Heterogeneous Photocatalysis: Recent Advances and Applications

Abstract

Semiconductor heterogeneous photocatalysis, the subject of this review, is a versatile, low-cost and environmentally benign treatment technology for a host of pollutants. These may be of biological, organic and inorganic in origin within water and air. The efficient and successful application of photocatalysis demands that the pollutant, the catalyst and source of illumination are in close proximity or contact with each other. The ability of advanced oxidation technology to remove low levels of persistent organic pollutants as well as microorganisms in water has been widely demonstrated and, progressively, the technology is now being commercialized in many areas of the world including developing nations. This review considers recent developments in the research and application of heterogeneous semiconductor photocatalysis for the treatment of low-level concentrations of pollutants in water and air using titanium dioxide as a "model" semiconductor. The review considers charge transport characteristics on the semiconductor surface, photocatalyst reactor design and organic degradation mechanistic pathways. The effects of photoreactor operating parameters on the photocatalytic process are discussed in addition to mineralization and disinfection kinetics.

Hydrogen Generation through Solar Photocatalytic Processes: A Review of the Configuration and the Properties of Effective Metal-Based Semiconductor Nanomaterials

“…In such a case, charge carriers with increased lifetime can undergo redox reactions and enhance hydrogen generation [58]. Several metal-based nanoparticles with n-p heterojunctions have been recently developed for different photocatalytic applications [59][60][61][62][63][64]. Some of those that have been successfully employed for solar-driven hydrogen generation through water photosplitting are reported in Table 1 [29,58,65].…”

Effect of Calcination Temperature on Performance of Photocatalytic Reactor System for Seawater Pretreatment

“…Photocatalyst are semiconductors that have capabilities to cause or accelerate the chemical reactions upon light absorption notably sunlight [5] can be one of the alternative ways to be use in seawater pre-treatment. Indeed, commercially available photocatalytic water treatment plant using artificial UV-light as the energy source is available and can be considered applied in the photoreaction system [6]. Currently, many researches on water purification using the semiconductor photocatalyst by TiO2 catalyst are carried out.…”

“…TiO2 catalyst becomes well-known in the research field and industrial field. TiO2 catalyst also becomes the important materials in many practical applications and is used as a desiccant, brightener or reactive radiator [6] and also can be applied in energy catalyst (in water splitting to produce hydrogen fuel), an environmental catalyst (in water and air purification) or an electron transport medium (in dye-sensitized solar cells) [7].…”

Au/TiO2-CeO2 Catalysts for Photocatalytic Water Splitting and VOCs Oxidation Reactions

“…During this time, photocatalysis with TiO 2 was applied with various success to several reactions, among them H 2 production by water splitting or abatement of undesired and harmful organic compounds in air or water [2][3][4][5][6][7][8]. The good quantum yield and stability, high oxidative power, low cost and easy production [9][10][11] are the key reasons for the success of TiO 2 .…”