Novel star shaped D-π-D-π-D and (D-π)2-D-(π-D)2, anthracene-based hole transporting material for perovskite solar cells
Two types of novel star shaped molecular architectures D-π-D-π-D and (D-)2-D-(-D)2 anthracene (ANTTPA, AOME, AOHE) based hole transporting materials are designed for hybrid perovskite solar cells through Gaussian 09 computation program using B3LYP/6-31g (d, p) basis set level. The HOMO energy level of designed materials has aloft HOMO energy level compared to perovskite HOMO energy level, which is more facile for hole transport from hole transporting layer to oxidized perovskite layer. Hereafter, anthracene-based derivatives were synthesized from Buchwald-Hartwig and Mizoroki-Heck cross coupling reactions. The behaviors of transporting of charges were determined by both UV- visible absorbance and the emission spectroscopy through solvatochromism experiments. Further, the electrochemical properties also prove that the synthesized compounds having optimal HOMO energy level in the TiO2/perovskite/HTM interface. Our HTMs has good film formation compared to the spiro-OMeTAD, which is confirmed by SEM images. At this end, the obtained theoretical and experimental data attributes that the suitability of designing anthracene-based derivatives have the potential to be used as hole transporting materials in organic-inorganic hybrid perovskite solar cells.