1. Department of Chemistry, University of North Bengal, Darjeeling, West Bengal – 734013, India
2. Centre for Nanotechnology, Indian Institute of Technology Guwahati, Assam – 781039, India
3. Department of Chemistry, Indian Institute of Technology Guwahati, Assam – 781039, India
4. Assam Energy Institute (Centre of Rajiv Gandhi Institute of Petroleum Technology), Sivasagar, Assam – 785697, India