Zhongling Zhao

Study of A- and B- Substituted Perovskite CDPF Catalyst and Its’ Catalytic Activity

A- and B- substituted perovskite catalyst for CPDF, La0.6K0.4CoO3 and LaCo0.8Fe0.2O3 were prepared by citric method. Morphology, components and structure of catalyst were characterized by Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS) and X-ray diffraction (XRD). The catalytic activity of catalyst on soot combustion was determined by Thermogravimetry (TG). Results show that the catalyst had good catalytic performance. The ignition temperature of model soot was 342 °C when mixed with A- substituted perovskite catalyst La0.6K0.4CoO3 and 377 °C with B- substituted perovskite catalyst LaCo0.8Fe0.2O3, while 595 °C of model soot without catalyst. The catalytic activity can be attributed to the catalyst endowed model soot with lower combustion activation energy. Therefore, these substituted perovskites may be good candidates of noble metal for CPDF.

Pore-forming Technology Development of Polymer Separators for Power Lithium-ion Battery

To investigate the impact of the pore-forming agent on the performance of polymer membranes, four Al2O3/PVDF-HFP separators with different pore-forming agents, n-butanol, deionized water, ethanol, and isopropanol are prepared by adding Al2O3 as the filler. The wettability, morphology, mechanism strength, and electrochemical properties of above membranes are characterized. Results show that the membrane prepared with n-butanol as the pore-forming agent has the best property, with electrolyte uptake rate of 420 %, ion transference number of 0.90, tensile strength of 14.93 MPa, conductivity of 0.50 ms/cm−1, electrochemical stability of 5.2 V, and discharging specific capacity of 108 mAh/g at 4C with a LiFePO4 half-cell.

Studies on the Working Mode of Hyperbranched New Materials STOBA in Lithium-ion Battery Cathode Materials

Self-terminated oligomers with hyperbranched architecture, also known as STOBA, are combined with lithium-ion battery cathode materials by two different ways: mechanical blending and surface coating. The comparative electrochemical analyses of the assembled coin cells demonstrate that for the materials gained through mechanical blending, no blocking effects are observed at high-temperature condition. For the surface coating ones, STOBA has slight impact on the cell performance at room temperature, but when the ambient temperature exceeds the cross-linking temperature, large area of cross-linking will occur on the surface of the electrode materials, which prevents the lithium ion from extracting and inserting. As a result, the battery totally loses charge–discharge capacity in the high rate discharge condition to ensure the safety when operating at high temperatures.

Preparation and Property of High Heat-Resistant Ceramic Composited PET Separator

Polyethylene terephthalate (PET)–Al2O3 ceramic composited separator is prepared with organic adhesives PDA, inorganic adhesives, silane-coupling agent, and colloidal silica. The obtained separator is characterized in different ways. Morphology characterization by SEM shows that porous separator is obtained, and Al2O3 is evenly distributed on it. The Gurley number of the separator is 8 s/100 cc. Thermal behavior investigation and linear sweep voltammetry test show that the prepared separator has an outstanding thermal performance and electrochemical stability. Half-cell assembled with the composited separator reveals an outstanding cycle performance and a good rate performance. Therefore, the separator may be a suitable and excellent candidate for application in power battery, especially the one with higher safety.

Synthesis and Nox Gas Sensing Properties of In1.82 ni0.18o3 Electrospun Nanofibers

The detection and control of nitrogen oxides (NOX) in exhaust gases emitted by combustion engines has been an important subject in the last decades. Regulations of vehicle emissions focus on the minimization of NOX in automotive exhaust gases, particularly in lean combustion exhaust gases. Fast response times and high sensitivity of NOX sensor in lean combustion environments are necessary to meet those regulations. In this paper a new sensing material (In1.82Ni0.18O3 nanofibers) was synthesized via a simple and effective electrospinning method. The morphology and crystal structure of the as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectra (XPS). Potentiometric-type NOX sensor based on yttria-stabilized zirconia (YSZ) with In1.82Ni0.18O3 nanofibers sensing electrode was prepared and its gas sensing properties were also tested. The results show that large-scale In1.82Ni0.18O3 nanofibers with diameters ranging from 40 to 80 nm and lengths of several tens of micrometers were successfully synthesized by this technique. A loose reticular porous non-woven lap structure was formed by many fibers. The results of sensing tests show that the sensitivity ∆EMF of sensor prepared can reach 85 mV for 500 ppm NO, and the ∆EMF is stable. Moreover, the sensor also exhibited fast response time and good selectivity.