层状过渡金属氧化物由于其较高的理论比容量和较低的经济成本,被视为一种具有良好应用前景的钠离子电池正极材料。采用溶胶-凝胶法和热处理的方式,制备Ca/Cu共掺杂的铁锰基层状氧化物(O3-Na_(0.9)Ca_(0.05)Fe_(0.45)Mn_(0.45)Cu_(0.1O)_...层状过渡金属氧化物由于其较高的理论比容量和较低的经济成本,被视为一种具有良好应用前景的钠离子电池正极材料。采用溶胶-凝胶法和热处理的方式,制备Ca/Cu共掺杂的铁锰基层状氧化物(O3-Na_(0.9)Ca_(0.05)Fe_(0.45)Mn_(0.45)Cu_(0.1O)_(2))。采用X射线衍射仪(XRD)、场发射扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)等对该O3型铁锰基层状氧化物正极材料进行表征分析。结果表明,在32 mA/g电流密度下该材料具有205.2 m A·h/g的高比容量,循环50圈之后仍具有67.64%的容量保持率,在160 m A/g下循环100圈后依然具有81.4 m A·h/g的放电比容量。由于Ca的掺入,引起Na^(+)空位的增加,并且Cu的掺入提高了Mn的价态,从而提高了Na^(+)的扩散速率,抑制了Mn3+的Jahn-Teller效应,缓解了晶格应力,有效提高了材料的结构稳定性和电化学性能。展开更多
Ba0.5Sr0.5Co0.5Fe0.2O3-σ(BSCF), a new cathode material for solid oxide fuel cell (SOFC), was synthesized by polyacrylicacid (PAA) method. The lattice structures of samples calcined at different temperatures were char...Ba0.5Sr0.5Co0.5Fe0.2O3-σ(BSCF), a new cathode material for solid oxide fuel cell (SOFC), was synthesized by polyacrylicacid (PAA) method. The lattice structures of samples calcined at different temperatures were characterized by XRD, Shrinkage, porosity and pore size of the porous BSCF as a function of sintering temperature were investigated. It was found that the cubic perovskite structure could be formed after calcination at 800 ℃ for 2 h, but not well crystallized as seen from some unknown phases, and the pure cubic perovskite structure was formed after calcination at 1150 ℃ for 2 h. The panicle size of BSCF was less than 1-2 μm. The shrinkage of the porous BSCF increased with sintering temperature, but the opposite was true for the porosity. After sintering at 1100 ℃ for 4 h, the porous BSCF was still in an appropriate structure, with porosity of 29% and electrical conductivity above 400 S·cm^-1.展开更多
A new inorganic-organic hybrid framework microporous material Cd 3(BDC) 0.5(BTC) 2·(DMF)(H 2O)·3DMF·H 3O·H 2O, in which two kinds of carboxylate ligands coordinate with cadmium ions synchronously, ...A new inorganic-organic hybrid framework microporous material Cd 3(BDC) 0.5(BTC) 2·(DMF)(H 2O)·3DMF·H 3O·H 2O, in which two kinds of carboxylate ligands coordinate with cadmium ions synchronously, was obtained under a mild synthesis condition. The titled compound is crystallized in a monoclinic system, space group P2(1)/c with a=1.584 7(7) nm, b=1.426 7(6) nm, c=1.936 3(6) nm, β=113.186(7)°, V=4.024 6(3) nm 3, Z=4, D X=1.947 mg/m 3, M r=1 179.92, μ=1.662 mm -1, F(000)=2 344, R=0.074 8, wR=0.215 1. Three cadmium centers link with each other through BDC or BTC ligand to form a 3-D open framework.展开更多
