Fe-N Doped Hollow Carbon Nanospheres Linked by Carbon Nanotubes for Oxygen Reduction Reaction

以ZIF-8为模板，通过表面包覆聚多巴胺、同时刻蚀ZIF-8中的Zn2+，形成空心球，在与三氯化铁络合后，经高温碳化和氨气热处理，得到了高比表面积的Fe-N共掺杂的碳纳米管串联的碳纳米空心球催化剂. 氨气不仅刻蚀碳基底提高比表面积，还可还原铁元素形成Fe4N纳米粒子，提升了催化剂对氧还原反应的电催化活性，其氧还原半波电位达0.79 V，仅比商业Pt/C低60 mV，而且其稳定性和耐甲醇性更优于商业Pt/C，展示出良好的燃料电池应用潜力.The development of non-precious metal catalysts for oxygen reduction reaction (ORR) is essential for large-scale application of proton exchange membrane fuel cells. Herein, we present the in situ formed Fe-N doped hollow carbon nanospheres linked by carbon nanotubes composite, synthesized by using ZIF-8 as sacrificed template to form polydopamine (PDA) hollow nanospheres, followed by complexing with FeCl3, high temperature heat-treatment and NH3-etching. ZIF-8 was gradually decomposed simultaneously with PDA coating due to the loss of Zn2+ grabbed by PDA. NH3 etching resulted in the improved surface area, while the reducibility of NH3 resulted in the formation of Fe4N nanoparticles, which benefits the ORR activity of the catalyst. The half-wave potential of the as-prepared of PDA-Fe/N/C-NH3 was 0.79 V, only 60 mV lower than that of commercial Pt/C. The stability and methanol tolerance of PDA-Fe/N/C-NH3 were even superior to that of commercial Pt/C, indicating the good potential of PDA-Fe/N/C-NH3 for the application of fuel cells.黑龙江省自然科学基金（No. QC2013C008）资助作者联系地址：1. 中国科学院上海高等研究院， 上海 201210； 2. 中国科学院大学， 北京 100049Author's Address: 1. Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China；2. University of Chinese Academy of Sciences, Beijing 100049, China通讯作者E-mail：[email protected]; [email protected]

Core-shell Pd@Pt Ultrathin Nanowires as Durable Oxygen Reduction Electrocatalysts

本文控制合成一维方向生长的直径为1.5 nm，长度为11.8 nm的超细Pd纳米线，结合欠电位沉积方法在其表面制备了不同Pt原子层的Pd@Pt核壳结构纳米电催化剂. 高分辨透射电镜和光电子能谱结果证实了这种核壳结构及Pt在Pd纳米线上的均匀分布. 相比于商业化Pt黑催化剂，该核壳结构电催化剂对酸性介质中的氧气还原反应呈现了较高的电催化活性和增强的耐久性. 显著增强的耐久性可归属于催化剂一维结构的稳定性.This paper describes a simple CO-assisted reduction approach for the controllable synthesis of ultrathin Pd nanowires along the one-dimensional (1D) direction. Ultrathin Pt films from one to several atomic layers were successfully decorated onto ultrathin Pd nanowires by utilizing Cu UPD deposition, and followed by in-situ redox replacement reaction of UPD Cu by Pt. The core–shell structure and composition of the Pd@Pt ultrathin nanowires have been verified using transmission electron microscopy and energy dispersive X-ray spectrometry. The core–shell Pd@Pt ultrathin nanowires exhibited comparative electrocatalytic activity and improved durability for the oxygen reduction reaction in comparison with commercial Pt black. The enhanced durability of the core-shell Pd@Pt catalyst could be ascribed to 1D structural stability.国家重点研发计划课题（No. 2016YFB010201）、国家自然科学基金项目（No. 21503262，No. 21533005） 资助作者联系地址：1.中国科学院上海高等研究院，上海201210；2. 中国科学院大学，北京100049；3. 上海科技大学，上海 201210Author's Address: 1.Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China；2. University of Chinese Academy of Sciences, Beijing 100039, China；3. ShanghaiTech University, Shanghai 201210, China通讯作者E-mail：[email protected]; [email protected]

Facile Preparation of Core–Shell Magnetic Metal–Organic Framework Nanospheres for the Selective Enrichment of Endogenous Peptides

Facile Preparation of Core–Shell Magnetic Metal–Organic Framework Nanospheres for the Selective Enrichment of Endogenous Peptide

Complex Reduction Preparation of Carbon Supported Pd Nanoparticle Catalyst and its Electrocatalysis for Formic Acid Oxidation

应用柠檬酸钠络合还原法制备了粒径小、分布均匀的碳载Pd纳米粒子(Pd/C).由于柠檬酸钠的络合作用,有效地降低了Pd粒子在形成过程中的团聚.经过简单的热处理调控Pd粒子大小,发现随热处理温度的升高,Pd粒子直径由初始的2.7 nm增大到5.8 nm左右.电化学测试表明Pd/C的Pd粒子尺寸越小,电催化甲酸氧化的质量比活性越高,但如当Pd粒径较大,则催化剂呈现出更高的面积比活性.Pd粒径为3.6 nm的催化剂,其电催化甲酸氧化的稳定性最好.A simple procedure involved the complexing of PdCl2 with sodium citrate followed by ethylene glycol reduction has been employed for the preparation of carbon-supported Pd nanoparticles(Pd/C).The XRD and TEM characterizations indicate that Pd nanoparticles with a small particle size were well-dispersed on carbon support.The mean particle sizes of the Pd/C catalysts were found to be increased from 2.7 to 5.8 nm with heat-treatments at different temperature.The mass activity of the Pd/C catalyst for formic acid electrooxidation increased with the decrease in Pd particle size.However,the specific activity increased with Pd particle size.Furthermore,the Pd/C catalyst with a particle size of ca.3.6 nm exhibited the best stability.作者联系地址：南京航空航天大学材料科学与技术学院;中国科学院上海微系统与信息技术研究所;Author's Address: 1.College of Materials Science and Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;2.Energy Science and Technology Laboratory,Shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences,Shanghai 200050,Chin