Title : Accelerating Photo(electro)Chemical Technology Beyond the Water Splitting Process - Cross Fertilisation of Wastewater Treatment and Green Hydrogen Generation
Green hydrogen – a carbon-free renewable fuel that has the capability to decarbonize a variety of sectors. The generation of green hydrogen is currently restricted to water electrolyzers. The use of freshwater resources and critical raw materials, however, limits its use. Alternative water splitting methods for green hydrogen generation via photocatalysis and photoelectrocatalysis (PEC) has been explored in the past few decades. However, their commercial potential still remains unexploited due to the high hydrogen generation costs. Novel PEC-based simultaneous generation of green hydrogen and wastewater treatment/high value product production is therefore seen as an alternative to conventional water splitting.
Interestingly, the organic/inorganic pollutants in wastewater and biomass favourably act as electron donors and facilitate the dual-functional process of recovering green hydrogen while oxidizing the organic matter. Generation of green hydrogen through the dual-functional PEC process opens up opportunities for a “circular economy”. It further enables the end-of-life commodities to be reused, recycled and resourced for a better life-cycle design while being economically viable for commercialization. This invited talk brings together and critically analyses the recent trends towards simultaneous wastewater treatment/biomass reforming while generating hydrogen gas by employing the PEC technology. We have briefly discussed the technical challenges associated with the tandem PEC process, new avenues, techno-economic feasibility and future direction towards achieving net neutrality.