ABSTRACT
G-C3N4 has a bright application prospect as an electrode material of supercapacitors, which makes it a concern. In order to increase the specific capacitance of g-C3N4, we consider to combine it with a metal oxide with high theoretical specific capacitance and utilize the synergistic effect. As a common metal oxide, CuO has the characteristics of high theoretical capacitance, high chemical stability, simple preparation and environmental friendliness. A composite containing CuO nanobelts and graphitic C3N4 (g-C3N4) was successfully synthesized by a chemical precipitation method. Various testing methods were used to explore its composition, microstructure and electrochemical properties to discuss whether CuO is suitable for improving the electrochemical properties of g-C3N4.
ABSTRACT
Commercial WS2 powders were exfoliated in sodium dodecyl sulfate solution with a combination of ball-milling and sonication. WS2 nanosheets can be uniformly dispersed in the solution. The layers and thicknesses of WS2 nanosheets could be tailored via changing the ball-milling speed. The effects of the ball-milling speed on crystallinity and morphology of the samples were analyzed. The results show that the layer structure of WS2 nanosheets is destroyed and the crystallinity is decreased with increase of the ball-milling rate. The monolayer WS2 nanosheets at 200 rpm are obtained, which are mesoporous with the specific surface area as 5.419 m2 g-1. The specific capacitance and charge/discharge efficiency of WS2 nanosheets at 200 rpm are better than those of other samples. Its specific capacitance under the scanning rate of 20 mV s-1 and the current density of 0.5 A g-1 are 13.46 F g-1 and 22.50 F g-1, respectively. The charge/discharge curve of WS2 nanosheets at 200 rpm is a symmetrical triangle, which shows rapid charge and slow discharge. It means that WS2 nanosheets at 200 rpm has good electrochemical reversibility. The load transfer resistance and the internal series resistance of this sample are 84.60 Ω and 4.18 Ω, respectively.
ABSTRACT
We have established the micro-magnetic field on the surfaces of 316L stainless steel and NiTi alloy through the magnetization process of sol-gel prepared TiO(2) thin film with the powder of SrFe(12)O(19). The nano-sized with brown color of SrFe(12)O(19) powder was verified by transmission electron microscope. By using X-ray diffraction, surface roughometer, and corrosion experimental test, the deposited thin film can decrease the etching of body fluid as well as prevent the hazardous Ni ions released from the metal. Moreover, with evaluation of dynamic cruor time test and blood platelets adhesion test, we found the micro-magnetic field of the thin film can improve the blood compatibility.
Subject(s)
Blood Coagulation , Coated Materials, Biocompatible , Magnetic Fields , Humans , Materials Testing/methods , Nickel/chemistry , Platelet Adhesiveness , Stainless Steel/chemistry , Surface Properties , Titanium/chemistryABSTRACT
Reaction of Ni[(C4H9O)2PS2]2 with ethylamine, n-propylamine, n-butylamine, and n-amylamine have been studied by spectrophotometry in ethanol at 30 degrees C. For nitrogen base(B), the adduct formation of NiL2.B and NiL2.B2 is established, and their additive equilibrium constants (lg beta n) and molecular number (n) have been discussed. All the NiL2.B and NiL2.B2 complexes exhibit virtually the same electronic spectra arising from the five-coordinate NiNS4 and six-coordinate NiN2S4 chromophore respectively. The constants (lg beta n) increase with basicity (pKa) of nitrogen base and can be described by experimental formulas: lg beta 1 = -9.69 +1.15 pKa; lg beta 2 = -18.73 +2.28 pKa.