Ba\-\{0.5\}Sr\-\{0.5\}Co\-\{0.8\}Fe\-\{0.2\}O\-\{3-\%δ\%\} and Ba\-\{0.5\}Sr\-\{0.5\}Co\-\{0.8\}Ti\-\{0.2\}O\-\{3-\%δ\%\} oxides were synthesized by a combined EDTA\|citrate complexing method. The catalytic behavior...Ba\-\{0.5\}Sr\-\{0.5\}Co\-\{0.8\}Fe\-\{0.2\}O\-\{3-\%δ\%\} and Ba\-\{0.5\}Sr\-\{0.5\}Co\-\{0.8\}Ti\-\{0.2\}O\-\{3-\%δ\%\} oxides were synthesized by a combined EDTA\|citrate complexing method. The catalytic behavior of these two oxides with the perovskite structure was studied during the reaction of methane oxidation. The pre\|treatment with methane has different effect on the catalytic activities of both the oxides. The methane pre\|treatment has not resulted in the change of the catalytic activity of BSCFO owing to its excellent reversibility of the perovskite structure resulting from the excellent synergistic interaction between Co and Fe in the oxide. However, the substitution with Ti on Fe\|site in the lattice makes the methane pre\|treatment have an obvious influence on the activity of the formed BSCTO oxide.展开更多
通过甘氨酸硝酸盐法（GNP）合成了钙钛矿型Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF）复合氧化物粉体。经压制、烧结后,得到了BSCF烧结体试样,还通过硝酸溶液浸蚀处理对烧结体试样进行了表面浸蚀处理。采用X射线衍射仪（XRD）对煅烧后的粉体进...通过甘氨酸硝酸盐法（GNP）合成了钙钛矿型Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF）复合氧化物粉体。经压制、烧结后,得到了BSCF烧结体试样,还通过硝酸溶液浸蚀处理对烧结体试样进行了表面浸蚀处理。采用X射线衍射仪（XRD）对煅烧后的粉体进行了相成分分析;采用扫描电子显微镜（SEM）及能谱仪（EDS）对烧结体和表面浸蚀后烧结体样品的微观组织和成分进行了表征;对烧结体的致密度、电导率进行了测试分析,并在自制的氧渗透装置上测定了BSCF钙钛矿膜的透氧量,分析了温度和不同氧分压差等对膜透氧性能的影响。实验结果表明,甘氨酸-硝酸盐法所制备的前驱体粉末在900℃煅烧3 h后可获得具有单一钙钛矿结构的BSCF粉体,1100℃煅烧的BSCF烧结体的电导率在600℃时最大达到38.15 S·cm-1。其透氧量随着温度和氧分压差的升高而增大,且硝酸表面浸蚀处理后,BSCF膜片的透氧性能有明显提高,透氧速率提高1.6~4.5倍。850℃,20%O2-80%N2混合气体/He条件下,浸蚀后的透氧膜片的透氧量达到2.36 m L/cm2·min,而未浸蚀透氧膜片的透氧量仅为1.36 m L/cm2·min。展开更多
文摘层状过渡金属氧化物由于其较高的理论比容量和较低的经济成本,被视为一种具有良好应用前景的钠离子电池正极材料。采用溶胶-凝胶法和热处理的方式,制备Ca/Cu共掺杂的铁锰基层状氧化物(O3-Na_(0.9)Ca_(0.05)Fe_(0.45)Mn_(0.45)Cu_(0.1O)_(2))。采用X射线衍射仪(XRD)、场发射扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)等对该O3型铁锰基层状氧化物正极材料进行表征分析。结果表明,在32 mA/g电流密度下该材料具有205.2 m A·h/g的高比容量,循环50圈之后仍具有67.64%的容量保持率,在160 m A/g下循环100圈后依然具有81.4 m A·h/g的放电比容量。由于Ca的掺入,引起Na^(+)空位的增加,并且Cu的掺入提高了Mn的价态,从而提高了Na^(+)的扩散速率,抑制了Mn3+的Jahn-Teller效应,缓解了晶格应力,有效提高了材料的结构稳定性和电化学性能。
文摘Ba0.5Sr0.5Co0.5Fe0.2O3-σ(BSCF), a new cathode material for solid oxide fuel cell (SOFC), was synthesized by polyacrylicacid (PAA) method. The lattice structures of samples calcined at different temperatures were characterized by XRD, Shrinkage, porosity and pore size of the porous BSCF as a function of sintering temperature were investigated. It was found that the cubic perovskite structure could be formed after calcination at 800 ℃ for 2 h, but not well crystallized as seen from some unknown phases, and the pure cubic perovskite structure was formed after calcination at 1150 ℃ for 2 h. The panicle size of BSCF was less than 1-2 μm. The shrinkage of the porous BSCF increased with sintering temperature, but the opposite was true for the porosity. After sintering at 1100 ℃ for 4 h, the porous BSCF was still in an appropriate structure, with porosity of 29% and electrical conductivity above 400 S·cm^-1.
