PolyNanoCat project aimed to investigate the correlation between the photophysical properties and the photocatalytic activity of polymer heterojunction nanoparticles photocatalysts required for a better understanding of the solar-to-fuel mechanism and further provide guidance for the design of efficient photocatalysts. The project was developed in three phases; first donor:acceptor heterojunction nanoparticles were optimized, and their photocatalytic activity and stability for hydrogen evolution under simulated solar irradiation were screened, partnered with our collaborator from the University of Oxford, UK. In parallel, the experimental design and in-depth characterization of the photophysical properties of the best-performing nanoparticles were conducted by using advanced transient absorption and emission spectroscopies on timescales ranging from picoseconds to seconds. Finally, we rationalized the information gained from both photocatalytic and photophysical studies to establish structure-activity relationships for polymer/fullerene and no-fullerene acceptor heterojunction nanoparticles.
The photophysical studies revealed the efficient exciton dissociation at the donor:acceptor heterojunctions within the nanoparticles in picosecond timescale, leading to the accumulation of remarkably long-lived photogenerated charges in millisecond to second timescale, even in the absence of added co-catalyst or sacrificial electron donor. These charges were efficiently extracted upon the addition of the Pt co-catalyst and ascorbic acid as sacrificial electron donor, which suggests that they were responsible for the photocatalytic activity of the nanoparticles.
The project outcomes were disseminated through publications in high-impact peer-reviewed journals, and presentations in national (UK) and international conferences (in EU) by Dr. Gonzalez-Carrero, including invited talks, oral presentations, and poster contributions. In addition, the project was disseminated to non-scientific audiences.
