Solid state self-assembly of triptycene-based catechol derivatives by multiple O-H…O hydrogen bonds

Single crystals of two triptycene-based catechol derivatives 1 and 2 were obtained,and their X-ray crystal structural studies showed that the two tecton molecules had different conformations in the solid state,and they could self-assemble into interesting 3D networks with solvent molecules included inside, in which multiple O-H…O hydrogen bonds played important roles.

Bioinspired molecules design for bilateral synergistic passivation in buried interfaces of planar perovskite solar cells

Trap-mediated energy loss in the buried interface with non-exposed feature constitutes one of the serious challenges for achieving high-performance perovskite solar cells(PSCs).Inspired by the adhesion mechanism of mussels,herein,three catechol derivatives with functional Lewis base groups,namely 3,4-Dihydroxyphenylalanine(DOPA),3,4-Dihydroxyphenethylamine(DA)and 3-(3,4-Dihydroxyphenyl)propionic acid(DPPA),were strategically designed.These molecules as interfacial linkers are incorporated into the buried interface between perovskite and SnO_(2) surface,achieving bilateral synergetic passivation effect.The crosslinking can produce secondary bonding with the undercoordinated Pb^(2+) and Sn^(4+) defects.The PSCs treated with DOPA exhibited the best performance and operational stability.Upon the DOPA passivation,a stabilized power conversion efficiency(PCE)of 21.5%was demonstrated for the planar PSCs.After 55 days of room-temperature storage,the unencapsulated devices with the DOPA crosslinker could still maintain 85%of their initial performance in air under relative humidity of-15%.This work opens up a new strategy for passivating the buried interfaces of perovskite photovoltaics and also provides important insights into designing defect passivation agents for other perovskite optoelectronic devices,such as light-emitting diodes,photodetectors,and lasers.