Zhexun Yu

Quasi-solid-state dye-sensitized solar cell fabricated with poly (β-hydroxyethyl methacrylate) based organogel electrolyte

A novel freestanding poly (β-hydroxyethyl methacrylate), PHEMA-based organogel electrolyte is developed simply by optimization of the solution polymerization in the same solvent as the organic electrolyte for dye-sensitized solar cells (DSCs). The room temperature ionic conductivity of the gel electrolyte is 4.54 × 10−3 S cm−1, and the conduction behavior can be well described by the free volume model. The quasi-solid-state dye-sensitized solar cell fabricated with this PHEMA-based polymer gel electrolyte can present high energy conversion efficiency up to 7.5%. Preliminary long-term stability test further reveals that this quasi-solid-state electrolyte exhibits good stability after 1000 h thermal test in comparison with the DSCs based on corresponding liquid electrolyte.

Room temperature fabrication of porous ZnO photoelectrodes for flexible dye-sensitized solar cells

We fabricated ZnO photoelectrodes at room temperature by doctor-blading ZnO gel; the adequate interparticle connection and the effective ammonia activation process improved the flexible DSCs efficiency to 3.8% (under 100 mW cm(-2)).

Low Cost, Environmentally Friendly, In Situ Prepared Quasi-Solid-State AlI3 Electrolyte for Dye-Sensitized Solar Cells

The magnetic properties of magnetosome magnetite are of interdisciplinary interest because magnetosomes are potential carriers of natural remanent magnetization and paleoenvironment, as well as novel nano-biomaterials in biotechnological and biomedical applications. We carried out magnetic and electron transmission microscopy analyses of fresh Magnetospirillum magneticum AMB-1 whole cells and isolated magnetosomes. Results revealed that AMB-1 synthesized single-domain magnetite magnetosomes, which are arranged in the form of linear fragmental chain. The distinct differences of magnetic properties between these two samples can be faithfully interpreted in terms of spatial arrangement of magnetosomes and magnetostatic interaction. For the whole cells, the strong intra-chain interactions and weak inter-chain interactions generate behaviors of non-interacting uniaxial single-domain particles. Its delta-ratio is 3.0 and passes the Moskowitz test. In contrast, the isolated magnetosome sample has reduced values of coercivity and delta-ratio (1.5), due to increasing three-dimensional magnetostatic interactions and collapse of magnetosome chains. These observations provide useful insights into applications of the biogenic magnetite (magnetosomes) in magnetic nano-materials and magnetofossils in the paleomagnetic and environmental magnetism.