One-dimensional lead iodide hybrid stabilized by inorganic hexarhenium cluster cations as a new broad-band emitter

A novel one-dimensional (1D) hybrid {[Re₆S₈(PzH)₆][Pb₃I₈(DMF)₂]}·6(DMF) with hexarhenium cluster cations has been synthesized and characterized by means of single-crystal X-ray diffraction. Two DMF oxygen atoms bridge three lead iodides to form a set of lead iodides, {[PbI_4/2I(O_DMF)_1/2][PbI_4/2(O_DMF)_2/2][PbI_4/2I(O_DMF)_1/2]}^2-, and these sets of lead iodide share edges to form a 1D lead iodide chain, [Pb₃I₈(DMF)₂]^2- which has never been reported before and is different from the typical edge sharing of octahedral PbI₆ units. 1D lead iodide chains are stacked along the a axis, and [Re₆S₈(PzH)₆]²⁺ cations with H-bonded DMF molecules to pyrazole N-H reside between 1D lead iodide chains. This 1D lead iodide hybrid shows strong broad-band emission with a peak at 634 nm. The excellent photoluminescent properties of the new lead iodide hybrid exhibit great potential for optoelectronic applications in photonic devices with broad-band emission and stability. This study introduces a new class of lead iodide hybrid compounds having new inorganic cluster cations rather than the organic amine cations that have been used in numerous studies to date. This work opens a promising path to overcome the instability of perovskites including of organic amine cations.