3 research outputs found
Ultrathin Au-Alloy Nanowires at the Liquid–Liquid Interface
Ultrathin
bimetallic nanowires are of importance and interest for
applications in electronic devices such as sensors and heterogeneous
catalysts. In this work, we have designed a new, highly reproducible
and generalized wet chemical method to synthesize uniform and monodispersed
Au-based alloy (AuCu, AuPd, and AuPt) nanowires with tunable composition
using microwave-assisted reduction at the liquid–liquid interface.
These ultrathin alloy nanowires are below 4 nm in diameter and about
2 μm long. Detailed microstructural characterization shows that
the wires have an face centred cubic (FCC) crystal structure, and
they have low-energy twin-boundary and stacking-fault defects along
the growth direction. The wires exhibit remarkable thermal and mechanical
stability that is critical for important applications. The alloy wires
exhibit excellent electrocatalytic activity for methanol oxidation
in an alkaline medium
Correction to Ultrathin Au-Alloy Nanowires at the Liquid–Liquid Interface
Correction to Ultrathin Au-Alloy Nanowires at the
Liquid–Liquid Interfac
Screening Precursor–Solvent Combinations for Li<sub>4</sub>Ti<sub>5</sub>O<sub>12</sub> Energy Storage Material Using Flame Spray Pyrolysis
The development and
industrial application of advanced lithium based energy-storage materials
are directly related to the innovative production techniques and the
usage of inexpensive precursor materials. Flame spray pyrolysis (FSP)
is a promising technique that overcomes the challenges in the production
processes such as scalability, process control, material versatility,
and cost. In the present study, phase pure anode material Li<sub>4</sub>Ti<sub>5</sub>O<sub>12</sub> (LTO) was designed using FSP via extensive
systematic screening of lithium and titanium precursors dissolved
in five different organic solvents. The effect of precursor and solvent
parameters such as chemical reactivity, boiling point, and combustion
enthalpy on the particle formation either via gas-to-particle (evaporation/nucleation/growth)
or via droplet-to-particle (precipitation/incomplete evaporation)
is discussed. The presence of carboxylic acid in the precursor solution
resulted in pure (>95 mass %) and homogeneous LTO nanoparticles
of size 4–9 nm, attributed to two reasons: (1) stabilization
of water sensitive metal alkoxides precursor and (2) formation of
volatile carboxylates from lithium nitrate evidenced by attenuated
total reflection Fourier transform infrared spectroscopy and single
droplet combustion experiments. In contrast, the absence of carboxylic
acids resulted in larger inhomogeneous crystalline titanium dioxide
(TiO<sub>2</sub>) particles with significant reduction of LTO content
as low as ∼34 mass %. In-depth particle characterization was
performed using X-ray diffraction with Rietveld refinement, thermogravimetric
analysis coupled with differential scanning calorimetry and mass spectrometry,
gas adsorption, and vibrational spectroscopy. High-resolution transmission
electron microscopy of the LTO product revealed excellent quality
of the particles obtained at high temperature. In addition, high rate
capability and efficient charge reversibility of LTO nanoparticles
demonstrate the vast potential of inexpensive gas-phase synthesis
for energy-storage materials