A copper pipe with water running out of it.

NEW PAPER: Copper photosensitisers for water purification

Congratulations to Grantham Scholar Martin Appleby for being published in the new Royal Society of Chemistry journal, Materials Advances.

Martin’s paper looks at new ways to purify water using copper photosensitisers. If you want to find out more, there’s a summary of the paper below. Or you can skip to the end to find a link to the open access paper.

A quarter of the world drinks dirty water

According to the UN 25% of the global population doesn’t have access to a clean water source. Proper water sanitation could improve this situation.

Unfortunately, many regions lack access to proper water management systems and infrastructure. One way round this would be household water treatments, because they could purify water at point of use. But they would need to be efficient and not use lots of power.

Solar-based water purification

Solar-based water purification using photosensitisers is a possible solution. This process uses the sun’s energy to clean water.

Photosensitisers are molecules that produce chemical changes in other molecules under light. Importantly, they can produce reactive oxygen species. These oxygen species can then kill microorganisms in water.

A wide variety of chemicals have photo-sensitising properties, but transition metal complexes are most commonly used. This is because it is easy to adjust their properties by making small changes to their structure.

Up until now, most metal complexes used have been based on rare transition metals – which makes them pretty expensive.

Copper complex used as photosensitiser

As a result, there has been a search to find a cheap metal that does the job instead. Martin and his team took up this search. Together they have found a way of using copper to create photosynthesising complexes that purify water. By immobilising copper on silica, the team has found a remarkably efficient (“highly protective” according to WHO) way to kill bacteria in water under visible light.

This is the first example of a Cu(i) complex immobilised on silica support as photosensitiser for antibacterial action in water. It demonstrates the potential of Earth-abundant transition metal complexes as low-cost efficient photo-antibacterial agents.

Read this paper for free

Because the paper is open access, you can read it for free.

Follow the link to read online: Cu(i) diimine complexes as immobilised antibacterial photosensitisers operating in water under visible light.

This research took place at the Lord Porter Laser Laboratory at The University of Sheffield.