文摘A new inorganic-organic hybrid framework microporous material Cd 3(BDC) 0.5(BTC) 2·(DMF)(H 2O)·3DMF·H 3O·H 2O, in which two kinds of carboxylate ligands coordinate with cadmium ions synchronously, was obtained under a mild synthesis condition. The titled compound is crystallized in a monoclinic system, space group P2(1)/c with a=1.584 7(7) nm, b=1.426 7(6) nm, c=1.936 3(6) nm, β=113.186(7)°, V=4.024 6(3) nm 3, Z=4, D X=1.947 mg/m 3, M r=1 179.92, μ=1.662 mm -1, F(000)=2 344, R=0.074 8, wR=0.215 1. Three cadmium centers link with each other through BDC or BTC ligand to form a 3-D open framework.
文摘Ba\-\{0.5\}Sr\-\{0.5\}Co\-\{0.8\}Fe\-\{0.2\}O\-\{3-\%δ\%\} and Ba\-\{0.5\}Sr\-\{0.5\}Co\-\{0.8\}Ti\-\{0.2\}O\-\{3-\%δ\%\} oxides were synthesized by a combined EDTA\|citrate complexing method. The catalytic behavior of these two oxides with the perovskite structure was studied during the reaction of methane oxidation. The pre\|treatment with methane has different effect on the catalytic activities of both the oxides. The methane pre\|treatment has not resulted in the change of the catalytic activity of BSCFO owing to its excellent reversibility of the perovskite structure resulting from the excellent synergistic interaction between Co and Fe in the oxide. However, the substitution with Ti on Fe\|site in the lattice makes the methane pre\|treatment have an obvious influence on the activity of the formed BSCTO oxide.
文摘通过甘氨酸硝酸盐法（GNP）合成了钙钛矿型Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF）复合氧化物粉体。经压制、烧结后,得到了BSCF烧结体试样,还通过硝酸溶液浸蚀处理对烧结体试样进行了表面浸蚀处理。采用X射线衍射仪（XRD）对煅烧后的粉体进行了相成分分析;采用扫描电子显微镜（SEM）及能谱仪（EDS）对烧结体和表面浸蚀后烧结体样品的微观组织和成分进行了表征;对烧结体的致密度、电导率进行了测试分析,并在自制的氧渗透装置上测定了BSCF钙钛矿膜的透氧量,分析了温度和不同氧分压差等对膜透氧性能的影响。实验结果表明,甘氨酸-硝酸盐法所制备的前驱体粉末在900℃煅烧3 h后可获得具有单一钙钛矿结构的BSCF粉体,1100℃煅烧的BSCF烧结体的电导率在600℃时最大达到38.15 S·cm-1。其透氧量随着温度和氧分压差的升高而增大,且硝酸表面浸蚀处理后,BSCF膜片的透氧性能有明显提高,透氧速率提高1.6~4.5倍。850℃,20%O2-80%N2混合气体/He条件下,浸蚀后的透氧膜片的透氧量达到2.36 m L/cm2·min,而未浸蚀透氧膜片的透氧量仅为1.36 m L/cm2·min。
