In the present work, novel blend polymer electrolyte membranes using poly(vinyl alcohol) (PVA), doped with hypophosphorous acid (H3PO2) and reinforced with porous niobium oxide (Nb2O5) microparticles in different comp...In the present work, novel blend polymer electrolyte membranes using poly(vinyl alcohol) (PVA), doped with hypophosphorous acid (H3PO2) and reinforced with porous niobium oxide (Nb2O5) microparticles in different compositions were prepared by the solution-casting technique. Their phase behavior and ionic conductivity were studied by differential scanning calorimetric (DSC), thermogravimetric analysis (TGA) and impedance spectroscopy (IS) in the radio-frequency range. Using a constant H3PO2/PVA weigh ratio of 0.25, it was found that the water content in the blended hydrogel membranes increased with increasing the filler Nb2O5 content, thus increasing the electrical conductivity. However, the suitable weight ratio of Nb2O5:(H3PO2/PVA) for the blend performance (both mechanically and electrically) was x = 0.075, with a maximum ionic conductivity of 2.7?× 10﹣3 S·cm﹣1 at 120°C. For all blends prepared, the lost tangent plots show asymmetrical peaks, as a consequence of correlations in the mobile ion diffusion as a function of frequency. Although this “universal dynamic response” was observed at all temperatures, variations in the tan(δ) relaxation peaks indicate a decrease of ionic correlation when the temperature is increased. Both the dc conductivity and tan(δ) peaks frequency dependency are thermally activated, following an Arrhenius-type behavior with activation energy of the same order, indicating that the corresponding ionic processes have the same origin, i.e., proton jump among available sites in the polymer matrix. The additions of oxide particles to the membranes improve their thermal and electrical properties, attributed to an approximation effect.展开更多
The nanocomposite electrolytes composed of Smo.2Ce0.801.9 （SDC） nanorods enclosed by { 110} and { 100} facets and a binary carbonate （（Lio.52Nao.48）2CO3, LNC） were prepared by a wet mixing method to investigate ...The nanocomposite electrolytes composed of Smo.2Ce0.801.9 （SDC） nanorods enclosed by { 110} and { 100} facets and a binary carbonate （（Lio.52Nao.48）2CO3, LNC） were prepared by a wet mixing method to investigate the conduction mechanism. The X-ray diffraction （XRD）, scanning electron microscopy （FESEM） and transmission electron microscopy （TEM） techniques were em- ployed to characterize the phase components and microstructures of SDC nanorods and SDC nanorods/LNC composite electrolytes. X-ray powder diffraction showed that a well-cubic fluorite structure was formed. The AC impedance spectroscopy and DC polariza- tion method were used to measure the electrical conductivities of nanocomposite electrolytes under different conditions. The overall ionic conductivities of nanocomposite electrolytes in the air and hydrogen atmospheres were measured up to 82 and 96 mS/cm at 650 ℃, respectively. Additionally, the protonic and oxide ionic conductivities of nanocomposite electrolytes were found to reach 20 and 18 mS/cm at 650 ℃, respectively. The conduction mechanism was discussed in detail by comparing the conductivities of nanocom- posite electrolytes. The protonic conductivity of SDC nanorods/LNC nanocomposite was higher than oxide ionic conductivity. The melt of LNC and the interface layer may make a dominant contribution to oxide ions and protonic conductivity in air and hydrogen atmosphere, respectively.展开更多
The conductivity of the solid electrolyte based on urea and thiourea has reached 6. 84 × 10-3 S. cm-1 at room temperature. Analysing the conductive process of this electrolyte we found that thiourea changes into ...The conductivity of the solid electrolyte based on urea and thiourea has reached 6. 84 × 10-3 S. cm-1 at room temperature. Analysing the conductive process of this electrolyte we found that thiourea changes into ammonium thiocyanate at a high temperature, which ionizes into ions, and can conduct the current. We obtained a red color substance through electrolysing the SPE. Analysing it with IR, UV and FAB, we confirmed that it is a polymer with a structure (SCN)n. It is proved that the aninon is SCN-. When weadded HCl into the acetone solution of the SPE, it was found that white precipitation material appeared in the solution, which was identified as NH4Cl, so the canon is NH4+.展开更多
Due to the high specific capacity, low cost, and environmental friendliness, lithium-sulfur batteries hold great potential to become the mainsiay of next-generation energy storage system. Regarding the composition of ...Due to the high specific capacity, low cost, and environmental friendliness, lithium-sulfur batteries hold great potential to become the mainsiay of next-generation energy storage system. Regarding the composition of sulfur/carbon in cathode, flammable organic liquid electrolyte, and lithium metal anode, great concerns about the safety have been raised. Hence solid-electrolyte-based lithium-sulfur batteries, as one alternative route for safe batteries, are highly interested. This review highlights the recent research progress of lithium-sulfur batteries with solid electrolytes. Both sulfide solid electrolytes and oxide solid electrolytes are included. The sulfide solid electrolytes are mainly employed in all-solid-state lithium-sulfur batteries, while the oxide solid electrolytes are applied in hybrid electrolyte for lithium-sulfur batteries. The challenges and perspectives in this field are also featured on the basis of its current progress.展开更多
