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An acceptor-donor-acceptor (A-D-A) three-dimensional (3D) small molecule acceptor (SFTTIC), using spirobifluorene as the core unit linking with four thieno[3,2-b]thiophenes (TT) and end-capped with 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (INCN) was developed for solution processed organic solar cells. SFTTIC has a high absorption coefficient up to 3.12 × 105 mol-1 cm-1, good thermal stability and appropriate energy levels. The optimized power conversion efficiency (PCE) of 5.66% and 4.65% were achieved for the devices with PBDB-T:SFTTIC and PTB7-Th:SFTTIC, respectively.

Mesoporous silica materials with pore diameters of 2–5 nm have been prepared using ascorbic add as a nonsurfactant template or pore-forming agent in HCl-catalyzed sol-gel reactions of tetraethylorthosilicate, followed by removing the ascorbic acid compound by extraction with ethanol. Characterization results from nitrogen sorption isotherm, powder X-ray diffraction and transmission electron microscopy indicate that me materials have large specific surface areas (e.g. 1000 m2/g) and pore volumes (e.g. 0.8 cm3/g). The mesoporosity is arisen from interconnecting disordered wormlike channels and pores with relatively broad size distributions. As the ascorbic acid concentration is increased, the pore diameters and pore volumes of the materials increase.

Monolithic and transparent Ti-incorporated mesoporous silica materials of large size (e.g. 2 mm) in dimension have been prepared with tartaric add (TA) as template via sol-gel reactions of tetraethyl orthosilicate (TEOS) and tetrabutyl titanate (TBT). The materials are characterized by infrared (IR), nitrogen adsorption-desorption isotherms, powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results indicate that the monolithic materials exhibit large specific surface areas (ca. 1200 mVg) and pore volumes (ca. 0.900 cm3/g).