A Nonfullerene Small Molecule Acceptor with 3D Interlocking Geometry Enabling Efficient Organic Solar Cells

Abstract

A new 3D nonfullerene small-molecule acceptor is reported. The 3D interlocking geometry of the small-molecule acceptor enables uniform molecular conformation and strong intermolecular connectivity, facilitating favorable nanoscale phase separation and electron charge transfer. By employing both a novel polymer donor and a nonfullerene small-molecule acceptor in the solution-processed organic solar cells, a high-power conversion efficiency of close to 6% is demonstrated.

Reduced voltage losses yield 10% efficient fullerene free organic solar cells with >1 V open circuit voltages

“…The moderate PL quenching of PffBT4T-2DT:FBR film indicate a coarse nano-morphology which is strongly related to the crystalline nature of PffBT4T-2DT previously reported and discussed above. 38 …”

A twisted monomeric perylenediimide electron acceptor for efficient organic solar cells

“…Moreover, some PDI derivatives intend to form excimers that perform as traps for excitation energy which severely hinder the efficiency of exciton splitting and the further performance of the OSCs [30][31][32][33]. Considerable effort has been dedicated to design and synthesize PDI-based acceptors with twisted structures in order to weaken aggregation and restrict crystalline of molecules [34][35][36][37][38][39]. PDI monomers are alternative non-fullerene acceptors.…”

Achieving high performance non-fullerene organic solar cells through tuning the numbers of electron deficient building blocks of molecular acceptors

“…The charge transport ability, photoluminescence, morphology, and crystallinity of the blend films were investigated and consistent with the photovoltaic performances. During preparation of this manuscript, SF-PDI4 with different alkyl chains (dihexyl and 2-ethylhexyl) was reported independently as nonfullerene acceptor for OSCs by two groups [30,35]. Both of them afforded high efficiencies with 5.3% and 5.98%.…”