Ni, C, N, S multi-doped ZrO2 decorated on multi-walled carbon nanotubes for effective solar induced degradation of anionic dye

The present work deals with the synthesisis of Ni, C, N, S mull-doped ZrO2/MWCNT's nanocomposites varying nickel percentage in ZrO2 by homogeneous co-precipitation and fabricated on MWCNT's by ultrasound-assisted hydrothermal method. The nanocomposites were characterized by TEM-SAED, SEM-EDAX, XRD, FT-IR and UV-vis techniques. SEM-EDAX, XRD, FT-IR techniques confirmed Ni, C, N and S doping in ZrO2. The TEM image revealed fabrication of mull-doped ZrO2 nanoparticles on nanotube surface. The nanocomposites employed for photocatalytic degradation of Indigo Carmine anionic dye in eco-friendly solar radiation. Amongst all nanocomposite 1 % nickel concentarion in ZrO2 exhibited much higher photocatalytic degradation efficiency (96 %) as compared with bare ZrO2 (19 %), C,N,S (48 %), 0.3 % (81 %) and 0.6 % (88 %) in 180 min of irradiation at alkaline pH and 3 mgL(-1) catalyst loading following first order rate kinetics (K-a = 16.10 x 10(-3)) by virtue of it lower band gap (4.17 eV) confirmed by UV-vis spectrum. The degradation was confirmed by GC-MS and TOC analysis. Synergism of MWCNT's by electron trapping to generate O-2 center dot- major species confirmed by scavenger addition experiment. The reusability study demonstrated stability and effectiveness of synthesized material for multiple cycles.