摘要:
The present teachings are directed to preparation of carbon-supported CoSe2 nanoparticles via an in situ surfactant free method, and use of the same for oxygen reduction and hydrogen evolution reactions. The CoSe2 nanoparticles have two kinds of structure after heat treatment at different temperatures: orthorhombic at 300° C. and cubic at 400° C. The latter structure has higher oxygen reduction activity and hydrogen evolution activity than the former in 0.5 M H2SO4. Electron transfers of about 3.5- and about 3.7-electrons were observed for 20 wt. % CoSe2/C nanoparticles, after heat treatment at 300° C. and 400° C., per oxygen molecule during the oxygen reduction process, respectively.
摘要翻译:本教导涉及通过原位不含表面活性剂的方法制备碳载体的CoSe 2纳米颗粒,并将其用于氧还原和析氢反应。 CoSe2纳米颗粒在不同温度下热处理后具有两种结构:300℃为斜方晶,400℃为立方晶。后者结构具有比前者在0.5M H 2 SO 4中更高的氧还原活性和析氢活性。 观察到约3.5-约3.7电子的电子转移为20wt。 在氧还原过程中,分别在每个氧分子在300℃和400℃下热处理之后的CoSe 2 / C纳米颗粒。
摘要:
The present teachings are directed toward electrocatalyst compositions of alloys of platinum, tungsten and nickel for use in fuel cells. The alloys consists essentially of platinum present in an atomic percentage ranging between about 20 percent and about 45 percent, tungsten present in an atomic percentage ranging between about 30 percent and about 70 percent, and nickel present in an atomic percentage ranging between about 5 percent and about 25 percent.
摘要:
Synthesis of nanoparticles with particle size control is provided by the method of using two different metal-containing precursors, a capping component, an optional reducing agent, and then contacting the two precursors with the capping component to form a reaction solution, which is heated to produce first and second metals-containing nanoparticles. By controlling the ratio of the concentration of the capping component to the total concentration of the two metal-containing precursors, the nanoparticles can have diameters ranging between about 1 nm to about 15 nm. A decrease in the concentration of the capping component typically increases the size of the nanoparticles. Preferred compositions include Pt and Co-containing alloy nanoparticles. Controlled synthesis of larger, about 6 nm to about 12 nm, sized nanoparticles can be achieved in a solvent-free reaction process.
摘要:
The present teachings are directed toward electrocatalyst compositions of alloys of platinum, tungsten and one of either of nickel or zirconium for use in fuel cells. The alloys consists essentially of platinum present in an atomic percentage ranging between about 20 percent and about 45 percent, tungsten present in an atomic percentage ranging between about 30 percent and about 70 percent, and one of either nickel present in an atomic percentage ranging between about 5 percent and about 25 percent, or zirconium present in an atomic percentage ranging between about 5 percent and about 40 percent.
摘要:
The present teachings are directed methods of producing tungsten-containing nanoparticles, specifically tungsten nanoparticles and tungsten oxide nanoparticles with an average particle size of less than about five nanometers.
摘要:
A fuel cell catalyst comprising platinum, chromium, and copper, nickel or a combination thereof. In one or more embodiments, the concentration of platinum is less than 50 atomic percent, and/or the concentration of chromium is less than 30 atomic percent, and/or the concentration of copper, nickel, or a combination thereof is at least 35 atomic percent.
摘要:
A substrate having a catalytic surface thereon characterized as a coating of metal oxide and noble metal particles in the nominal diameter size distribution range of 10 micrometers) of hydroxides, carbonates or nitrates of the metals: cerium, aluminum, tin, manganese, copper, cobalt, nickel, praseodymium or terbium particles; and hydroxides, carbonates or nitrates of the noble metals: ruthenium, rhodium, palladium, silver, iridium, platinum and gold onto the substrate. The coating adheres to the surface and provides desirable catalyst properties.
摘要:
A layer manager provides at least two content layers within a user interface window of a software application. A tab manager provides at least two content tabs within at least one of the content layers. A transfer manager is configured to transfer at least one content tab between the at least two content layers.