Graphene oxide(GO)with excellent dispersion ability can assist the dispersion of single-walled carbon nanotube(SWCNT)and promote the formation of uniform and stable GO/SWCNT coating liquid.The highly conductive polyet...Graphene oxide(GO)with excellent dispersion ability can assist the dispersion of single-walled carbon nanotube(SWCNT)and promote the formation of uniform and stable GO/SWCNT coating liquid.The highly conductive polyethylene terephthalate/reduced graphene oxide/SWCNT(PET/rGO/SWCNT)electromagnetic shielding composite fabric was successfully prepared by anchoring rGO/SWCNT on PET fabric via dip-coating piror to low-temperature thermal reduction.The results showed that the carboxyl groups and hydroxyl groups formed of hydrophilic-treated PET were conducive to the formation of hydrogen bonds with that of GO,which enhanced the interaction between PET fabric and GO/SWCNT coating;the loading of GO/SWCNT increased with the number of dip-coating,the unit area loading of rGO/SWCNT in the final composite fabric was 2.7 mg/cm^(2) after 10 dip-coating cycles and thermal reduction;the PET/rGO/SWCNT composite fabric had a continuous and dense conductive network,with a conductivity of up to 41.6 S/m and the average electromagnetic interference shielding effectiveness in X-band was 22 dB;the flexible PET/rGO/SWCNT composite fabric was not only easy to process,but also exhibited excellent conductivity and shielding efficiency,showing great potential in the application of electromagnetic shielding fabrics.展开更多
Aluminum spent potlining (SPL) was employed as both the fluxing agent and a source of carbonaceous reductant for the carbothermic reduction of chromite, aiming to allow effective separation of alloy from the slag comp...Aluminum spent potlining (SPL) was employed as both the fluxing agent and a source of carbonaceous reductant for the carbothermic reduction of chromite, aiming to allow effective separation of alloy from the slag component. The experimental results show that the carbonaceous component of the SPL is more reactive towards chromite reduction compared to graphite. The formation of refractory spinel (MgAl2O4) on chromite particles hinders further reduction and alloy growth. The slag-making components of the SPL (e.g. nepheline and NaF) form molten slags at low temperatures (~1300℃) and partly dissolve the refractory spinel as well as the chromite. Destruction of the spinel layer with enhanced mass transfer greatly improves the alloy growth, which can be further promoted by reduction at a higher temperature (e.g. 1500℃). Ferrochrome alloy particles grow large enough at 1500℃ in the presence of SPL, allowing effective separation from the slag component using elutriation separation.展开更多
The V2O3-C dual-layer coated LiFePO4 cathode materials with excellent rate capability and cycling stability were prepared by carbothermic reduction of V2O5. X-ray powder diffraction, elemental analyzer, high resolutio...The V2O3-C dual-layer coated LiFePO4 cathode materials with excellent rate capability and cycling stability were prepared by carbothermic reduction of V2O5. X-ray powder diffraction, elemental analyzer, high resolution transmission electron microscopy and Raman spectra revealed that the V2O3 phase co-existed with carbon in the coating layer of LiFePO4 particles and the carbon content reduced without graphitization degree changing after the carbothermic reduction of V205. The electrochemical measurement results indicated that small amounts of V203 improved rate capability and cycling stability at elevated temperature of LiFePO4/C cathode materials. The V203-C dual-layer coated LiFePO4 composite with lwt% vanadium oxide delivered an initial specific capacity of 167 mAh/g at 0.2 C and 129 mAh/g at 5 C as well as excellent cycling stability. Even at elevated temperature of 55 ℃, the specific capacity of 151 mAh/g was achieved at 1 C without capacity fading after 100 cycles.展开更多
To make sure the intermediate products of the carbothermic reduction of Al2O3 process, such as Al4CO4, Al2CO and Al4C3,and the interaction of AlCl, AlCl2, AlCl3 with Al4CO4, Al2CO and Al4C3, respectively, thermodynami...To make sure the intermediate products of the carbothermic reduction of Al2O3 process, such as Al4CO4, Al2CO and Al4C3,and the interaction of AlCl, AlCl2, AlCl3 with Al4CO4, Al2CO and Al4C3, respectively, thermodynamic analyses were used to study the chloride reaction production of them under the vacuum situation. The stable structures and electronic properties of AlCl, AlCl2 and AlCl3 adsorbed on Al4CO4, Al2CO and Al4C3 were calculated by first-principles calculations by the CASTEP module in the Materials Studio program. The results show that the AlCl3 and AlCl2 molecules have decomposed on the plane of Al4C3(001), while there are no obvious decomposition of AlCl3 and AlCl2 on Al4CO4(001) and Al2CO(001) planes. The adsorption of AlCl on the Al4CO4(001)and Al2CO(001) planes is stronger than that on the Al4C3(001) plane. The interaction strength of AlCl3, as well as AlCl2, with Al4CO4,Al2CO and Al4C3 is in the sequence of Al4CO4Al2CO〉Al4C3.展开更多
文摘Graphene oxide(GO)with excellent dispersion ability can assist the dispersion of single-walled carbon nanotube(SWCNT)and promote the formation of uniform and stable GO/SWCNT coating liquid.The highly conductive polyethylene terephthalate/reduced graphene oxide/SWCNT(PET/rGO/SWCNT)electromagnetic shielding composite fabric was successfully prepared by anchoring rGO/SWCNT on PET fabric via dip-coating piror to low-temperature thermal reduction.The results showed that the carboxyl groups and hydroxyl groups formed of hydrophilic-treated PET were conducive to the formation of hydrogen bonds with that of GO,which enhanced the interaction between PET fabric and GO/SWCNT coating;the loading of GO/SWCNT increased with the number of dip-coating,the unit area loading of rGO/SWCNT in the final composite fabric was 2.7 mg/cm^(2) after 10 dip-coating cycles and thermal reduction;the PET/rGO/SWCNT composite fabric had a continuous and dense conductive network,with a conductivity of up to 41.6 S/m and the average electromagnetic interference shielding effectiveness in X-band was 22 dB;the flexible PET/rGO/SWCNT composite fabric was not only easy to process,but also exhibited excellent conductivity and shielding efficiency,showing great potential in the application of electromagnetic shielding fabrics.
