Jinan Niu

Facile synthesis, structure and enhanced photocatalytic activity of novel BiOBr/Bi(C2O4)OH composite photocatalysts

Novel composite photocatalysts BiOBr/Bi(C2O4)OH were successfully fabricated via a chemical etching method. After flower-like Bi(C2O4)OH microstructure assembled by nanorods was etched by KBr under an appropriate acidic condition, BiOBr nano-rods could be in-situ generated in nanorods, forming a heterostructure. The heterostructures exhibited a commendable photocatalytic performance toward the degradation of rhodamine B under the visible light irradiation. The effective separation and transfer of the photogenerated electrons and holes were believed to be the main factor for the enhanced activity, which resulted from the intrinsic characteristic of p-n junction. The responsible mechanism was detailedly discussed, and the photogenerated holes and O2- radicals were confirmed to be the main active species for the photodegradation of RhB.

Synthesis and hydrogenation of anatase TiO2 microspheres composed of porous single crystals for significantly improved photocatalytic activity

Anatase microspheres composed of porous single crystals were successfully synthesized via a facile route without preseeding treatment and then further modified using a surface hydrogenation process. The porous materials obtained exhibit excellent photocatalytic activity and good recyclability leading to great potential in practical applications.

Effect of composition of starting materials of Mo–Si on self-propagating high temperature SHS reaction

Abstract An experimental study of the self-propagating high temperature synthesis of Mo–Si alloys was conducted from elemental powder compacts. Test specimens with seven compositions, including Mo/Si = 1∶1·25, 1∶1·50, 1∶1·75, 1∶2·00, 1∶2·25, 1∶2·50 and 1∶2·75 respectively, were employed. Experimental evidence showed that a combustion wave featuring a spinning reaction zone can be observed. When the powder compacts are from Mo∶1·25Si to Mo∶1·75Si, the combustion temperature and the propagation velocity of combustion wave increase with increasing silicon in the sample, and the combustion products are composed of MoSi2, Mo5Si3 and Mo. However, when the powder compacts are from Mo∶2·25Si to Mo∶2·75Si, the combustion temperature and the propagation velocity decrease rapidly as the silicon in the compact increases, and the combustion products are composed of MoSi2 and Si. The sample with Mo/Si = 1∶2·00 possesses the highest combustion temperature (1628·9 K) and propagation velocity (3·13 mm s−1). A single-phase MoSi2 is synthesised by the Mo/Si = 1∶2·00 sample.