Scientists have developed a new non-toxic material that uses solar energy to degrade harmful synthetic dye pollutants which are released at a rate of nearly 300,000 tonnes a year into the world’s water. The research was published in the journal Scientific Reports.
The novel, non-hazardous photocatalytic material developed researchers at Swansea University in the UK effectively removes dye pollutants from water, adsorbing more than 90% of the dye and enhancing the rate of dye breakdown by almost ten times using visible light.
By heating the reaction mixture at high pressures inside a sealed container, the composite is synthesised by growing ultrathin “nanowires” of tungsten oxide on the surface of tiny particles of tantalum nitride.
As a result of the incredibly small size of the two material components — both the tantalum nitride and tungsten oxide are typically less than 40 billionths of a metre in diameter — the composite provides a huge surface area for dye capture.
The material then proceeds to break the dye down into smaller, harmless molecules using the energy provided by sunlight, in a process known as “photocatalytic degradation.” Having removed the harmful dyes, the catalyst may simply be filtered from the cleaned water and reused.
While photocatalytic degradation of dyes has been investigated for several decades, it is only relatively recently that researchers have developed materials capable of absorbing the visible part of the solar spectrum.
