4-Butylpyridine is a heterocyclic organic chemical compound, 4-Butylpyridine is utilized as a additive in dye-sensitized solar cells (DSSCs). 4-Butylpyridine is a constituent of hole transport materials in perovskite and polymer solar cells, where its primary function is to improve photovoltaic efficiency by effectively reducing undesirable charge recombination processes, 4-Butylpyridine is also identified as a naturally occurring substance in plants such as Mentha arvensis.