research team employed a layered electrode structure of indium tin oxide (ITO), zinc oxide (ZnO), and fullerene (C60) as a cathode to collect electrons, while molybdenum oxide and silver layers were used as an anode to collect holes.
“In principle, photosynthesis and photovoltaics share similarities, both utilising solar energy. Photosynthesis converts light energy into chemical energy, whereas photovoltaics convert it into electrical energy,” Tulus explained. He noted that the main advantage of the purple bacteria’s photosynthetic system lies in its high quantum efficiency and excellent charge separation capability. These characteristics make RC-LH1 a potentially valuable biological material for supporting the development of bio-photovoltaic technology.
“Through this research, we are striving to utilise components of purple bacteria photosynthesis as materials to convert light energy into higher-value electrical energy,” he said. The technology developed by BRIN falls under the category of third-generation solar cells, part of the emerging photovoltaics group, specifically bio-solar cells. In addition to using environmentally friendly materials, the technology is processed at low temperatures and utilises abundant natural resources, making it more sustainable compared to conventional technologies.
Tulus said initial research results show promising achievements. The bio-photovoltaic device developed is capable of producing a high open-circuit voltage value for the solid-state bio-photovoltaic category. “To our knowledge, this achievement remains one of the best results in the field of solid-state bio-photovoltaics for the open-circuit voltage parameter. The next challenge is to increase the current generated so that the overall efficiency of the device becomes even higher,” Tulus remarked.
This research is a collaboration between BRIN, the University of Bristol through Prof. Mike Jones, and researchers from Vrije Universiteit Amsterdam. The collaboration aims to develop innovative solar cell designs that can support the transition towards clean and sustainable energy.