Bhubaneswar, Oct 28 (UNI) Scientists at the National Institute of Technology (NIT) Rourkela, in collaboration with researchers from IIT Guwahati, IIT Bombay and NISER Bhubaneswar, have developed lead-free light-emitting materials that respond to changes in temperature and moisture, opening up potential applications in anti-counterfeiting technology, humidity sensors and safer lighting systems.