Title : Enzyme sulphide coupling for light induced water splitting and CO2 reduction

Abstract:

Many sulphide semiconductors are photocatalytically active in significant ranges of the visible spectrum; our group has shown this, specifically, for In₂S₃ and SnS₂ (R. Lucena et al., Catal. Commun. 2012, 20, 1; ibid. Appl. Catal. A: General, 2012, 415-416, 111). Furthermore, by including V in these sulphides we have shown how their photocatalytic activities can be further extended to even the NIR range (P. Wahnón et al., Phys. Chem. Chem. Phys. 2011, 13, 20401; R. Lucena et al., J. Mater. Chem. A 2014, 2, 8236). Here we will show how coupling these sulphides with enzymes of hydrogenase or laccase types allow photoevolving H₂ or O₂.

First, we could show that combining In₂S₃ with a hydrogenase it was possible to generate photocatalytically H₂ in presence of a sacrificial agent (C. Tapia et al., ACS Catalysis 2016, 6, 5691). Then, we showed that combining In₂S₃ with a laccase it was possible to generate O₂ photoelectrochemically (C. Tapia et al., ACS Catalysis 2017, 17, 4881), this being the first time that such enzyme-sulphide combination allowed photoevolution of O₂. A similar photoelectochemical generation of O₂ could be shown by combining SnS₂ with a laccase enzyme (C. Jarne et al., ChemElectroChem 2019, 9, 2755).

Some of us carried out recently work which coupled an electrode with a formate dehydrogenase enzyme, including W as active species, so that it was possible to reduce electrocatalytically CO₂ to formate (J. Álvarez-Malmagro et al., ACS Appl. Mater. Interfaces 2021, 13, 11891). Ongoing work will be shown here in which combining this latter enzyme with In₂S₃ nanoparticles allows to perform the same task photocatalytically

Biography:

J.C. Conesa entered the ICP staff in 1979. He was ICP Director in 2014-2018, and is now Ad Honorem Professor in ICP. He was first in Spain using synchrotron radiation to study heterogeneous catalysis; also first in CSIC using quantum calculations to understand them. Active in XPS and FTIR (including operando), EPR and UV-Vis-NIR spectroscopies. He worked on CeO₂-supported metals/oxides for H₂ production, keeping always interest in photocatalysis. He belongs to the Steering Committee of AMPEA, a JP of the European EERA for sustainable energy. His >200 articles and book chapters received about 10000 citations, producing a Hirsch index h=57.