Controllable Synthesis of Ultrathin NiCo₂O₄ Nanosheets Incorporated onto Composite Nanotubes for Efficient Oxygen Reduction

Abstract

Exploring non-precious-metal-based oxygen reduction reaction (ORR) electrocatalysts featuring high efficiency, low cost, and environmental friendliness is of great importance for the broad applications of fuel cells and metal-air batteries. In this work, ultrathin NiCo O nanosheets deposited on 1D SnO nanotubes (SNT) were successfully fabricated through a productive electrospinning technique followed by a sintering and low-temperature coprecipitation strategy. This hierarchically engineered architecture has ultrathin NiCo O nanosheets uniformly and fully erected on both walls of tubular SNTs, which results in improved electrochemical activity as an ORR catalyst, in terms of positive onset potential and high current density, as well as superior tolerance to crossover effects and long-term durability with respect to the commercial Pt/C catalyst. The excellent performance of SNT@NiCo O composites may originate from their rationally designed hierarchical tubular nanostructure with completely exposed active sites and interconnected 1D networks for efficient electron and electrolyte transfer; this makes these composite nanotubes promising candidates to replace platinum-based catalysts for practical fuel cell and metal-air battery applications.

Electrospun Carbon Nanofibers Encapsulated with NiCoP: A Multifunctional Electrode for Supercapattery and Oxygen Reduction, Oxygen Evolution, and Hydrogen Evolution Reactions

“…Therefore, www.advenergymat.de www.advancedsciencenews.com the electrochemical water-splitting systems are very much betrothed in generating renewable and clean energy resources to replace the use of fossil fuels. [25] Likewise, Shang et al have synthesized MnO and N-doped carbon nanofibers through electrospinning and pyrolysis. [14,22,23] These ORR, OER, and HER are highly dependent on their catalysts that create operational efficiencies.…”

Flower-like NiCo2O4–CN as efficient bifunctional electrocatalyst for Zn-Air battery

“…Through morphology controlling, NiCo 2 O 4 with larger surface area, porous and 3D hierarchical structure could be fabricated, which could provide more accessible active sites for ORR/OER. Some successful examples are nanowire [7], nano platelet [8], nanosphere [9,10], and 3D nanoshees [11,12]; (2) Metal doping. The electronic structure of spinel oxides is highly related to its composition, and the composition adjustment by a third metal doping is an effective strategy to improve the activity.…”

Metal‐Nitrogen‐doped Porous Carbons Derived from Metal‐Containing Ionic Liquids for Oxygen Reduction Reaction

“…In Figure8f, the lattice spacingo f 0.21 nm is observed, representing the presence of metallic Cu, which is further indicated by the XRD pattern of MIBA-Cu-1000 in Figure S6 b. [50,51] Co 3 Cw ithl attice spacing of 0.21 nm is found in MIBA-Co-1000( Figure8h) and is furthers uppoeted by the XRD pattern of MIBA-Co-1000 in Figure S6 c. [52,53] Meanwhile,t he presence of Cu and Co 3 Cc an only been seen in the big particles attached to carbons (Figure 8e,g). However,i n MIBA-Fe-900, the lattice spacing of 0.22 nm indicates Fe 3 Ci s furthers upported by the XRD pattern of MIBA-Fe-900 in Figure S6 aa nd is observed not only in the biggerp articles (Figure 8b)b ut also in small particles embedded in carbon (Figure 8d).…”

“…The oxygen reduction reaction( ORR) is ac ornerstoneo fm any promising, green and efficient energy-conversion devices,e specially fuel cells. [1][2][3] Low-temperature fuel cells usually exhibit weaker output performance in practice, instead of the high ideal thermodynamic efficiency,d ue to enormousa ctivation energy barriers and sluggish kineticso fO RR at the cathode. [4,5] Amongv arious materials explored, the noble-metalp latinum (Pt) based catalysts have been shown to be the most efficient catalysts to boost ORRi np ractical applications.…”

“…HNMR (400 MHz, D 2 O): d = 8.72-8.62 (d, 1H), 7.31-7.48 (d, 2H), 4.96 (s, 2H), 3.89 (s, 3H). Ba(OH) 2 ·8 H 2 O (3.56 g, 11.31 mmol) was added into the aqueous solution containing MIBA (5.00 g, 22.62 mmol) and 20 mL deionized water.A fter the reaction for 12 h, equivalent CuSO 4 ,C oSO 4 ·7 H 2 Oo rF e 2 (SO 4 )3 was added. After the further reaction for 3h,t he mixture was centrifuged to give ac lear solution.…”