An investigation was performed on the suitability of carbon materials, metallic lead and its alloys as substrates for zinc negative electrode in acid PbO2-Zn single flow batteries. The zinc deposition process was carr...An investigation was performed on the suitability of carbon materials, metallic lead and its alloys as substrates for zinc negative electrode in acid PbO2-Zn single flow batteries. The zinc deposition process was carried out in the mediumofl mol.L 1H2SO4 at room temperature. No maximum current appears on the potentiostatic current transients for the zinc deposition on lead and its alloys. With increasing overpotential, the progressive nucleation turns to be a 3D-instantaneous nucleation process for the resin-graphite composite. Hydrogen evolution on the graphite composite is effectively suppressed with the doping of a polymer resin. The hydrogen evolution reaction on the lead is relatively weak, while on the lead alloys, it becomes serious to a certain degree. Although the ex- change current density of zinc deposition and dissolution process on the graphite composite is relatively low, the zinc corrosion is weakened to a great extent. With the increase of deposition time, zinc deposits are more compact. The cyclings of zinc galvanostatic charge-discharge on the graphite composite provide more than 90% of coulombic and 80% of energy efficiencies, and exhibit superior cycling stability during the first 10 cycles.展开更多
The nanocomposites of ZnO-SnO_2 and In_2O_3-SnO_2 were prepared by wet chemical co-precipitation method as a novel semiconductor gas sensing materials for the detection of environmentally toxic gases.Controlled prepar...The nanocomposites of ZnO-SnO_2 and In_2O_3-SnO_2 were prepared by wet chemical co-precipitation method as a novel semiconductor gas sensing materials for the detection of environmentally toxic gases.Controlled preparation parameters were critical towards the grain size and crystallinity of the obtained nanocomposites.The results showed that these nanocomposites exhibited high sensitivity and selectivity for the detection of CO and NO_x,and the sensitivity depended on the composition of the composite,calcination temperature and operating temperature.The gas sensing properties of the sensors were further improved through incorporation of dopants and surface additives.The gas sensing mechanism was also discussed by X-ray photoelectron spectroscopic (XPS) and temperature-programmed desorption (TPD) studies.展开更多
基金Supported by the National Basic Research Program(973 Program)of China(2010CB227201)the State Key Program of National Natural Science of China(21236003)+2 种基金the National Natural Science Foundation of China(21476022)the Fundamental Research Funds for the Central Universities(JD1515 and YS1406)Beijing Higher Education Young Elite Teacher Project(YETP0509)
文摘An investigation was performed on the suitability of carbon materials, metallic lead and its alloys as substrates for zinc negative electrode in acid PbO2-Zn single flow batteries. The zinc deposition process was carried out in the mediumofl mol.L 1H2SO4 at room temperature. No maximum current appears on the potentiostatic current transients for the zinc deposition on lead and its alloys. With increasing overpotential, the progressive nucleation turns to be a 3D-instantaneous nucleation process for the resin-graphite composite. Hydrogen evolution on the graphite composite is effectively suppressed with the doping of a polymer resin. The hydrogen evolution reaction on the lead is relatively weak, while on the lead alloys, it becomes serious to a certain degree. Although the ex- change current density of zinc deposition and dissolution process on the graphite composite is relatively low, the zinc corrosion is weakened to a great extent. With the increase of deposition time, zinc deposits are more compact. The cyclings of zinc galvanostatic charge-discharge on the graphite composite provide more than 90% of coulombic and 80% of energy efficiencies, and exhibit superior cycling stability during the first 10 cycles.
基金This research was supported by the National Natural Science Foundation of China （No. 20577001）；Beijing Natural Science Foundation （No. 8042016 and 8062011）.
文摘The nanocomposites of ZnO-SnO_2 and In_2O_3-SnO_2 were prepared by wet chemical co-precipitation method as a novel semiconductor gas sensing materials for the detection of environmentally toxic gases.Controlled preparation parameters were critical towards the grain size and crystallinity of the obtained nanocomposites.The results showed that these nanocomposites exhibited high sensitivity and selectivity for the detection of CO and NO_x,and the sensitivity depended on the composition of the composite,calcination temperature and operating temperature.The gas sensing properties of the sensors were further improved through incorporation of dopants and surface additives.The gas sensing mechanism was also discussed by X-ray photoelectron spectroscopic (XPS) and temperature-programmed desorption (TPD) studies.
