Enhancing organic photovoltaic performance with 3D-transport dual nonfullerene acceptors

We used dual nonfullerene acceptors Y6:FINIC with 3D charge transport features and polymer donor PM6 to fabricate sequential-process heterojunction (SHJ) and bulk heterojunction (BHJ) organic solar cells (OSCs). FINIC has...

Revealing Temperature-Dependent Polymer Aggregation in Solution with Small-Angle X-ray Scattering

Improving the morphology of bulk heterojunction active layers remains a primary challenge for organic photovoltaics (OPVs), and much research has been devoted to achieving this through modifying OPV casting solutions...

Combined nanoarchitectonics with self-assembly and electrosynthesis for flexible PTCDIs@PEDOT films with interpenetrating P-N heterojunction

A novel synthesis method for fabricating large area, uniform bulk-heterojunction film with electron donor and acceptor materials homogeneously distributed each other forming a bicontinuous network morphology is reported. The acceptor...

Quantifying the optimal thickness in polymer:fullerene solar cells from the analysis of charge transport dynamics and photoabsorption

We provide a semi-empirical equation that quantifies the optimal layer thickness in bulk heterojunction organic solar cells, which is based on time-of-flight and time-resolved microwave conductivity measurements and photoabsorption of a film.

Flexible, Rapid Response, Hybrid Inorganic-Organic SnSe2-PEDOT:PSS Bulk Heterojunction based High-Performance Broadband Photodetector

Photodetectors based on inorganic semiconductors demonstrate superior responsivity but their high thermal budget fabrication process is a serious impediment for emerging applications. Hybrid photodetectors based on organic-inorganic heterojunctions synergistically offer...

A Review on the Effects of ZnO Nanowire Morphology on the Performance of Interpenetrating Bulk Heterojunction Quantum Dot Solar Cells

Interpenetrating bulk heterojunction (IBHJ) quantum dot solar cells (QDSCs) offer a direct pathway for electrical contacts to overcome the trade-off between light absorption and carrier extraction. However, their complex three-dimensional structure creates higher requirements for the optimization of their design due to their more difficult interface defect states control, more complex light capture mechanism, and more advanced QD deposition technology. ZnO nanowire (NW) has been widely used as the electron transport layer (ETL) for this structure. Hence, the optimization of the ZnO NW morphology (such as density, length, and surface defects) is the key to improving the photoelectric performance of these SCs. In this study, the morphology control principles of ZnO NW for different synthetic methods are discussed. Furthermore, the effects of the density and length of the NW on the collection of photocarriers and their light capture effects are investigated. It is indicated that the NW spacing determines the transverse collection of electrons, while the length of the NW and the thickness of the SC often affect the longitudinal collection of holes. Finally, the optimization strategies for the geometrical morphology of and defect passivation in ZnO NWs are proposed to improve the efficiency of IBHJ QDSCs.

Nanometer-Scaled Landscape of Polymer:Fullerene Blends Mapped with Visible s-SNOM

Bulk heterojunction is one key concept leading to breakthrough in organic photovoltaics. The active layer is expectantly formed of distinct morphologies that carry out their respective roles in photovoltaic performance. The morphology-performance relationship however remains stymied, because unequivocal morphology at the nanoscale is not available. We used scattering-type scanning near-field optical microscopy operating with a visible light source (visible s-SNOM) to disclose the nanomorphology of P3HT:PCBM and pBCN:PCBM blends. Donor and acceptor domain as well as intermixed phase were identified and their intertwined distributions were mapped. We proposed energy landscapes of the BHJ active layer to shed light on the roles played by these morphologies in charge separation, transport and recombination. This study shows that visible s-SNOM is capable of profiling the morphological backdrop pertaining to the operation of high performance organic solar cells.