High performance asymmetrical push-pull small molecules end-capped with cyanophenyl for solution-processed solar cells.

Two novel asymmetrical push-pull small molecules have been synthesized successfully, consisting of triphenylamine and diketopyrrolopyrrole as a fundamental dipolar D-π-A structure with ethynylbenzene as the π-bridge. TPATDPPCN end-capped with cyanophenyl exhibits a low optical band gap of 1.65 eV, and an impressive PCE of 5.94% has been achieved.

D-π-A-π-D type benzothiadiazole-triphenylamine based small molecules containing cyano on the π-bridge for solution-processed organic solar cells with high open-circuit voltage.

Two novel D-π-A-π-D structured small molecules composed of benzothiadiazole and triphenylamine were designed and synthesized. with cyano on the π-bridge exhibited a deep HOMO energy level, resulting in an impressive V(OC) of up to 1.04 V with a PCE of 3.85%, while non-cyano substituted yielded a V(OC) of 0.94 V and a PCE of 1.99%.

Aromatic nitration in liquid Ag0.51K0.42Na0.07NO3.

Aromatic molecules have a strong affinity for silver(I) and dissolve to a limited extent in Ag 0.51K 0.42Na 0.07NO 3, a low-melting eutectic mixture of silver, potassium, and sodium nitrates. Aromatic nitration in this inorganic ionic liquid leads to products which arise from nonelectrophilic substitution pathways.

Sonochemical synthesis of mesoporous transition metal and rare earth oxides.

Straight-extended layered mesostructures based on transItion metal (Fe, Cr) and rare earth (Y, Ce, La, Sm, Er) oxides are synthesized by sonication for 3 h. After a longer period of sonication (6 h), hexagonal mesostructures based on Y- and Er-oxides are obtained. The surface areas of the Y-based hexagonal mesophases before and after extraction are 46.5, 256 m2/g, respectively. For Er-based hexagonal mesophases, the surface areas before and after extraction are 157 and 225 m2/g. The pore sizes after extraction are 5.0 and 2.2 nm for Y- and Er-based mesophases, respectively. Hexagonal mesostructures are also obtained for Zr-based material after sonication for 3 h and the hexagonal structure is still maintained after calcinations at 400 degrees C for 4 h, although the surface area is only 35 m2/g.

Sonochemical synthesis of cerium oxide nanoparticles-effect of additives and quantum size effect.

Cerium oxide (CeO(2)) nanoparticles were prepared sonochemically, by using cerium nitrate and azodicarbonamide as starting materials, and ethylenediamine or tetraalkylammonium hydroxide as additives. The additives have a strong effect on the particle size and particle size distribution. CeO(2) nanoparticles with small particle size and narrow particle size distribution are obtained with the addition of additives; while highly agglomerated CeO(2) nanoparticles are obtained in the absence of additives. Monodispersed CeO(2) nanoparticles with a mean particle size of ca. 3.3 nm are obtained when tetramethylammonium hydroxide (TMAOH) is used as the additive and the molar ratio of cerium nitrate/azodicarbonamine/TMAOH is 1/1/1. Blue shifts of the absorption peak and the absorption edges of the products are observed in the UV-Vis absorption spectra as a result of the quantum size effect. The samples have been characterized using powder XRD, TEM, DLS, and absorption spectra.