Improvement of energy conversion efficiency and power generation in direct borohydride-hydrogen peroxide fuel cell: The effect of Ni-M core-shell nanoparticles (M = Pt, Pd, Ru)/Multiwalled Carbon Nanotubes on the cell performance

Template‐free synthesis of novel hollow carbon nanospheres with dual active sites as catalyst for fuel cell cathode to improve oxygen reduction reaction performances

“…Remarkably, the weight loss is only 1.3% in the temperature range from 580°C to 800°C, which shows that the hollow shell structure has completely formed at 580°C and also reveals that this hollow shell structure is very stable. 19,25 Especially, pyridinic N and graphitic N can form larger π-π structure conjugate bond with carbon sp 2 structure, reducing the apparent activation energy and further speeding up the kinetic reaction. When the temperature exceeds 800°C, the HCN-FNFCG continues to degrade slowly.…”

“…Fourth, high content of nitrogen element is favorable for ORR. 19,25 Especially, pyridinic N and graphitic N can form larger π-π structure conjugate bond with carbon sp 2 structure, reducing the apparent activation energy and further speeding up the kinetic reaction. And last but not least, thermal degradation temperature plays a very important role for the formation of ORR active sites for FeC 3 and FeN 4 .…”

“…18 It may be that in high-temperature process, the nitrogen of the aromatic chain is more likely to form pyridinic nitrogen and graphitic nitrogen under the catalysis of transition metals (eg, Fe, Co, Ni, Mn, and Zn), which two types of nitrogen sources are considered as the ORR active sites. 21,22 Besides, in order to improve ORR catalytic activity and to maximize numbers of the ORR active sites, hollow nanostructure engineering and hierarchical porosity system has been performed, including nanotubes, [24][25][26] nitrogen-doped carbon hollow nanospheres, 27,28 and nanocage. Besides, a simple and practical method of large-scale synthesis for Fe-N-C catalysts with good ORR properties still exist great challenge.…”

“…23 For example, FeN 4 active sites were fabricated by a silica-protected strategy, but it is commonly needed to remove silica-template. 21,22 Besides, in order to improve ORR catalytic activity and to maximize numbers of the ORR active sites, hollow nanostructure engineering and hierarchical porosity system has been performed, including nanotubes, [24][25][26] nitrogen-doped carbon hollow nanospheres, 27,28 and nanocage. 29 Moreover, a variety of templates, such as Ni foam, 30 SBA-15, 31 metal organic frameworks (MOFs), 32,33 silicon dioxide, 34 or the complicated self-assembly processes, have been applied to prepare hollow and porous metal-Nx-Cy nanomaterials.…”

A Pt/MnV2O6 nanocomposite for the borohydride oxidation reaction

“…Direct borohydride fuel cell (DBFC) has emerged as a new technology in a wide search for safe and clean power sources for portable applications and electrical vehicles [1][2][3]. This power source is environmentally friendly and thus presents an excellent replacement for today's polluting fossil fuel-based technologies.…”