Hierarchical α-MnO2 wrapped MWCNTs sensor for low level detection of p-nitrophenol in water

Herein, we report a Multi-walled carbon nanotube/manganese dioxide (MWCNTs/MnO2) nanocomposite based electrochemical sensor for micromolar level detection of p - Nitrophenol (p-NP) in aqueous medium. The MWCNTs/MnO2 nanocomposite was synthesized by a two-step process, the pyrolysis growth of MWCNTs followed by solution mediated growth of alpha-MnO2 over MWCNTs. The as-prepared MWCNTs/MnO2 nanocomposite were subjected to structural, morphological and compositional characterizations in order to investigate the nanocomposite formation, surface functionality and other features of the nanocomposite. The electrochemical sensing measurements were then carried out using MWCNTs/MnO2 nanocomposite against p-NP. The sensitivity and limit of detection (LOD) was calculated as 0.186 mu A mu M-1 cm(-2) and 0.644 mu M, respectively. The prepared nanocomposite electrode possess excellent capacity to detect p-NP in wide linear range (30 mu M-475 mu M) with superior anti-interference ability. The developed sensor material (MWCNTs/MnO2) could be useful for the detection of p-NP content in tap water and river water samples.