Hyderabad: In a significant step towards sustainable electronics, researchers in India have developed a novel lead-free and environmentally friendly photodetector that operates without external power and delivers stable, long-term performance. The innovation opens new possibilities for applications in consumer electronics, industrial monitoring, security systems, smart wearables and biomedical imaging.
The breakthrough has been achieved by scientists at the International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Hyderabad—an autonomous institute under the Department of Science and Technology (DST)—in collaboration with the Indian Institute of Technology (IIT) Hyderabad. The findings have been published in the journal Solar Energy (Elsevier).
Photodetectors are crucial components in modern cameras, environmental sensors and imaging systems as they convert light into electrical signals. However, many high-performance devices currently rely on lead-based perovskites, which pose environmental and health risks due to their toxicity and also suffer from stability issues under real-world conditions.
To overcome these challenges, the Indian team developed a device based on the lead-free double perovskite material Cs₂AgBiBr₆. The new photodetector shows strong responsiveness to visible light and excellent operational stability while avoiding toxic elements.
A major highlight of the work is its simple and low-cost fabrication process. Unlike conventional photodetectors that require expensive metal contacts, additional hole-transport layers and controlled environments such as gloveboxes or vacuum systems, the new device is hole-transport-material (HTM)-free and uses low-cost carbon electrodes. It is fabricated entirely at room temperature through a single-step coating process under ambient conditions.
The device architecture enables efficient charge separation, allowing it to operate in a self-powered mode without any external voltage. Performance tests demonstrated reliable ON-OFF switching behaviour and high stability. Notably, the photodetector retained more than 90 per cent of its performance even after 60 days of storage under normal room conditions (25–35°C and 35–50 per cent relative humidity), confirming its long-term environmental stability.
Researchers said this combination of eco-friendly materials, low-cost components, simple fabrication and robust performance makes the technology a strong candidate for widespread adoption in electronics and sensing applications. The development also aligns with India’s goals of promoting sustainable materials, green manufacturing and self-reliance in advanced electronic technologies. The study was supported by the Department of Science and Technology, Government of India.
