Methoxy management of side chains on the carbazole-diphenylamine derivatives based hole transport materials for perovskite solar cells: A theoretical design and experimental research

Molecular design is the important approach for realizing the improvement of performance for hole transport materials (HTMs) in perovskite solar cells (PSCs). In this work, starting from the carbazole-diphenylamine de-rivatives based HTMs, three molecules (CX1-CX3) are designed through methoxy management on the side chains. The calculated results indicated that CX1-CX3 yield different molecular arrangements through methoxy management on the side chains, resulting in adjusting the intermolecular coupling strength and hole transport capabilities. In comparison with the designed CX2 and CX3, CX1 exhibits a higher hole mobility, stronger interfacial interactions and more efficient charge transfer at perovskite/HTMs interface. Hence, under the same conditions, PSC devices based on CX1 yields a PCE of 22.13% higher than those of other molecules CX2 (20.96%) and CX3 (19.72%). These findings highlight the significance of methoxy management on the side chains in HTMs for the photovoltaic performance of PSCs, and reveal the potential of molecular engineering for the design of efficient HTMs.