【摘 要】
:
Nitrogen-doped carbon materials as promising oxygen reduction reaction (ORR) electrocatalysts attract great interest in fuel cells and metal-air batteries becau
【机 构】
:
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University
论文部分内容阅读
Nitrogen-doped carbon materials as promising oxygen reduction reaction (ORR) electrocatalysts attract great interest in fuel cells and metal-air batteries because of their relatively high activity,high surface area,high conductivity and low cost.To maximize their catalytic efficiency,rational design of efficient electrocatalysts with rich exposed active sites is highly desired.Besides,due to the complexity of nitrogen species,the identification of active nitrogen sites for ORR remains challenging.Herein,we develop a facile and scalable template method to construct high-concentration nitrogen-doped carbon hollow frameworks (NC),and reveal the effect of different nitrogen species on their ORR activity on basis of experimental analysis and theoretical calculations.The formation mechanism is clearly revealed,including low-pressure vapor superassembly of thin zeolitic imidazolate framework (ZlF-8) shell on ZnO templates,in situ carbonization and template removal.The obtained NC-800 displays better ORR activity compared with other NC-700 and NC-900 samples.Our results indicate that the superior ORR activity of NC-800 is mainly attributed to its content balance of three nitrogen species.The graphitic N and pyrrolic N sites are responsible for lowering the working function,while the pyridinic N and pyrrolic N sites as possible active sites are beneficial for increasing the density of states.
其他文献
The increasing utilization of titanium alloys in marine environments makes their microbiologically influenced corrosion study a timely matter.This work demonstr
Twin crystal structured Al-10 wt.% Mg alloys that were grown over a broad solidification velocity range were prepared and studied for the first time.The high the
Solar-blind deep-ultraviolet (DUV) photodetectors based on Ga2O3 have attracted great attention due to their potential applications for many military and civil
The effect of adding D-fructose to simulated body fluid (SBF) on the corrosion behavior ofAZ31 magnesium (Mg) alloy at 37 ℃ and at a pH of 7.4 was studied by p
Solid solution strengthening is one of the most conventional strategies for optimizing alloys strength,while the corresponding mechanisms can be more complicate
Cyclic deformation behavior of friction-stir-welded dissimilar AA2024-T351 to AA7075-T65 aluminum alloy joints was evaluated via stepwise tests at different str
采用微合金化的设计思路,钢板成分在低C、低碳当量的基础上添加少量的Nb、Ti等微合金化元素,同时在冶炼过程中采用氧化物冶金技术,在TMCP轧制过程中采用针对低碳当量的超快冷
The heterogeneous deformation behavior of austenite and ferrite in the 2205 duplex stainless steel was subjected to multiscale analysis based on the in situ syn
Electricity is an efficient form of energy,and the growing interest in electricity-assisted manufacturing is motivated by its inherent energy saving and reduced
研究了Q345R低合金钢H10Mn2焊丝和SJ101焊剂焊接工艺,结果表明,焊接接头抗拉强度达到517MPa,大于母材最低值490 MPa,-20℃V型低温冲击功吸收值最小值98 J,高于最低要求41 J;