Strategies and insights towards the high performance visible light photocatalytic activity of MnO2/PPy hybrid catalysts: challenges and perspectives

In this work, alpha-MnO(2)on polypyrrole nanosheets (alpha-MnO2/PPy) were constructed via a facile hydrothermal method. The composition of MnO(2)with PPy is varied from 1, 1.5 and 2 mmol %. Tetragonal alpha-MnO(2)phase with spherical particles are uniformly wrapped on the PPy nanosheets, which is determined by XRD, Raman, SEM and TEM analysis. Due to high surface area (104.52 m(2)/g) and porous nature (14.2 nm) of the alpha-MnO2/PPy adsorption edges were further extended with in the visible light region and simultaneous reduction of band gap energy (3.48-2.58 eV) could be observed by UV-Vis spectra. Rapid recombination process of electron-hole process was further diminished the intensity, which is analyzed through PL spectroscopy. The photocatalytic activity of the obtained catalyst was monitored using Reactive Black 31 (RB31) and 4-chlorophenol (2-CP) dyes under visible light. The outstanding degradation efficiency of 96%, high apparent constant (0.8712 min(-1)) and desirable long term stability was observed in MnO2/PPy composite catalyst towards RB31 dye. The improved photocatalytic mechanism has also been proposed.