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 universal method is reported to form graded bulk heterojunction (BHJ) organic photovoltaic devices (OPVs) by a simple solvent-fluxing process. Donors are enriched at the anode and acceptors are enriched at cathode side, matching the gradient electron and hole current across the film. Efficiency enhancements by 15-50% are achieved for all BHJ systems tested compared with the optimized regular ...

Fermi-level pinning behavior has been observed at the free surface, oxide interface, metal interface, MBE grown surface, stop-regrown homojunction, and misfit-dislocation pinned heterojunction of GaAs. Theories of such behavior are numerous and disparate. Theories of ideal heterojunction band offsets are less diverse, but have still not converged to a single mechanism. Recent studies of heteroj...

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 ...

Small molecule BODIPY dyes incorporating conjugated substituents at the β sites have been synthesized. Solution processed inverted bulk heterojunction cells were fabricated from the blends of the dyes and PC(71)BM. The cells exhibited very high open-circuit voltages (>0.9 V) and a high conversion efficiency of 3.22% has been achieved.

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%.

Traditional low-molecular weight colorants that are widely applied in textile coloration, for printing purposes and nonlinear optics, now afford bulk heterojunction solar cells in combination with soluble C(60) fullerene derivative PCBM with power conversion efficiencies up to 1.7% under standard solar radiation.

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...