Mo thio and oxo-thio molecular complexes film as self-healing catalyst for photocatalytic hydrogen evolution on 2D materials

Juliana Barros Barbosa (1) , Pierre-Louis Taberna (1) , Valérie Bourdon (2) , I.C. Gerber (3) , Romuald Poteau (3) , Andrea Balocchi (3) , Xavier Marie (3) , Jérôme Esvan (1) , Pascal Puech (4) , Antoine Barnabé (1) , Lucianna da Gama Fernandes Vieira (1) , Ionut-Tudor Moraru (3) , Jean-Yves Chane-Ching (1)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
2 UT3 - Université Toulouse III - Paul Sabatier
3 LPCNO - Laboratoire de physique et chimie des nano-objets
4 CEMES - Centre d'élaboration de matériaux et d'études structurales

2D semiconducting nanosheets of Transition Metal Dichalcogenides are attractive materials for solar energy conversion because of their unique absorption properties. Here, we show that Mo thio- and oxo-thio-complexes anchored on 2D p-WSe2 nanosheets considerably boost water splitting under visible light irradiation with photocurrent density up to 2.0 mA cm−2 at -0.2 V/NHE. Besides developing high electro-catalytic activity, the Mo-complexes film is also shown to be capable of healing surface defects. We propose that the observed healing of surface defects arises from the strong adsorption on point defects of the 2D WSe2 substrate of Mo complexes such as (MoS4)2-, (MoOS3)2-, (Mo2S6O2)2- as supported by DFT calculations. In addition, the thio-, oxo-thio Mo complexes films are shown to enhance charge carrier separation and migration favouring the hydrogen evolution reaction, putting forward the use of thio-, oxo-thio-Mo complexes as a multicomponent passivation layer exhibiting multiple properties.

Mots clés: Hydrogen evolution; Water splitting; 2D TMDC; Thio-Mo complexes; Photocatalysis

Domaines: Matériaux

Juliana Barros Barbosa, Pierre-Louis Taberna, Valérie Bourdon, I.C. Gerber, Romuald Poteau, et al.. Mo thio and oxo-thio molecular complexes film as self-healing catalyst for photocatalytic hydrogen evolution on 2D materials. Applied Catalysis B: Environmental, 2020, 278, pp.119288-119301. ⟨10.1016/j.apcatb.2020.119288⟩. ⟨hal-03031655⟩