Nanometer Cu singly doped and Cu/Al co-doped nickel hydroxides were synthesized by ultrasonic-assisted precipitation method. Their crystal structure, particle size, morphology, tap density and electrochemical performa...Nanometer Cu singly doped and Cu/Al co-doped nickel hydroxides were synthesized by ultrasonic-assisted precipitation method. Their crystal structure, particle size, morphology, tap density and electrochemical performance were investigated. The results show that the samples have a-phase structure with narrow particle size distribution. Cu singly doped nano-Ni（OH）2 contains irregular particles, while Cu/Al co-doped nano-Ni（OH）2 displays a quasi-spherical shape and has a relatively higher tap density. Composite electrodes were prepared by mixing 8% （mass fraction） nanometer samples with commercial micro-size spherical nickel. The charge/discharge test and cyclic voltammetry results indicate that the electrochemical performance of Cu/Al co-doped nano-Ni（OH）2 is better than that of Cu singly doped nano-Ni（OH）2, the former＇s discharge capacity reaches 330 mA.h/g at 0.2C, 12 mA.h/g and 91 mA.h/g larger than that of Cu singly doped sample and pure spherical nickel electrode, respectively. Moreover, the proton diffusion coefficient of Cu/Al co-doped sample is 52.3% larger than that of Cu singly doped sample.展开更多
In order to obtain nanomaterials with superparamagnetism and high saturation magnetization, Mn-doped or Zn-doped superparamagnetic ferrite nanoclusters(Mn-FNs or Zn-FNs) were prepared by microwave-assisted solvotherma...In order to obtain nanomaterials with superparamagnetism and high saturation magnetization, Mn-doped or Zn-doped superparamagnetic ferrite nanoclusters(Mn-FNs or Zn-FNs) were prepared by microwave-assisted solvothermal method in this study. Preliminary investigations were performed by transmission electron microscopy(TEM) and dynamic light scattering(DLS) instrument to observe the morphology and measure the particle size, respectively. Afterwards, Zn-FNs were chosen to be further characterized in vitro due to their better morphology and dispersity than Mn-FNs. The subsequent characterizations included crystalline phase, metal content and magnetic properties by X-ray diffractometer(XRD), inductively coupled plasma-mass spectrometry(ICP-MS) and vibrating sample magnetometer(VSM), respectively. The results showed that Zn-FNs had a cluster-like structure assembled by multiple nanoparticles. Zn-FNs were spherical in shape with good dispersity and relatively uniform particle size. Zn was successfully doped in Zn-FNs which demonstrated spinel structure and excellent magnetic properties. Therefore, Zn-FNs had a favorable application prospect as a new type of magnetic nanomaterial.展开更多
基金Project (10774030) supported by the National Natural Science Foundation of ChinaProject (S2012010009955) supported by the Guangdong Province Natural Science Foundation of ChinaProject (12C232111916) supported by the Science and Technology Program of Guangzhou City of China
文摘Nanometer Cu singly doped and Cu/Al co-doped nickel hydroxides were synthesized by ultrasonic-assisted precipitation method. Their crystal structure, particle size, morphology, tap density and electrochemical performance were investigated. The results show that the samples have a-phase structure with narrow particle size distribution. Cu singly doped nano-Ni（OH）2 contains irregular particles, while Cu/Al co-doped nano-Ni（OH）2 displays a quasi-spherical shape and has a relatively higher tap density. Composite electrodes were prepared by mixing 8% （mass fraction） nanometer samples with commercial micro-size spherical nickel. The charge/discharge test and cyclic voltammetry results indicate that the electrochemical performance of Cu/Al co-doped nano-Ni（OH）2 is better than that of Cu singly doped nano-Ni（OH）2, the former＇s discharge capacity reaches 330 mA.h/g at 0.2C, 12 mA.h/g and 91 mA.h/g larger than that of Cu singly doped sample and pure spherical nickel electrode, respectively. Moreover, the proton diffusion coefficient of Cu/Al co-doped sample is 52.3% larger than that of Cu singly doped sample.
基金National Natural Science Foundation of China(Grant No.81571779).
文摘In order to obtain nanomaterials with superparamagnetism and high saturation magnetization, Mn-doped or Zn-doped superparamagnetic ferrite nanoclusters(Mn-FNs or Zn-FNs) were prepared by microwave-assisted solvothermal method in this study. Preliminary investigations were performed by transmission electron microscopy(TEM) and dynamic light scattering(DLS) instrument to observe the morphology and measure the particle size, respectively. Afterwards, Zn-FNs were chosen to be further characterized in vitro due to their better morphology and dispersity than Mn-FNs. The subsequent characterizations included crystalline phase, metal content and magnetic properties by X-ray diffractometer(XRD), inductively coupled plasma-mass spectrometry(ICP-MS) and vibrating sample magnetometer(VSM), respectively. The results showed that Zn-FNs had a cluster-like structure assembled by multiple nanoparticles. Zn-FNs were spherical in shape with good dispersity and relatively uniform particle size. Zn was successfully doped in Zn-FNs which demonstrated spinel structure and excellent magnetic properties. Therefore, Zn-FNs had a favorable application prospect as a new type of magnetic nanomaterial.
