Flexible Perovskite Solar Cells for Indoor Light Harvesting

Dr Paheli Ghosh (Research Fellow) and Dr Lethy Krishnan Jagadamma (Principal Investigator)

School of Physics and Astronomy
Energy Harvesting Research Group

Solar cells or photovoltaic devices convert the energy of light into electricity by the photovoltaic effect. This project is focused on exploring novel materials and systems for solar cells to harvest light energy from indoor lamps. The primary objective is to tune the bandgap of perovskite semiconductors by compositional engineering for optimising the power output from perovskite solar cells under indoor light conditions. The perovskite-based indoor photovoltaics are high-performing, low-cost, and scalable in nature. They can be fabricated on flexible and wearable substrates such as textiles and plastics and can be used for powering wireless self-powered electronic devices in the Internet of Things.

The image shows the integration of the perovskite solar cells onto flexible substrates such as textiles, plastics and curtains in a ‘stick and remove’ arrangement such that the photovoltaic devices can be used for harvesting the energy from both sunlight and indoor lights, and conversion into electricity. The power generated by these perovskite-based photovoltaic devices can then be used for powering low-power consumption (microwatts to milliwatts) sensors such as light, temperature, humidity, motion, acoustic and chemical sensors in the Internet of Things (IoT). Currently the wireless sensors in the huge technology field of the IoT depend on batteries or grid-based electricity for power input. The complexity of installation processes and environmental repercussions due to the limited lifespan of batteries limit the widespread usage of these sensors. Perovskite semiconductor-based photovoltaic devices combine the useful attributes of high electrical power output, cost-efficiency, scalability, and high specific power (power per unit weight) and show immense prospects for application as indoor photovoltaics, thus, providing partial independence from grid-wired electricity and batteries. The structure of the perovskite solar cells fabricated in our laboratory is also shown with the maximum power conversion efficiency of our devices currently being 27% under indoor light.

Image produced by: Dr Paheli Ghosh and Dr Lethy Krishnan Jagadamma