A High-Performing Nanostructured Ir Doped-TiO2 for Efficient Photocatalytic Degradation of Gaseous Toluene

Van Thi Thanh Ho,Ngan Thi Thanh Nguyen,Thi Kim Ngan Tran,Khang Quang Bui,Dung Hung Chau,Long Giang Bach,Son Nguyen Truong

doi:10.3390/inorganics10030029

Abstract

TiO2-based photocatalysts still have some limitations such as large bandgap and low surface area, leading to low efficiency in the photocatalytic degradation of VOCs and limiting it to use in sunlight. Here we report that the nanostructured Ir-doped TiO2 as an efficient photocatalyst generates an excellent risk-reduction material of gaseous toluene. We have succeeded in developing a nanostructured Ir-doped TiO2 and initially found that excellent efficient photocatalytic VOC decomposition can be achieved in our materials The nanostructured Ir-doped TiO2 was synthesized by a one pot, low temperature hydrothermal process with different ratios of Ir doped into the TiO2. It exhibited a high surface area, uniformly spherical morphology of 10–15 nm. Its activity for the photocatalytic degradation of gaseous toluene exhibited up to 97.5% under UV light. This enhancement could be explained by iridium doping which created a high concentration oxygen vacancy and changed the recombination rate of the photogenerated charge carriers. More generally, our study indicates a strategic way to develop the novel nanostructured material for numerous applications.

Highlights

Volatile organic compounds (VOCs) are one of the sources of indoor air pollution, which are highly toxic and adversely affect the health of people by causing headaches, nausea, or allergies [1,2]
The rutile phase in undoped TiO2 was higher as compared to the doped TiO2, which could be explained by the iridium doping process
We found that the toluene degradation efficiency under visible light was 46.25% in 8.5 min compared to the efficiency under UV light of approximately 97% in 8.5 min

Summary

Introduction

Volatile organic compounds (VOCs) are one of the sources of indoor air pollution, which are highly toxic and adversely affect the health of people by causing headaches, nausea, or allergies [1,2]. There have been several methods for the removal of VOCs from indoor air, such as using specific filtrations [3], thermally oxidating [4], or using activated carbon [5] They have some drawbacks such as producing secondary waste, requiring a high temperature, or re-emitting toxic gases to the air when the adsorbents are saturated. Because of these disadvantages, scientists have been developing novel photocatalysts which can degrade VOCs to harmless carbon dioxide and water, while being simple to operate and energy saving. Yadav et al developed a graphitic carbon nitrile (g-C3N4) photocatalyst from melamine via the pyrolysis route to degrade Rhodamine

Objectives

Methods

Results

Conclusion