文摘In the present work, novel blend polymer electrolyte membranes using poly(vinyl alcohol) (PVA), doped with hypophosphorous acid (H3PO2) and reinforced with porous niobium oxide (Nb2O5) microparticles in different compositions were prepared by the solution-casting technique. Their phase behavior and ionic conductivity were studied by differential scanning calorimetric (DSC), thermogravimetric analysis (TGA) and impedance spectroscopy (IS) in the radio-frequency range. Using a constant H3PO2/PVA weigh ratio of 0.25, it was found that the water content in the blended hydrogel membranes increased with increasing the filler Nb2O5 content, thus increasing the electrical conductivity. However, the suitable weight ratio of Nb2O5:(H3PO2/PVA) for the blend performance (both mechanically and electrically) was x = 0.075, with a maximum ionic conductivity of 2.7?× 10﹣3 S·cm﹣1 at 120°C. For all blends prepared, the lost tangent plots show asymmetrical peaks, as a consequence of correlations in the mobile ion diffusion as a function of frequency. Although this “universal dynamic response” was observed at all temperatures, variations in the tan(δ) relaxation peaks indicate a decrease of ionic correlation when the temperature is increased. Both the dc conductivity and tan(δ) peaks frequency dependency are thermally activated, following an Arrhenius-type behavior with activation energy of the same order, indicating that the corresponding ionic processes have the same origin, i.e., proton jump among available sites in the polymer matrix. The additions of oxide particles to the membranes improve their thermal and electrical properties, attributed to an approximation effect.
基金Project supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions,P.R.Chinathe Program for Changjiang Scholars and Innovative Research Teams in Universities(PCSIRT,IRT_15R35)
文摘The nanocomposite electrolytes composed of Smo.2Ce0.801.9 （SDC） nanorods enclosed by { 110} and { 100} facets and a binary carbonate （（Lio.52Nao.48）2CO3, LNC） were prepared by a wet mixing method to investigate the conduction mechanism. The X-ray diffraction （XRD）, scanning electron microscopy （FESEM） and transmission electron microscopy （TEM） techniques were em- ployed to characterize the phase components and microstructures of SDC nanorods and SDC nanorods/LNC composite electrolytes. X-ray powder diffraction showed that a well-cubic fluorite structure was formed. The AC impedance spectroscopy and DC polariza- tion method were used to measure the electrical conductivities of nanocomposite electrolytes under different conditions. The overall ionic conductivities of nanocomposite electrolytes in the air and hydrogen atmospheres were measured up to 82 and 96 mS/cm at 650 ℃, respectively. Additionally, the protonic and oxide ionic conductivities of nanocomposite electrolytes were found to reach 20 and 18 mS/cm at 650 ℃, respectively. The conduction mechanism was discussed in detail by comparing the conductivities of nanocom- posite electrolytes. The protonic conductivity of SDC nanorods/LNC nanocomposite was higher than oxide ionic conductivity. The melt of LNC and the interface layer may make a dominant contribution to oxide ions and protonic conductivity in air and hydrogen atmosphere, respectively.
文摘The conductivity of the solid electrolyte based on urea and thiourea has reached 6. 84 × 10-3 S. cm-1 at room temperature. Analysing the conductive process of this electrolyte we found that thiourea changes into ammonium thiocyanate at a high temperature, which ionizes into ions, and can conduct the current. We obtained a red color substance through electrolysing the SPE. Analysing it with IR, UV and FAB, we confirmed that it is a polymer with a structure (SCN)n. It is proved that the aninon is SCN-. When weadded HCl into the acetone solution of the SPE, it was found that white precipitation material appeared in the solution, which was identified as NH4Cl, so the canon is NH4+.
基金supported by the National Key Research and Development Program (2016YFA0202500, 2015CB932500)the National Natural Science Foundation of China (21676160, 21776019)
文摘Due to the high specific capacity, low cost, and environmental friendliness, lithium-sulfur batteries hold great potential to become the mainsiay of next-generation energy storage system. Regarding the composition of sulfur/carbon in cathode, flammable organic liquid electrolyte, and lithium metal anode, great concerns about the safety have been raised. Hence solid-electrolyte-based lithium-sulfur batteries, as one alternative route for safe batteries, are highly interested. This review highlights the recent research progress of lithium-sulfur batteries with solid electrolytes. Both sulfide solid electrolytes and oxide solid electrolytes are included. The sulfide solid electrolytes are mainly employed in all-solid-state lithium-sulfur batteries, while the oxide solid electrolytes are applied in hybrid electrolyte for lithium-sulfur batteries. The challenges and perspectives in this field are also featured on the basis of its current progress.
