Abstract:
Abstract. This study explores the influence of solvent environments on the spectroscopic and photochemical properties of ruthenium(II) polypyridyl complexes, with a focus on their application in sustainable hydrogen production and solar energy conversion. These complexes show great potential as photocatalysts for clean energy technologies; however, their efficiency and stability are highly dependent on the surrounding chemical environment. Using high performance liquid chromatography (HPLC) and UV-Vis spectroscopy, the research evaluates electronic transitions and photochemical behavior under continuous irradiation. Notably, the complex [(tbbpy)2Ru(tpphz) (Pt2)2] exhibited a significant metal-to- ligand charge transfer (MLCT) shift from 486 nm to 441 nm over 24 hours in polar solvents such as acetonitrile and methanol indicating solvent-induced ligand exchange and enhanced charge transfer. The inclusion of PtI, substantially improved photocatalytic performance, achieving a turnover number (TON) of 276. Measurement precision was confirmed by low standard deviations (±1.1 to ±1.5 nm) and relative standard deviation (RSD) values below 3%. These findings highlight the critical role of solvent polarity and ligand design in optimizing photocatalyst efficiency and stability for sustainable energy applications. While polar solvents enhance charge-transfer processes, they may compromise long-term stability. The study recommends the development of more robust ligands and the exploration of environmentally friendly solvents to advance photocatalytic technologies in line with environmental sustainability goals.
