Vertical arrays of ZnO nanowires can decouple light absorption from carrier collection in PbS quantum dot solar cells and increase power conversion efficiencies by 35%. The resulting ordered bulk heterojunction devices achieve short-circuit current densities in excess of 20 mA cm(-2) and efficiencies of up to 4.9%.

The importance of symmetry breaking was investigated in bulk heterojunction solar cells with a conventional device structure. Artificial symmetry breaking was built up by introducing a titanium suboxide. With sufficient symmetry breaking, the influence of the cathode work-function can be diminished, thereby extracting the same level of open circuit voltage regardless of metal work-function.

A series of unsymmetrical π-conjugated small molecules have been constructed from meso-alkyl substituted porphyrins as the central unit and 3-ethylrhodanine as the terminal group. Using PC71BM as an acceptor, and these small molecules as electron donors in solution-processed bulk-heterojunction solar cells, a high power conversion efficiency of 6.49% has been achieved.

Side chain engineering of an n-type polymer provides a means of maintaining solubility while increasing crystallinity and electron mobility, leading to enhanced photocurrent. Bulk heterojunction solar cells composed of a side chain engineered copolymer (PNDIS-30BO) as acceptor and PSEHTT as donor give 10.4 mA cm(-2) photocurrent and 4.4% efficiency.

A single isomer of fullerene bisadduct, PC61PF, was obtained from commercially available fullerene derivative, PC61BM, in one pot over two steps. The tether-directed remote functionalization approach provided a very simple and fast method to produce a single isomer of fullerene bisadduct with good yield and easy purification. Bulk heterojunction organic solar cells containing the bisadduct was ...

We report the synthesis of a solution-processable, dodecyloxyphenyl-substituted azafullerene monoadduct (DPC59N) and its application as electron acceptor in bulk heterojunction organic solar cells (BHJ-OSCs). Due to its relatively strong absorption of visible light, DPC59N outperforms PC60BM in respect to short circuit current (JSC) and external quantum efficiency (EQE) in blends with donor P3HT.

Annulated thiophene perylene bisimides and their triphenyl-amine based oligomers have been synthesized. One of the oligomers FPTTPA has been demonstrated to be an efficient electron donor in bulk heterojunction (BHJ) organic solar cells, giving a power conversion efficiency of 1.42%.

Zaifei Ma, Wenjun Sun, Scott Himmelberger, Koen Vandewal, Zheng Tang, Jonas Bergqvist, Alberto Salleo, Jens Wenzel Andreasen, Olle Inganäs, Mats R Andersson, Christian Müller, Fengling Zhang and Ergang Wang, Structure-Property Relationships of OligothiopheneIsoindigo Polymers for Efficient Bulk-Heterojunction Solar Cells, 2014, energy and environmental science, (17), 1, 361-369. http://dx.doi.o...

A series of acceptor-donor-acceptor molecules containing terminal BODIPY moieties conjugated through the meso position were synthesized. Deep LUMO energy levels and good visible absorption led to their use as acceptors in bulk heterojunction solar cells. Inverted devices were fabricated, reaching efficiencies as high as 1.51%.