Chimie Théorique Inorganique

Supervisory authorities


Home > Research > Materials For Energy (and information)

Hybrid organic-inorganic halide perovskites

published on , updated on

Hybrid perovskites have become a “hot topic” in the last few years, primarily due to their undeniable breakthrough in photovoltaic research and development. Currently, the most popular hybrid organic-inorganic perovskites (HOP) are methylammonium (CH3NH3+) lead-halide perovskites. They belong to a class of three-dimensional (3D) crystals of general formula AMX3, where A is a cation, M a smaller cation and X a halogen anion. In the case of (HOP), A is an organic cation and M is a divalent metal cation (e.g. Pb2+). Depending on the choice of the metal, the anion or the organic cation, HOP can crystallize in many different structures. In particular, the structure is sensitive to the size of the organic cation. For ‘large enough’ molecular cations (e.g. C4H9NH3+), the crystal has a two-dimensional (2D) structure with an organic layer buffering inorganic slabs. Therefore, HOP offer an impressive range of structures and, as a consequence, properties accessible through chemical engineering.

Hybrid organic-inorganic halide perovskites
Hybrid organic-inorganic halide perovskites
(a) View of the 3D hybrid organic-inorganic perovskite CH3NH3PbI3 in a cubic structure. (b) Fermi surface in the first Brillouin zone.

Intense investigations on HOP started more than two decades ago when Mitzi and coworkers designed thin-film transistors based on 2D HOP. Since the pioneer work of Miyasaka in 2009 [A. Kojima et al., J. Am. Chem. Soc. 2009, 131, 6050], 3D HOP have become the new superstar of photovoltaics with solar-to-electricity conversion efficiency records that went from 3.8% to over 20% [H. Zhou et al., Science 2014, 345, 542].

Towards a perovskite-based spintronics?
Towards a perovskite-based spintronics?
Scheme of a HOP-based spin-FET taking advantage of the Rashba effect.

Our joint work with FOTON (INSA Rennes) aims at rationalizing the fundamental properties of such HOP in connection to issues of direct relevance to applications. We use concepts of solid-state chemistry and physics, making particular use of symmetry analysis, to inspect electronic, optical and transport properties of such hybrids. As we have demonstrate, spin-orbit coupling plays a dramatic role in the properties of the HOP’s superstar material, which has been further rationalized for other metals as well as for effect of halide substitution. Combined to symmetries, we have shown that it also opens new perspectives in spintronics (Rasba-Dresselhaus effects). Besides, we have developed tools to investigate thoroughly quantum and dielectric confinement, which have been applied to HOP but also to CdSe colloidal nanoplatelets. Building on the NMR expertise available at ISCR, we also conduct in-depth analysis of structural properties.

Selected publications

  • Importance of Spin-Orbit Coupling in Hybrid Organic/Inorganic Perovskites for Photovoltaic Applications
    J. Even, L. Pedesseau, J.-M. Jancu, C. Katan
    J. Phys. Chem. Lett. 2013, 4, 2999
  • Analysis of Multivalley and Multibandgap Absorption and Enhancement of Free Carriers Related to Exciton Screening in Hybrid Perovskites
    J. Even, L. Pedesseau, C. Katan
    J. Phys. Chem. C 2014, 118, 11566