title: Infra-red photoresponse of mesoscopic NiO-based solar cells sensitized with PbS quantum dot.
abstract: Sensitized NiO based photocathode is a new field of investigation with increasing scientific interest in relation with the development of tandem dye-sensitized solar cells (photovoltaic) and dye-sensitized photoelectrosynthetic cells (solar fuel). We demonstrate herein that PbS quantum dots (QDs) represent promising inorganic sensitizers for NiO-based quantum dot-sensitized solar cells (QDSSCs). The solar cell sensitized with PbS quantum dot exhibits significantly higher photoconversion efficiency than solar cells sensitized with a classical and efficient molecular sensitizer (P1 dye = 4-(Bis-{4-[5-(2,2-dicyano-vinyl)-thiophene-2-yl]-phenyl}-amino)-benzoic acid). Furthermore, the system features an IPCE (Incident Photon-to-Current Efficiency) spectrum that spreads into the infra-red region, reaching operating wavelengths of 950 nm. The QDSSC photoelectrochemical device works with the complexes tris(4,4'-ditert-butyl-2,2'-bipyridine)cobalt(III/II) redox mediators, underscoring the formation of a long-lived charge-separated state. The electrochemical impedance spectrocopy measurements are consistent with a high packing of the QDs upon the NiO surface, the high density of which limits the access of the electrolyte and results in favorable light absorption cross-sections and a significant hole lifetime. These notable results highlight the potential of NiO-based photocathodes sensitized with quantum dots for accessing and exploiting the low-energy part of the solar spectrum in photovoltaic and photocatalysis applications.
authors.affiliation: CEISAM, Chimie Et Interdisciplinarité, Synthèse, Analyse, Modélisation CNRS, UMR CNRS 6230, UFR des Sciences et des Techniques 2, rue de la Houssinière-BP 92208; 44322 NANTES Cedex 3 France.
authors.forename: Mahfoudh
authors.initials: M
authors.lastname: Raissi
authors.affiliation: CEISAM, Chimie Et Interdisciplinarité, Synthèse, Analyse, Modélisation CNRS, UMR CNRS 6230, UFR des Sciences et des Techniques 2, rue de la Houssinière-BP 92208; 44322 NANTES Cedex 3 France.
authors.forename: Yann
authors.initials: Y
authors.lastname: Pellegrin
authors.affiliation: Institut des Matériaux Jean Rouxel, Université de Nantes, CNRS, 2, rue de la Houssinière, BP 32229, 44322 Nantes cedex 03, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Jobic
authors.affiliation: CEISAM, Chimie Et Interdisciplinarité, Synthèse, Analyse, Modélisation CNRS, UMR CNRS 6230, UFR des Sciences et des Techniques 2, rue de la Houssinière-BP 92208; 44322 NANTES Cedex 3 France.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Boujtita
authors.affiliation: CEISAM, Chimie Et Interdisciplinarité, Synthèse, Analyse, Modélisation CNRS, UMR CNRS 6230, UFR des Sciences et des Techniques 2, rue de la Houssinière-BP 92208; 44322 NANTES Cedex 3 France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Odobel