Si/SiO2/Al2O3 Supported Growth of CNT Forest for the Production of La/ZnO/CNT Photocatalyst for Hydrogen Production

Materials

Jana Petrů¹  Irshad Ahmad²  Muhammad Yasin Naz²  Shazia Shukrullah²  Bilal Shoukat²  Muhammad Irfan³  Saifur Rahman³  Mabkhoot A. Alsaiari⁴  Stanislaw Legutko⁵ 

[1] Department of Machining, Assembly and Engineering Metrology, VSB Technical University of Ostrava, 17. Listopadu 2172/15 Street, 70833 Ostrava, Czech Republic;Department of Physics, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan;Electrical Engineering Department, College of Engineering, Najran University Saudi Arabia, Najran 11001, Saudi Arabia;Empty Qaurter Research Unit, Chemistry Department, College of Science and Art at Sharurah, Najran University Saudi Arabia, Najran 61441, Saudi Arabia;Faculty of Mechanical Engineering, Poznan University of Technology, 3 Piotrowo Street, 60-965 Poznan, Poland;

关键词: zinc oxide;    carbon nanotube forest;    lanthanum;    photocatalytic activity;    hydrogen production;   

DOI  :  10.3390/ma15093226

来源: DOAJ

【 摘 要 】

The use of ZnO as a photocatalyst with a reduced recombination rate of charge carriers and maximum visible light harvesting remains a challenge for researchers. Herein, we designed and synthesized a unique La/ZnO/CNTs heterojunction system via a sol–gel method to evaluate its photocatalytic performance for hydrogen evolution. A ferrocene powder catalyst was tested for the production of CNT forests over Si/SiO₂/Al₂O₃ substrate. A chemical vapor deposition (CVD) route was followed for the forest growth of CNTs. The La/ZnO/CNTs composite showed improved photocatalytic efficiency towards hydrogen evolution (184.8 mmol/h) in contrast to 10.2 mmol/h of pristine ZnO. The characterization results show that promoted photocatalytic activity over La/ZnO/NTs is attributed to the spatial separation of the charge carriers and extended optical absorption towards the visible light spectrum. The optimum photocatalyst shows a 16 h cycle performance for hydrogen evolution. The H₂ evolution rate under visible light illumination reached 10.2 mmol/h, 145.9 mmol/h and 184.8 mmol/h over ZnO, La/ZnO and La/ZnO/CNTs, respectively. Among the prepared photocatalysts, ZnO showed the lowest H₂ evolution rate due to the fast recombination of electron–hole pairs than heterojunction photocatalysts. This research paves the way for the development of ZnO and CNT-based photocatalysts with a wide optical response and reduced charge carrier recombinations.

【 授权许可】

Unknown