Electrochemical conversion of CO into energy-dense liquids, such as formic acid, is desirable as a hydrogen carrier and a chemical feedstock. SnO is one of the few catalysts that reduce CO into formic acid with high selectivity but at high overpotential and low current density. We show that an electrochemically reduced SnO porous nanowire catalyst (Sn-pNWs) with a high density of grain boundaries (GBs) exhibits an energy conversion efficiency of CO -into-HCOOH higher than analogous catalysts. HCOOH formation begins at lower overpotential (350 mV) and reaches a steady Faradaic efficiency of ca. 80 % at only -0.8 V vs. RHE. A comparison with commercial SnO nanoparticles confirms that the improved CO reduction performance of Sn-pNWs is due to the density of GBs within the porous structure, which introduce new catalytically active sites. Produced with a scalable plasma synthesis technology, the catalysts have potential for application in the CO conversion industry.

In this paper, the LiSiO nanowires (NWs) were shown to be promising for CO capture with ultrafast kinetics. Specifically, the nanowire powders exhibited an uptake of 0.35 g g of CO at an ultrafast adsorption rate of 0.22 g g min at 650-700 °C. Lithium silicate (LiSiO) nanowires and nanopowders were synthesized using a "solvo-plasma" technique involving plasma oxidation of silicon precursors mixed with lithium hydroxide. The kinetic parameter values (k) extracted from sorption kinetics obtained using NW powders are 1 order of magnitude higher than those previously reported for the LiSiO-CO reaction system. The time scales for CO sorption using nanowires are approximately 3 min and two orders magnitude faster compared to those obtained using lithium silicate powders with spherical morphologies and aggregates. Furthermore, LiSiO nanowire powders showed reversibility through sorption-desorption cycles indicating their suitability for CO capture applications. All of the morphologies of LiSiO powders exhibited a double exponential behavior in the adsorption kinetics indicating two distinct time constants for kinetic and the mass transfer limited regimes.

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In order to make fast-charging batteries a reality for electric vehicles, durable, more energy dense and high-current density resistant anodes need to be developed. With such purpose, a low lithiation potential of 0.2 V vs. Li/Li+ for MoO3 nanoplatelet arrays is reported here for anodes in a lithium ion battery. The composite material here presented affords elevated charge capacity while at the same time withstands rapid cycling for longer periods of time. Li2MoO4 and Li1.333Mo0.666O2 were identified as the products of lithiation of pristine MoO3 nanoplatelets and silicon-decorated MoO3, respectively, accounting for lower than previously reported lithiation potentials. MoO3 nanoplatelet arrays were deposited using hot-wire chemical vapor deposition. Due to excellent voltage compatibility, composite lithium ion battery anodes comprising molybdenum oxide nanoplatelets decorated with silicon nanoparticles (0.3% by wt.) were prepared using an ultrasonic spray. Silicon decorated MoO3 nanoplatelets exhibited enhanced capacity of 1037 mAh g−1 with exceptional cyclablity when charged/discharged at high current densities of 10 A g−1.

This paper reports a fast, scalable method for synthesizing tin oxide nanowire powder using cheap starting material of commercial tin oxide particles and an atmospheric microwave plasma reactor. Specifically, the synthesis concept involves plasma oxidation of tin oxide powder combined with potassium hydroxide for few seconds to a minute which is orders of magnitude lower than that using hydrothermal or vapor-liquid-solid (VLS) techniques. Even at lab scale, large-scale production of tin oxide nanowire powder as high as 10 grams per hour has been produced. Systematic studies reveal nucleation and growth of K 2 SnO 3 nanowires from molten alloy involving KOH and tin oxide. A simple annealing step is used to convert K 2 SnO 3 intermediate nanowires into pure tin oxide nanowires. The extremely short reaction time of 20 seconds is three orders of magnitude faster than that of traditional hydrothermal method. It was shown that our tin oxide nanowire powder shows a high reversible capacity of 848 mAh g -1 after 55 cycles at a current density of 100 mA g -1 . The scalable production technique presented here and the applicability of resulting tin oxide nanowire powders makes it as suitable for practical implementation into lithium-ion battery applications. ASSOCIATED CONTENTSupporting Information: Raman spectrum of porous tin oxide nanowires, In-situ measurement of sample surface temperature, Thermodynamic data and growth rate calculations. AUTHOR INFORMATION