Abstract
On-demand selective photocontrol of electronic materials remains a holy grail of photochemistry. One approach to such control is through selective stimulation of materials’ vibrational dynamics — vibrational control (VC). The phenomenon of electron-phonon interaction opens up an attractive practical applicability of VC: driving complex ultrafast chemical reactions with ultrafast pulses of infrared (IR) light and controlling excitations in photovoltaic materials. However, demonstrations of VC remains scarce in the literature and are only available for a limited range of solution-based model systems to study fundamental properties available via other spectroscopy techniques/modelling. In this work we developed a novel spectroscopy allowing VC in a broad range of optoelectronic materials including metal-halide perovskites (MHPs), photosensitive asymmetric nanogaps (PANs), organic single crystals, and organic photovoltaic blends. This spectroscopy is called photocurrent/photoluminescent vibrationally promoted electronic resonance spectroscopy (PC/PL VIPER, see Fig.1).II By applying PC/PL VIPER, we were able to untangle the complex dynamical picture of organic cation–inorganic framework coupling in MHPs, which appears to arise from stochastic sticking and unsticking of organic cations, mediated by cation–halide hydrogen bonding. We revealed symmetry breaking phenomena in organic rubrene single crystals. And finally, we achieved real VC control altering the photoexcitation path in a P3HT/O-IDFBR blend.