Magnetic field assisted chemical reduction preparation of Co–B alloys as anode materials for alkaline secondary battery

Magnetic field-assisted solvothermal assembly of one-dimensional nanostructures of Ni–Co alloy nanoparticles

“…Magnetic-field-induced (MFI) assembly has been established as a powerful and versatile avenue to obtain one-dimensional (1D) structures. Despite these achievements, most of these researches were focused on morphology variation of aggregated elemental crystals and magnetic oxides from the point of view of assembly; the solution growth of binary alloys in the magnetic field is rarely reported [17,18]. Due to the difference of magnetic properties between two elements, the magnetic field is supposed to exert an effect on the microstructure and composition of the binary alloy during the synthesis process.…”

Mechanochemical synthesis and electrochemical characterization of VBx as high capacity anode materials for air batteries

“…2, all the samples showed welldefined anodic current bands, indicating electrochemical feasibility for anodic oxidation of these samples. However, the anodic current for electrochemical oxidation of all the VB x materials arose from much more positive potentials (−0.9 V to −0.5 V vs. Hg/HgO) than the equilibrium potential of boron (H 2 BO − 3 +H 2 O + 3e − B+4OH − , −1.79 V vs. standard hydrogen electrode (SHE) [9]) and vanadium (HV 6 O 3− 17 + 16H 2 O + 30e − 6V + 33OH − , 1.154 V vs. SHE [12]). These huge electrochemical polarizations could be accounted for by the fact that vanadium is fully in passive state at its equilibrium potential in the alkaline solution [13] and also elemental boron is electrochemically inert due to its very poor electronic conductivity (1 × 10 −6 -7 × 10 −8 S cm −1 [7]).…”

“…A most effective way to enhance the energy density of batteries is to utilize multi-electron redox compounds for electrode-active materials [1]. In this respect, superiron [2,3] and permanganate [4,5] demonstrated superiorly high capacities as cathodic materials and some transitional metal diborides [6][7][8][9] exhibited a capacity several times higher than conventional Zn anode. Particularly, among the metal borides reported, crystalline VB 2 showed the highest discharge capacity of >3300 mAh g −1 [8], which even exceeds the volumetric energy density of gasoline [8].…”

Effect of preparation temperature and ions doping on size, morphology and catalytic activity of Co-B amorphous nano catalyst

“…This particle agglomeration lowers the effective surface area of the catalyst powder thus limiting its catalytic activity. It is found that, chemical reduction reaction is most frequently used in preparing Co-B amorphous alloys [11][12][13][14][15]; however, the regular Co-B samples obtained via direct reduction of cobalt salt solution with a sodium borohydride solution usually display low surface area, broadly distributed particle size, and poor thermal stability against crystallization due to aggregation, because the reduction reaction is vigorous and exothermic [16,17]. Nitro compounds are widely generated as by-products in different industries like agrochemicals, coloring agents, and pharmaceutical products.…”