The development of a visible-light-active photocatalyst for the removal of organic contaminants from water is of primary importance. In this work, we have developed a one-pot synthesis method for visible-light-active aluminum-doped titania (TiO2) with highly efficient sorption degradation of the fluoroquinolone-based pharmaceutical pollutant norfloxacin in aqueous solution. Here, we reduced the effective band gap of TiO2 by in situ doping of aluminum (1 mol %), which significantly improves the porosity, resulting in a high sorption capacity (209 mg/g) toward norfloxacin. The doping of aluminum in TiO2 makes it photocatalytically active in visible light and overcomes the shortcomings of undoped TiO2 in favor of the photodegradation process. 1% aluminum-doped TiO2 (AT) nanoflakes achieves 93% norfloxacin removal (of 2 × 10–4 M) in 2 h with almost 5 times higher rate constants (0.0143 min–1) compared to undoped TiO2 nanoflakes under visible light. Additionally, a high bacterial disinfection activity of doped samples compared to undoped TiO2 in visible light (nearly 80%) as well as in the dark (nearly 20%) was also observed toward both Staphylococcus aureus and Escherichia coli bacteria. The end product of the degradation process was analyzed using mass spectroscopy to determine the mechanistic pathways of the degradation process and the fate of the pollutants. The reusability of the prepared samples was tested and found to be active even after several cycles.

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Crystalline phases along with the morphology of any semiconducting material are the key factors which govern its photocatalytic properties. Herein, we have prepared a composite of α- and δ-MnO2 with...

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The growing world population is closely associated with the increased demand of safe drinking water and sustainable energy production. This drives the focus of the scientific community to work toward water remediation and clean energy generation. The combination of photoelectrooxidation of pollutants at the anode with simultaneous hydrogen gas production at the cathode is a smart strategy to address these problems. Herein, we have designed a bifunctional photoelectrocatalytic system consisting of a self-standing photoanode to degrade the water pollutant molecules with simultaneous production of molecular hydrogen at the cathode. The photoanode was prepared by coating Bi2O3 over the surface of self-standing TiO2 nanorods. Thus, prepared photoelectrodes show high degradation efficiency for rhodamine molecules, where direct oxidation of rhodamine by the holes generated under solar light illumination was detrimental for its activity. During simultaneous pollutant removal and energy production experiments, the anode shows 100% degradation of pollutant molecules while the cathode shows high hydrogen gas production (128 mM cm–2 h–1). The prepared composite showed higher efficiency of visible-light absorbance, high charge generation capability, and low charge transfer resistance at the interface as determined via several characterizations, compared to the bare titania. The catalyst is easy to prepare and robust in activity for several kinds of pollutant molecules tested. Its robust activity, high stability, and durability open up an avenue for the wastewater treatment with simultaneous renewable energy production technologies.

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Intermittent nature of renewable energy led us more to incline over energy conversion and storage. Thus, use of solar radiation towards energy conversion e. g. hydrogen evolution, environmental‐remediation etc. are emerging areas where the materials should be capable of absorbing light energy and transform this absorbed energy into other application. In the present work, the photoelectrochemical and photocatalytic activity of the Ag/TiO2 /RGO catalyst for hydrogen evolution reaction (HER) and methyl orange dye degradation has been reported. Ag/TiO2 /RGO catalyst showed the highest current density for HER which was ca. 2 and 3 times more than Ag NPs and TiO2 nanoflakes, respectively. The interfacial charge transfer between RGO‐TiO2‐Ag hetero‐junction actually improves the charge separation and increases both the photocatalytic activity and hydrogen generation. The composite was also equally capable to degrade environmental pollutant and with the addition of silver, methyl orange dye degradation percentage enhances from 8.9 % (TiO2 nanoflakes) to 81 % (for Ag/TiO2/RGO) with the increment in rate constant from 9.38 X 10−4 (TiO2 nanoflakes) to 1.69×10−2 min−1.