Jiali Sheng,Jiahui Kang,Zhixiong Hu,Yan Yu,Xian-Zhu Fu,Rong Sun,Ching-Ping Wong
Exploring effective electrocatalysts is in urgent demand to boost their large-scale applications for direct ethanol fuel cells. Herein, for the first time, we report nanoparticle-assembled Pd nanocages with efficient catalytic activity towards ethanol electrochemical oxidation. The catalysts are prepared from the second template of a nanosheet surface of amorphous Co(OH)2 octahedral nanocages, which are prepared from the original template of octahedral Cu2O. These Pd octahedral nanocages exhibit a porous rough surface, which consists of smaller Pd nanoparticles, endowing them with highly active surface area and many active sites. For the electrochemical oxidation of ethanol, the Pd nanocages demonstrate superior activity (3765 mA mgPd−1), 4.8 times and 5.9 times those of commercial Pd/C and Pd nanocatalysts, respectively, prepared directly from an octahedral Cu2O original template. Furthermore, the Pd nanocages demonstrate excellent long-term durability.
Xingchi Li,Huaming You,Cheng Wang,Dongmei Liu,Rui Yu,Siyu Guo,Yuan Wang,Yukou Du
Modifying the electronic structure and optimizing the geometric structure can expeditiously tune the electrocatalytic properties of catalysts, resulting in considerably enhanced electrocatalytic performance towards electrocatalytic oxidation of liquid fuels . We herein report a simple synthetic strategy to prepare Bi-doped 3D taraxacum-like Pd nanocages (NCs) composed of porous nanosheets , which possess high surface areas and strong synergistic effects. Notably, a trace of Bi diffuses into the lattice of Pd and increases the electronic effects of the surface of Pd, endowing PdBi-0.5 NCs/C with superior electrocatalytic performance towards ethanol oxidation reaction (EOR). The mass activity and specific activity of PdBi-0.5 NCs/C were 3494.8 mA mg Pd −1 and 10.37 mA cm −2 , being 4.08- and 4.82- fold enhancements as compared with commercial Pd/C, respectively. Moreover, the highly open porous 3D nanocages structure with rich active sites and defects can also facilitate the mass/electron transfer to favor the EOR kinetics.
Shuli Yin,You Xu,Songliang Liu,Hongjie Yu,Ziqiang Wang,Xiaonian Li,Liang Wang,Hongjing Wang
The development of doped noble metal catalysts with nonmetal elements to improve the catalytic performance toward the oxygen reduction reaction (ORR) is significant for proton exchange membrane fuel cell technology. Here, we report a one-pot for dual-nonmetal-doping strategy for the synthesis of S and P-co-doped mesoporous PtPd nanocages (PtPdSP mNCs) by using pre-synthesized mesoporous PtPd nanocages (PtPd mNCs) as the precursor and triphenylphosphine sulphide as both S and P sources. Benefitting from the combined advantages of metal–nonmetal incorporation, hollow cavity and surface porosity, the resultant quaternary PtPdSP mNCs exhibit outstanding ORR activity and long-term stability. This research work provides a good strategy for the doping of two or more selected nonmetallic elements into metallic nanocrystals with a controllable structure and composition.