A new conformationally symmetrical calix[4]pyrrole based supramolecular systems for liquid crystalline and window layer solar cell applications.

Abstract

A newly symmetrical liquid crystalline compounds (CPB1-CPB4) based on calix[4]pyrrole as a central rigid core were synthesized via esterification reaction. All four compounds exhibit columnar hexagonal phase over a higher mesophase temperature range and stabilized mesophase upto room temperature. The thermal behaviors and optical textures were identified by using differential scanning calorimetry, Polarizing optical microscopyand the molecular organization of the compound in the mesogenic state is confirmed by X-ray diffraction technique. The molecular system based on calix[4]pyrrole core with symmetrical nature exhibited columnar type self-assembly at room temperature. All four supramolecules with different side spacer showed higher thermal stability. Based upon the optimization, compound CPB2 istested in accordance with the optical window layer in thin films solar cell devices. The calix[4]pyrrole functionalized supramolecular liquid crystalline compound based thin films showed suitable transmittance, optical energy band gap together with absorbance and extinction. The linear dependence of current on the voltage demonstrated Ohmic behavior of the CPB2 films. The surface morphology to the developed samples designated nearly uniform deposition of the CPB2 thin films together with grain growth. The findings warrant suitability of the films to implicate these as an eco-friendly optical window layer in thin films based solar cells.