نتایج جستجو برای: orr
تعداد نتایج: 3477 فیلتر نتایج به سال:
Oxygen reduction reaction (ORR) is investigated on bulk PdO-based catalysts (oxides of Pd and Pd3Co) in oxygen-saturated 0.1 M HClO4 to establish the role of surface oxides and adsorbed hydrogen in the activity and product selectivity (H2O/H2O2). The initial voltammetric features suggest that the oxides are inactive toward ORR. The evolution of the ORR voltammograms and potential-dependent H2O2...
Nanostructured Pt-metal alloys have shown impressive catalytic properties for the oxygen reduction reaction (ORR) in acidic medium, but their long-term stability has not been satisfactory. Herein, we look beyond the traditional Pt-metal alloys and have developed a new kind of Pt-nonmetal alloy electrocatalyst for the ORR. Specifically, the novel catalyst is composed of interconnected platinum m...
The high cost of the platinum-based cathode catalysts for the oxygen reduction reaction (ORR) has impeded the widespread application of polymer electrolyte fuel cells. We report on a new family of non-precious metal catalysts based on ordered mesoporous porphyrinic carbons (M-OMPC; M = Fe, Co, or FeCo) with high surface areas and tunable pore structures, which were prepared by nanocasting mesop...
By one-step pyrolysis of a unique "cage-in-cage" cobalt metal-organic framework, nitrogen-doped carbon cubes embedded with numerous metallic Co nanoparticles were obtained. A considerable amount of Co particles was encapsulated in thin carbon shells and formed the core-shell-like Co@C structure. With about 60 wt% Co particles in the prepared sample, the nanocomposites of Co nanoparticles and ni...
AIM This retrospective study of patients in the USA with metastatic Merkel cell carcinoma (mMCC) aimed to assess patient responses to second-line and later (2L+) and first-line (1L) chemotherapy. PATIENTS & METHODS Out of 686 patients with MCC identified in The US Oncology Network, 20 and 67 patients with mMCC qualified for the 2L+ and 1L study, respectively; the primary analysis population w...
The widespread use of low-temperature polymer electrolyte membrane fuel cells for mobile applications will require significant reductions in the amount of expensive Pt contained within their cathodes, which drive the oxygen reduction reaction (ORR). Although progress has been made in this respect, further reductions through the development of more active and stable electrocatalysts are still ne...
Nanostructured Pt-metal alloys have shown impressive catalytic properties for the oxygen reduction reaction (ORR) in acidic medium, but their long-term stability has not been satisfactory. Herein, we look beyond the traditional Pt-metal alloys and have developed a new kind of Pt-nonmetal alloy electrocatalyst for the ORR. Specifically, the novel catalyst is composed of interconnected platinum m...
A series of batch and column laboratory experiments were conducted to determine adsorption coefficients of mercury (II) for Oak Ridge Reservation (ORR) soil. The experimental setup used soil collected from an area offsite of the ORR, in a location upstream of East Fork Poplar Creek (EFPC). The batch equilibrium experiments were conducted in the range of 600 to 5,000 μg/L of initial Hg(II) conce...
Carbon-supported platinum (Pt) and palladium (Pd) alloy catalyst has become a promising alternative electrocatalyst for oxygen reduction reaction (ORR) in proton exchange membrane fuel cells. In this work, the synthesis of highly active and stable carbon-supported Pt-Pd alloy catalysts is reported with a room-temperature electron reduction method. The alloy nanoparticles thus prepared show a pa...
The project was launched on September 15, 2009. Over the grant period, we have accomplished all the research objectives proposed in the proposal. Specifically, we have developed and performed Monte Carlo (MC) simulations predicting the surface composition of a series of Pt binary and ternary alloy catalysts, carried out first-principles transition state calculations of the ORR on Pt and Pt allo...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید