1 Nanomaterials & Solar Energy Conversion Lab, Department of Chemistry, National Institute of Technology, Tiruchirappalli 620015, India.
2 Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
3 Nanomaterials & Solar Energy Conversion Lab, Department of Chemistry, National Institute of Technology, Tiruchirappalli 620015, India. Electronic address: sanand@nitt.edu.