Zr0.5Ti0.5O2(ZT) and Zr0.25Ti0.25Al0.5O2(ZTA) mixed oxides were prepared by co-precipitation method and characterized by low temperature adsorption-desorption,XRD and NH3-TPD. The activity of Pt/Zr0.5Ti0.5O2 and Pt/ Z...Zr0.5Ti0.5O2(ZT) and Zr0.25Ti0.25Al0.5O2(ZTA) mixed oxides were prepared by co-precipitation method and characterized by low temperature adsorption-desorption,XRD and NH3-TPD. The activity of Pt/Zr0.5Ti0.5O2 and Pt/ Zr0.5Ti0.5Al0.5O2 catalysts was evaluated using the simulated gases. The results show that ZTA samples exhibit higher specific surface area,larger pore volume and proper surface acidic amount and acidity in comparison with ZT. The results of the catalytic test indicate that Pt/ZT and Pt/ZTA catalysts exhibit excellent low-temperature catalytic activity and lower light-off temperatures of hydrocarbon,carbon monoxide and nitrogen oxides,especially better conversion for nitrogen oxides (NOx). The addition of Al2O3 into ZT enhanced the anti-aging property of Pt/ ZTA catalysts due to the excellent textural,structural,surface acidity and thermal stability.展开更多
采用化学共沉淀法预先合成球形前驱体Ni0.5Co0.2Mn0.3（OH）2,再与锂源共混后高温煅烧合成高容量正极材料Li Ni0.5Co0.3Mn0.2O2。探讨了不同烧结制度对材料结构性能的影响。X射线衍射（XRD）结果表明,产物结构为α-Na Fe O2型层状结构...采用化学共沉淀法预先合成球形前驱体Ni0.5Co0.2Mn0.3（OH）2,再与锂源共混后高温煅烧合成高容量正极材料Li Ni0.5Co0.3Mn0.2O2。探讨了不同烧结制度对材料结构性能的影响。X射线衍射（XRD）结果表明,产物结构为α-Na Fe O2型层状结构。扫描电子显微镜（SEM）显示材料具有良好的球形形貌。测试材料的电化学性能,在2.75~4.20 V和2.75~4.35 V充放电截止电压,0.5 C充放电电流下,首次放电比容量分别为162.2和172.6 m Ah/g,循环3周后容量保持率分别为96.73%和94.62%。材料还表现出良好的倍率性能。展开更多
Layered Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) cathode materials for lithium-ion batteries were synthesized by one step solid-state method using Ni(OH)2, MnCO3, Li2CO3, TiO2 and Al(OH)3 as starting materials. The...Layered Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) cathode materials for lithium-ion batteries were synthesized by one step solid-state method using Ni(OH)2, MnCO3, Li2CO3, TiO2 and Al(OH)3 as starting materials. The effect of Ti and Al doping on the structure and electrochemical performance of Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) has been investigated. LiNi0.5Mn0.5O2, Li(Ni0.5Mn0.5)0.98Ti0.02O2 and Li(Ni0.5Mn0.5)0.98Al0.02O2 delivered 149 mAh·g-1, 160 mAh·g-1, 164 mAh·g-1, respectively, at a current of 20 mA·g-1 between 2.5 V and 4.3 V at room temperature, and remained 86%, 91%, 91% of the initial discharge capacity respectively after 30 cycles. AC impedance studies show that Ti and Al doping in Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) decreased the resistance of charge transfer Rct of cathode materials.展开更多
文摘Zr0.5Ti0.5O2(ZT) and Zr0.25Ti0.25Al0.5O2(ZTA) mixed oxides were prepared by co-precipitation method and characterized by low temperature adsorption-desorption,XRD and NH3-TPD. The activity of Pt/Zr0.5Ti0.5O2 and Pt/ Zr0.5Ti0.5Al0.5O2 catalysts was evaluated using the simulated gases. The results show that ZTA samples exhibit higher specific surface area,larger pore volume and proper surface acidic amount and acidity in comparison with ZT. The results of the catalytic test indicate that Pt/ZT and Pt/ZTA catalysts exhibit excellent low-temperature catalytic activity and lower light-off temperatures of hydrocarbon,carbon monoxide and nitrogen oxides,especially better conversion for nitrogen oxides (NOx). The addition of Al2O3 into ZT enhanced the anti-aging property of Pt/ ZTA catalysts due to the excellent textural,structural,surface acidity and thermal stability.
文摘采用化学共沉淀法预先合成球形前驱体Ni0.5Co0.2Mn0.3（OH）2,再与锂源共混后高温煅烧合成高容量正极材料Li Ni0.5Co0.3Mn0.2O2。探讨了不同烧结制度对材料结构性能的影响。X射线衍射（XRD）结果表明,产物结构为α-Na Fe O2型层状结构。扫描电子显微镜（SEM）显示材料具有良好的球形形貌。测试材料的电化学性能,在2.75~4.20 V和2.75~4.35 V充放电截止电压,0.5 C充放电电流下,首次放电比容量分别为162.2和172.6 m Ah/g,循环3周后容量保持率分别为96.73%和94.62%。材料还表现出良好的倍率性能。
文摘Layered Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) cathode materials for lithium-ion batteries were synthesized by one step solid-state method using Ni(OH)2, MnCO3, Li2CO3, TiO2 and Al(OH)3 as starting materials. The effect of Ti and Al doping on the structure and electrochemical performance of Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) has been investigated. LiNi0.5Mn0.5O2, Li(Ni0.5Mn0.5)0.98Ti0.02O2 and Li(Ni0.5Mn0.5)0.98Al0.02O2 delivered 149 mAh·g-1, 160 mAh·g-1, 164 mAh·g-1, respectively, at a current of 20 mA·g-1 between 2.5 V and 4.3 V at room temperature, and remained 86%, 91%, 91% of the initial discharge capacity respectively after 30 cycles. AC impedance studies show that Ti and Al doping in Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) decreased the resistance of charge transfer Rct of cathode materials.
