Halogenated carbazole-based SAMs containing different halogen atoms and varying length of aliphatic chain were synthesized in this work. All materials have been tested in organic photovoltaics by prof. T. Anthopoulos research group (KAUST). This investigation demonstrated the influence of halogen substitutions on the energetics of synthesized molecules and overall performance, including stability under continuous illumination, setting Cl-2PACz to be the leader among tested materials, which yielded in the 18.5 % PCE (18.9 % with n-dopant benzyl viologen).