Photocatalytic recovery of H2 from H2S containing wastewater: Surface and interface control of photo-excitons in Cu2S@TiO2 core-shell nanostructures

Autor: V. Navakoteswara Rao, Muthukonda Venkatakrishnan Shankar, Nagaraj P. Shetti, P. Ravi, M. Mamatha Kumari, Tejraj M. Aminabhavi, N. Lakshmana Reddy, K.M. Kuruvilla, Marappan Sathish, Kakarla Raghava Reddy, V. Preethi
Rok vydání: 2019
Předmět:
Zdroj: Applied Catalysis B: Environmental. 254:174-185
ISSN: 0926-3373
Popis: This study focuses on the synthesis of Cu2S particles as the core wrapped-up with thin layer of TiO2-shell for improved surface and interface control of photo-excitons for H2 production. Chemical states of metal Cu+, Ti4+ ions were confirmed by X-ray Photo-electron and Electron Paramagnetic Resonance (g-factor of 2.03) Spectroscopy. Transmission Electron Microscopic images revealed the hexagonal shape of Cu2S wrapped-up with TiO2 having the shell thickness varying from 12.0 to 16.7 nm. Time resolved transient photoluminescence decay spectra confirmed that three folds prolonged life-time of excitons generated on Cu2S@TiO2 core-shell than pristine Cu2S. The batch photo-ractor used to evaluate the performance of photocatalysts in an aqueous solution containing Na2S/Na2SO4 promoted oxidation reaction for H+ generation. The control over shell thickness directly influenced the optical and surface-interface properties, resulting in the enhanced H2 production of 41.6 mmol h−1 g−1 of catalyst for an optimized catalyst with UV–vis light to H2 production efficiency of 10.3%. The same catalyst also exhibited excellent stability for un-interrupted H2 production upto 30 h, along with good results on recyclability and reusable efficiency. Scale-up operation performed to recover H2 from sulphide wastewater in tank photo-reactor triggered H2 gas 16.1 mmol h−1 g−1 of catalyst.
Databáze: OpenAIRE
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