基金funded by NRCan under the Rare Earth Elements and Chromite R&D Program
文摘Aluminum spent potlining (SPL) was employed as both the fluxing agent and a source of carbonaceous reductant for the carbothermic reduction of chromite, aiming to allow effective separation of alloy from the slag component. The experimental results show that the carbonaceous component of the SPL is more reactive towards chromite reduction compared to graphite. The formation of refractory spinel (MgAl2O4) on chromite particles hinders further reduction and alloy growth. The slag-making components of the SPL (e.g. nepheline and NaF) form molten slags at low temperatures (~1300℃) and partly dissolve the refractory spinel as well as the chromite. Destruction of the spinel layer with enhanced mass transfer greatly improves the alloy growth, which can be further promoted by reduction at a higher temperature (e.g. 1500℃). Ferrochrome alloy particles grow large enough at 1500℃ in the presence of SPL, allowing effective separation from the slag component using elutriation separation.
基金This work was supported by the National Natural Science Foundation of China (No.21006033 and No.51372060) and the Fundamental Research fUnds for the Central Universities (No.2013HGCH0002).
文摘The V2O3-C dual-layer coated LiFePO4 cathode materials with excellent rate capability and cycling stability were prepared by carbothermic reduction of V2O5. X-ray powder diffraction, elemental analyzer, high resolution transmission electron microscopy and Raman spectra revealed that the V2O3 phase co-existed with carbon in the coating layer of LiFePO4 particles and the carbon content reduced without graphitization degree changing after the carbothermic reduction of V205. The electrochemical measurement results indicated that small amounts of V203 improved rate capability and cycling stability at elevated temperature of LiFePO4/C cathode materials. The V203-C dual-layer coated LiFePO4 composite with lwt% vanadium oxide delivered an initial specific capacity of 167 mAh/g at 0.2 C and 129 mAh/g at 5 C as well as excellent cycling stability. Even at elevated temperature of 55 ℃, the specific capacity of 151 mAh/g was achieved at 1 C without capacity fading after 100 cycles.
基金Projects(51104078,51264023)supported by the National Natural Science Foundation of ChinaProject(2010CD022)supported by Yunnan Provincial Applied Basic Research Fund,China+2 种基金Project(IRT1250)supported by the Program for Innovative Research Team in University of Ministry of Education of ChinaProject(U1202271)supported by the National Natural Science Foundation of China-Yunnan United FundProject(KKZ3201252020)supported by Fund of Kunming University of Science and Technology for Talent Training,China
文摘To make sure the intermediate products of the carbothermic reduction of Al2O3 process, such as Al4CO4, Al2CO and Al4C3,and the interaction of AlCl, AlCl2, AlCl3 with Al4CO4, Al2CO and Al4C3, respectively, thermodynamic analyses were used to study the chloride reaction production of them under the vacuum situation. The stable structures and electronic properties of AlCl, AlCl2 and AlCl3 adsorbed on Al4CO4, Al2CO and Al4C3 were calculated by first-principles calculations by the CASTEP module in the Materials Studio program. The results show that the AlCl3 and AlCl2 molecules have decomposed on the plane of Al4C3(001), while there are no obvious decomposition of AlCl3 and AlCl2 on Al4CO4(001) and Al2CO(001) planes. The adsorption of AlCl on the Al4CO4(001)and Al2CO(001) planes is stronger than that on the Al4C3(001) plane. The interaction strength of AlCl3, as well as AlCl2, with Al4CO4,Al2CO and Al4C3 is in the sequence of Al4CO4Al2CO〉Al4C3.