CdS/TiO2 nano hybrid heterostructured materials for superior hydrogen production and gas sensor applications. (15th August 2023)

• Record Type: Journal Article
• Authors: Navakoteswara Rao, Vempuluru; Kedhareswara Sairam, Pasupuleti; Kim, Moon-Deock; Rezakazemi, Mashallah; Aminabhavi, Tejraj M.; Ahn, Chi Won; Yang, Jun-Mo
• Is Part Of: Journal of environmental management. Volume 340(2023)
• Publication Date: 2023-08-15
• Subjects: Heterostructures -- Photocatalyst -- Energy -- Hydrogen; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2023.117895
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: In efforts to minimize environmental pollution and carbon-based gas emissions, photocatalytic hydrogen production and sensing applications at ambient temperature are important. This research reports on the development of new 0D/1D materials based on TiO2 nanoparticles grown onto CdS hetersturctured nanorods via two-stage facile synthesis. The titanate nanoparticles when loaded onto CdS surfaces at an optimized concentration (20 mM), exhibited superior photocatalytic hydrogen production (21.4 mmol/h/gcat ). The optimized nanohybrid was recycled for 6 cycles up to 4 h, indicating its excellent stabity for a prolonged period. Also, the photoelectrochemical water oxidation in alkaline medium was investigated to offer the optimized CRT-2 composite with 1.91 mA/cm 2 @0.8 V vs. RHE (0 V vs. Ag/AgCl) that was used for effective room-temperature NO2 gas detection exhibiting a higher response (69.16%) to NO2 (100 ppm) at room temperature at the lowest detection limit of ∼118 ppb than the pristine counterparts. Further, NO2 gas sensing performance of CRT-2 sensor was increased using UV light (365 nm) activation energy. Under the UV light, the sensor exhibited a remarkable gas sensing response quick response/recovery times (68/74), excellent long-term cycling stability, and significant selectivity to NO2 gas. Due to high porosity and surface area values of CdS (5.3), TiO2 (35.5), and CRT-2 (71.5 m 2 /g), excellent photocatalytic H2 production and gas sensing of CRT-2 is ascribed to morphology, synergistic effect, improved charge generation, and separation. Overall, 1D/0D CdS@TiO2 is proved to be an efficient material for hydrogen production and gas detection. Graphical abstract: Image 1 Highlights: CdS/TiO2 heterostructured nanohybrids showed high H2 efficiency-21.4 mmol/h/gcat . CRT-2 had high response (69.16%) to NO2 (100 ppm) at detection limit of ∼118 ppb. NO2 sensing of CRT-2 was high under UV and visible light (144.5 and 85.9%). The nanohybrids have excellent stability for a long lifetime.