Adsorption state of catalyst on photoanode is an important factor on influencing the performance of dye-sensitized photoelectrochemical cells (DS-PECs) for water splitting. Photoanode TiO2(1 + 2) was assembled with Ru(bpy)(3) phosphoric acid derivative (complex 1) as photosensitizer and complex 2 as water oxidation catalyst to compare with photoanode TiO2(1 + 3). The photocurrent density of photoanode TiO2(1 + 3) with catalyst 3 synthesized with only one end fixing on the surface of TiO2 is about four-fold of the photoanode assembled with catalyst 2 fixing with two claws on the surface of TiO2. The phenomenon should be caused by the littery arrangement and shorter distance of catalyst 2 from the active center of catalyst to TiO2 on the surface of semiconductor which led to lowly efficient electron transfer. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved
An alternative method for synthesis of biaryls has been developed through the Pd catalyzed desulfitative coupling reaction of sodium arylsulfinates with aryl bromides and chlorides. The procedure tolerates a variety of functional groups, such as cyano, formyl, acetyl, chloro, methoxy, trifluoromethyl and heteroaromatic unit. The desired products were obtained in moderate to excellent yields under relatively mild reaction conditions without additives, base or co-catalyst.
Chao Zhou Yarning Li Yang Lu Rong Zhang Kun Jin Xinmei Fu Chunying Duan
Dye-sensitized photoelectrochemical cell（DS-PEC） is an especially attractive method to generate hydrogen via visible light driven water splitting. Electrolyte, an essential component of DS-PEC, plays a great role in determining the photoactivities of devices for water splitting. When using phosphate buffer（pH = 6.4）as electrolyte, the DS-PEC displayed much higher photoactivity than using 0.1 M Na;SO;（pH = 6.4） as electrolyte. The insight is phosphate anion gathers together to form a negative electrostatic field on TiO;surface, which increases the resistance in the TiO;/catalyst and electrolyte interface and validly reduces the charge recombination from TiO;to the oxidized catalyst.
