Investigation of photocatalytic performance of natural zeolite/TiO ₂ composites

Abstract

The growing increase of industrial wastewater, environmental contaminations, and the necessity of clean water has stressed the importance of removing pollutants. One of the effective means of removing pollutants from water and wastewater is by utilising zeolite. Zeolite, despite possessing unique photophysical properties (such as numerous fine cavities, the high capability to adsorb, and chemical-thermal stability), represents some limitations when being used. Depositing photocatalysts on zeolite particles to improve its removal potential is of much interest. In this work, therefore, TiO 2 nanoparticles were deposited on fine particles of zeolite. Zeolite/TiO 2 composites were evaluated by X-ray diffractometer, scanning electron microscope, Brunauer-Emmett-Teller, diffuse reflectance spectroscopy analyses. The results indicate that the presence of TiO 2 nanoparticles reduces the specific surface area. However, it causes the ability to absorb UV light. Increasing the amount of TiO 2 any further will bring about a redshift in absorption edge. Photocatalytic properties of the composites were assessed by methyl orange and cyanide ion removal examination. The 10%TiO 2 composite with the specific surface area of 34 m 2 /g and bandgap energy of 3.3 eV showed to be the most efficient. The superior photocatalytic performance of 10%TiO 2 sample was confirmed by the examination of producing hydrogen from water/methanol.

Synthesis and characterisation of TiO 2 nanoparticles/Fe 2 O 3 waste chips composite

“…To produce the composites, TiO 2 nanoparticles were synthesised by using chemical method as described in our previous work [4, 10]. In brief, distilled water (85 cc), HCl (6 cc), and 2‐propanol (6 cc) were mixed and stirred together at room temperature.…”

“…Moreover, owing to its relatively high bandgap (3.02-3.2 eV), TiO 2 is excited by UV light, yet UV light constitutes roughly 5% of sunlight. Doping TiO 2 , and compositing it with various materials are two typical and effective means of tackling these problems [2,[7][8][9][10].…”