Hong-Chun Yuan

Morphology, photophysics and optoelectronics of P3HT nanoparticles and TiO2 nanorods composite

Morphology and photophysics of polymers are critical to the performance of organic optoelectronics. In this work, poly(3-thiophene) (P3HT) nanoparticles were successfully fabricated by the miniemulsion and reprecipitation methods. The P3HT nanoparticles demonstrated uniform distribution with the domain size of ∼40 nm. The photophysics of P3HT nanoparticles was investigated by absorption and steady-state and time-resolved PL spectroscopy. P3HT nanoparticles showed more ordered and longer conjugation length than pristine P3HT. At the same time, P3HT nanoparticles showed aggregate species which are favorable for interchain charge transfer. The organic/inorganic hybrid photodetectors based on P3HT and TiO2 nanorods were fabricated. The superior performance of the photodetector based on P3HT nanoparticle and TiO2 nanorods comes from the efficient charge transfer and large donor/acceptor interface.

Photoelectrocatalytic degradation of Rhodamine B using graphene and titanium dioxide composite catalyst

Graphene and titanium dioxide (TiO2) composite catalyst has been synthesized by hydrothermal synthesis method, and used for the degradation of Rhodamine B (Rh.B) in water. The photoelectrocatalytic activity of this composite was evaluated by decomposing of Rh.B in water under visible or UV light irradiation. The degradation results indicated that the photoelectrocatalytic performance of this composite catalyst was greatly enhanced due to the improved adsorption performance and separation efficiency of photo-generated carriers possibly. The composite with graphene content of 10 wt.% exhibited superior activity under UV light irradiation. After 30 min of reaction, the photoelectrocatalytic degradation ratio of Rh.B was about 96% when pH = 6–7. The results of this work provide a good method for the treatment of organic wastewater with high performance.

Anode-supported BaZr0.8Y0.2O3−δ membranes by tape casting and suspension spraying

Dense BaZr0.8Y0.2O3−δ (BZY) proton-conducting electrolyte membranes are successfully fabricated on NiO–BaZr0.1Ce0.7Y0.2O3−δ(NiO–BZCY) using tape casting combined with suspension spraying technique. The NiO–BZCY anode substrates were prepared by the tape-casting method and the BZY electrolyte membranes were prepared on the NiO-BZCY anodes by suspension spraying. The thermal decomposition of the anode green tape prepared by tape casting was investigated by thermogravimetry-differential thermal analysis while the phase structure and the morphology of the anode/electrolyte bi-layers were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). No obvious reaction was found between NiO and BZCY in anode substrates and gas-tight BZY membranes were achieved after co-sintering at 1450∘C. With Sm0.5Sr0.5CoO3−δ–Ce0.8Sm0.2O2−δ(SSC–SDC) as the composite cathode, a maximum power density of 121 mW cm−2 was obtained at 650∘C for the single cell with 23 μm thick BZY electrolyte. Resistances of the tested cell were investigated under open circuit conditions at different operating temperatures by impedance spectroscopy.

Higher-order nonclassical effects generated by multiple-photon annihilation-then-creation and creation-then-annihilation coherent states*

We explore two observable nonclassical properties of quantum states generated by repeatedly operating annihilation-then-creation (AC) and creation-then-annihilation (CA) on the coherent state, respectively, such as higher-order sub-Poissonian statistics and higher-order squeezing-enhanced effect. The corresponding analytical expressions are derived in detail depending on m. By numerically comparing those quantum properties, it is found that these states above have very different nonclassical properties and nonclassicality is exhibited more strongly after AC operation than after CA operation.