Photocatalytic Water Purification for Drinking Water and Environmental Remediation

We will develop and apply solar photocatalysis for water treatment where standard methods are inappropriate or impossible to apply. The context includes drinking water in low-income countries and antimicrobial resistance.
Over 2 billion people lack access to safe drinking water (WHO), leading to severe health and equality consequences. Biological contaminants in contaminated water can transmit diseases such diarrhoea, cholera, dysentery, typhoid, and polio. Organic contaminants, such as endocrine disruptors (from pesticides or industrial waste) can cause cancers, damage the immune system, disrupt development/reproduction, and cause neurological effects even in trace quantities. As well as drinking water, contaminants such as antibiotics accumulate in swimming pools and can lead to antimicrobial resistant bacteria accumulating in the filters. Photocatalytic water treatment can destroy such contaminants using only freely-available sunlight and the catalyst material. This is particularly applicable to drinking water in rural areas of developing countries and in situ applications for environmental remediation.
Research questions
1. Development of enhanced photocatalytic materials with better visible light harvesting for more efficient use of sunlight
2. Integration of our existing, and later our enhanced, photocatalytic materials as the final step in the filter-based water-treatment system developed by Clean Water Wave for application in Bangladesh and similar countries.
3. Application of our existing, and later our enhanced, photocatalytic materials in swimming pools to destroy AMR-promoting organics introduced via the bathers.
Methodology
Task 1 Materials development: The materials chemistry component will build on expertise within the research group to develop enhanced photocatalytic materials, fully characterise these and demonstrate their efficacy in lab testing conditions. This makes use of LED light sources and model contaminants including visible dyes, UV-absorbing molecules, bacteria and synthetic waste water. The focus will be on enhancing the visible light efficiency to better match sunlight, compared with existing materials. This will be a higher-risk, higher-return component of the project with the potential for transformative new materials, yet the safety net of using our established materials if no improvement is achieved.
Timeline: Months 1-24, in parallel with materials testing (50%).
Task 2 Photocatalytic application: The application of our photocatalytic materials will start initially with materials we have prepared through previous students and gradually incorporate the new, enhanced materials from Task 1 as they become available. Cooperation with Clean Water Wave will facilitate field trials in Bangladesh and also testing in swimming pools.
Very limited real-world studies have been carried out in this topic and such work, in parallel with new materials development, is essential to progress effective implementation and understanding of a practical working system.
Timeline: Months 1 - 12 focus on swimming pool testing in association with Clean Water Wave as this is easier to facilitate (50%).
Months 13-23 focus on testing in Bangladesh as a component of Clean Water Wave system. This is dependent on arranging in-country field trials so needs a longer lead time to arrange hence starting later (50%).
Months 24-36 will follow up on both these applications flexibly according to initial results. This period will be focused entirely on application of the best materials (100%).
A comprehensive training programme will be provided comprising both specialist scientific training and generic transferable and professional skills.