Synergizing TiO sub(2) Surface to Enhance Photocatalysis: A Green Technology for Clean and Safe Environment - A Review

Photocatalytic removal of pollutants from air and water is a green technology that helps us to maintain a healthy life, clean environment and a balanced ecosystem. Photo-excited TiO sub(2) has strong oxidation ability that can be used to purify indoor air and polluted water. Numerous parameters such as UV light intensity, humidity, substrate concentration, substrate type and O sub(2) partial pressure influence the removal rate of gaseous and/or aqueous contaminants. However, TiO sub(2) photocatalyst cannot decompose large amount of contaminants or refractory chemicals because of the interference in light penetration by the bulk pollutants. Modification of TiO sub(2) surface or combining the TiO sub(2) photocatalyst with other advanced oxidation processes such as sonolysis, ozonization, electrochemical oxidation and photocatalysis could significantly improve the photocatalytic efficiency of TiO sub(2) photocatalyst. This brief review is an up-to-date presentation of the TiO sub(2) surface modification for enhancing its photocatalytic activities for environmental purification.