A Bifunctional Saddle Shaped Small Molecule as Dopant Free Hole Transporting Mat

Herein, we synthesized a new bifunctional saddle-shaped organic small molecule named 2,2′,7,7′-tetrakis(N, N-di-p-methoxyphenyl-aniline)-α,β-cycloocta[1,2-b:4,3-b':5,6-b'':8,7-b''']tetrathiophenyl (α, β-COTh-Ph-OMeTAD). Comparing with spiro-OMeTAD, a star HTM for highly efficient perovskite solar ce