We study conductance in a molecular breadboard junction accommodating up to 61 circuits and demonstrate switching between 4 conductance states.

A systematic study of a new hybrid organicinorganic material where the cation has been replaced with imidazolium is presented. Imidazolium lead iodide (ImPI) shares the same stoichiometry of ABX 3 as a perovskite, however, it has a hexagonal structure. This material shows a vastly improved thermal stability as compared to the more popular hybrid perovskite, methyl ammonium lead iodide (MAPI). ImPI also exhibits a dramatic phase stability as compared to MAPI as demonstrated by the variable temperature XRD data (both low temperature and high temperature). In addition to the enhanced thermal robustness, ImPI shows three times better stability than MAPI under ambient conditions. The stability can be attributed to better packing efficiency of the ImPI lattice which in turn depends on the symmetrical and bulkier organic cation, imidazolium. Optoelectronic measurements were also performed and specifically, unlike for MAPI, photoluminescence measurements of ImPI showcased a broad emission over a range of 500 nm to 900 nm which could be attributed to the presence of selftrapped excitons and as such this broad emission holds promise for light emitting device applications.[a] C.

Organic–inorganic hybrid crystals with lead halides as the inorganic moiety are remarkable, in that they show low-dimensional behavior despite their three-dimensional structures. Here, we report on a unique structure, imidazolium lead iodide C3N2H5PbI3 (ImPI), and show that its electronic ground state represents a one-dimensional (1D) solid with carrier motion confined along nanometer-thin corrugated chains formed by face-sharing PbI6 4– octahedrons. ImPI has a very broad photoluminescence (PL) spectrum peaking around 688 nm (1.8 eV) with a width of 173 nm at high temperatures. This PL emission shows a significant red shift of 1.3 eV relative to the excitonic band gap of ImPI at 400 nm (3.1 eV) estimated from PL excitation spectroscopy. These results are compared with measurements on PbI2. Calculations based on the effective-mass theory show that the increased band gap of ImPI originates from quantum confinement, with the PbI6 4– chains acting as 1D quantum wires. Time-resolved and pump intensity-dependent PL studies provide evidence that PL emission arises from self-trapped exciton recombination, a characteristic of 1D systems with easily deformable lattice. This study establishes ImPI as a 1D hybrid semiconductor with a broad emission spectrum with promise for opto-electronic device applications.

CH3NH3PbI3 has been deposited on three different substrates: FTO and two types of TiO2 electron transport layers. It has been evaluated for degradation under UV and visible light, and the phase has also been regenerated by a simple chemical treatment.