Palladium-supported cobalt hydroxide(Co(OH)_(2)-Pd) nanoplates were fabricated in an aqueous solution and employed as a catalyst for the reduction of 4-nitrophenol.For the preparation of Co(OH)2-Pd,Pd nanoparticles we...Palladium-supported cobalt hydroxide(Co(OH)_(2)-Pd) nanoplates were fabricated in an aqueous solution and employed as a catalyst for the reduction of 4-nitrophenol.For the preparation of Co(OH)2-Pd,Pd nanoparticles were anchored on the Co(OH)_(2) nanoplates after the reduction of Na;PdCl;by ascorbic acid in the absence of a stabilizer at room temperature.The observations under transmission and scanning electron microscopy reveal that Pd nanoparticles with a size of 2-5 nm are uniformly dispersed on the surface of the Co(OH)_(2) nanoplates.In catalytic test,the conversion of 4-nitrophenol to 4-aminophenol is completed within 6 min in the presence of Co(OH)_(2)-Pd(1000) nanoplates with2.18 at.% Pd,and the corresponding kinetic constant is 0.0089 s;in the first test.The catalyst retains relatively high activity after several cycles.The results demonstrate that the Co(OH)_(2)-Pd(1000) nanoplates exhibit high catalytic activity toward the reduction of 4-nitrophenol in the presence of NaBH;.展开更多
β-Co（OH）2 and Mg（OH）2 nanoplates were synthesized via a facile template-free hydrothermal approach.The different conditions of preparation and catalytic properties of the products were studied and discussed.The p...β-Co（OH）2 and Mg（OH）2 nanoplates were synthesized via a facile template-free hydrothermal approach.The different conditions of preparation and catalytic properties of the products were studied and discussed.The products were characterized by X-ray diffraction,transmission electron microscopy,scanning electron microscopy,selected area electron diffraction（SAED）,and gas chromatograph.展开更多
氢氧化镍是碱性蓄电池的正极活性物质,为了改善镍系列电池的性能,合成了掺杂α Ni(OH)2,它具有较高的放电平台,且放电曲线平坦,放电容量高,在碱性溶液中结构稳定。对它进行了电极性能研究。通过循环伏安法,结合Ran dle Sevick方程,得出...氢氧化镍是碱性蓄电池的正极活性物质,为了改善镍系列电池的性能,合成了掺杂α Ni(OH)2,它具有较高的放电平台,且放电曲线平坦,放电容量高,在碱性溶液中结构稳定。对它进行了电极性能研究。通过循环伏安法,结合Ran dle Sevick方程,得出了质子扩散系数为2.35×10-10cm2/s;通过交流阻抗法发现它由电化学极化阻抗和Warburg阻抗组成。展开更多
基金the financial supports from the National Natural Science Foundation of China (Nos. 51974116, 51874128)the Science Foundation of Hunan Province, China (Nos. 2020JJ4273, 2020JJ5130)。
文摘Palladium-supported cobalt hydroxide(Co(OH)_(2)-Pd) nanoplates were fabricated in an aqueous solution and employed as a catalyst for the reduction of 4-nitrophenol.For the preparation of Co(OH)2-Pd,Pd nanoparticles were anchored on the Co(OH)_(2) nanoplates after the reduction of Na;PdCl;by ascorbic acid in the absence of a stabilizer at room temperature.The observations under transmission and scanning electron microscopy reveal that Pd nanoparticles with a size of 2-5 nm are uniformly dispersed on the surface of the Co(OH)_(2) nanoplates.In catalytic test,the conversion of 4-nitrophenol to 4-aminophenol is completed within 6 min in the presence of Co(OH)_(2)-Pd(1000) nanoplates with2.18 at.% Pd,and the corresponding kinetic constant is 0.0089 s;in the first test.The catalyst retains relatively high activity after several cycles.The results demonstrate that the Co(OH)_(2)-Pd(1000) nanoplates exhibit high catalytic activity toward the reduction of 4-nitrophenol in the presence of NaBH;.
基金Supported by the National Natural Science Foundation of China(Nos.20331010,20671011,90406024and90406002)the 111 Project(No.B07012)the Key Laboratory of Structural Chemistry Foundation(No.060017).
文摘β-Co（OH）2 and Mg（OH）2 nanoplates were synthesized via a facile template-free hydrothermal approach.The different conditions of preparation and catalytic properties of the products were studied and discussed.The products were characterized by X-ray diffraction,transmission electron microscopy,scanning electron microscopy,selected area electron diffraction（SAED）,and gas chromatograph.
文摘氢氧化镍是碱性蓄电池的正极活性物质,为了改善镍系列电池的性能,合成了掺杂α Ni(OH)2,它具有较高的放电平台,且放电曲线平坦,放电容量高,在碱性溶液中结构稳定。对它进行了电极性能研究。通过循环伏安法,结合Ran dle Sevick方程,得出了质子扩散系数为2.35×10-10cm2/s;通过交流阻抗法发现它由电化学极化阻抗和Warburg阻抗组成。
