Bismuth based Panchromatic Solar Light Absorption Complexes Harsh Bhatia, Bob C. Schroeder University College London, UK Bismuth based inorganic materials especially perovskites have explored to a large extent with the applications in the field of photovoltaics and photocatalysts. On the other side, the coordination complexes of bismuth have not been explored and the fundamental photophysical properties of the complexes are poorly understood. However, the complexes of transition metal atoms like Fe, Ru, Pd, Pt, Cu, Au, Ag, Os, Zn, etc. have been the focus of the scientific community for decades to harness solar light and for OLEDs. 1 Such transition metal-based complexes are well studied, however, many of these metal atoms are highly expensive, and toxic which hinders their commercialization to a greater extent. Therefore, it is of umpteen importance to provide the substitute for these metals. In order to overcome these issues herein we report a series phenanthroline (phen) substituted complexes 2 of BiCl 3 , BiBr 3 and BiI 3 The complexes of different coordination number (7 and bi-octahedron) are synthesized and characterized using various spectroscopic tools. The complexes vary by different number and type of halogen(s) as ancillary ligands bound to bismuth (III) centre along with the phen ligand, hence affecting the ground and excited state photophysical properties of the complexes. In this work we present the design strategy to synthesize novel bismuth coordination complexes and study their properties to understand their applications for the solar light absorption and visible light emission. We developed the complexes with different coordination bonds and varying electronic density along the bismuth atom by the change of ancillary halogens. The photophysical properties of the complexes were found to vary by change of coordination geometry around the bismuth atom as well as the electronic density of the ligand. The detailed ground and excited state photophysical studies along with theoretical analysis provide the information that one type of complexes lead to strong absorption of visible light, hence favour applications in photovoltaics while a different molecular system leads to the phosphorescence emission. The combined comparative studies illustrate a design principle to develop novel bismuth coordination complexes as per the required applications. References 1. Yersin, H.; Rausch, A. F.; Czerwieniec, R.; Hofbeck, T.; Fischer, T. Coord. Chem. Rev. 2011, 255, 2622–2652. 2. Travis, W.; Knapp, C. E.; Savory, C. N.; Ganose, A. M.; Kafourou, P.; Song, X.; Sharif, Z.; Cockcroft, J. K.; Scanlon, D. O.; Bronstein, H.; Palgrave, R. G. Inorg. Chem. 2016, 55, 3393-3400
P37
© The Author(s), 2022
Made with FlippingBook Learn more on our blog