Antimony Oxides-Based Anode Materials for Alkali Metal-Ion Storage.

With the increasing demand for renewable energy, alkali metal-ion (lithium/sodium/potassium-ion) batteries play more and more important roles in the field of static storage and electrical vehicle industry. Novel anode materials with high reversible capacity, safety and long-term cycling stability are desiderated to meet the ever-growing demand for alkali metal-ion batteries with high electrochemical performance. Antimony oxides (Sbx Oy ) show electrochemical reaction activity with all of lithium, sodium and potassium, and are expected to be promising anode materials for alkali metal-ion storage due to their high theoretical capacities, appropriate operating potential and excellent safety properties. This review is devoted to overview the research progress on reaction mechanism and improvements in electrochemical performance of antimony oxides for alkali metal-ion storage, and look forward to their further prospects.

Improvement of the activity and SO2 tolerance of Sb-modified Mn/PG catalysts for NH3-SCR at a low temperature.

A series of MnM/palygorskite (PG) (M = La, W, Mo, Sb, Mg) catalysts was prepared by the wetness co-impregnation method for low-temperature selective catalytic reduction (SCR) of NO with NH3. Conversion efficiency followed the order Sb > Mo > La > W > Mg. A combination of various physico-chemical techniques was used to investigate the influence of Sb-modified Mn/PG catalysts. MnSb0.156/PG catalyst showed highest NO conversion at low temperatures in the presence of SO2 which reveals that addition of Sb oxides effectively enhances the SCR activity of catalysts. A SO2 step-wise study showed that MnSb0.156/PG catalyst displays higher durable resistance to SO2 than Mn/PG catalyst, where the sulfating of active phase is greatly inhibited after Sb doping. Scanning electron microscopy and X-ray diffraction results showed that Sb loading enhances the dispersion of Mn oxides on the carrier surface. According to the results of characterization analyses, it is suggested that the main reason for the deactivation of Mn/PG is the formation of manganese sulfates which cause the permanent deactivation of Mn-based catalysts. For Sb-doped Mn/PG catalyst, SOx ad-species formed were mainly combined with SbOx rather than MnOx. This preferential interaction between SbOx and SO2 effectively shields the MnOx as active species from being sulfated by SO2 resulting in the improvement of SO2 tolerance on Sb-added catalyst. Multiple information support that, owing to the addition of Sb, original formed MnOx crystallite has been completely transformed into highly dispersed amorphous phase accounting for higher SCR activity.

Immobilizing arsenic-enriched wastewater from utilization of crude antimony oxides as scorodite using a novel multivalent iron source.

Arsenic-enriched wastewater (A-EW) is a hypertoxic sewage from the utilization of crude antimony oxides in lead anode slime metallurgy. In traditional methods, the H+ accumulation inhibits the arsenic immobilization during scorodite synthesis. In this study, a novel multivalent iron source comprised of Fe(OH)3 and FeSO4·7H2O was proposed to resolve the adverse effects of pH fluctuation during immobilizing A-EW as scorodite. Various approaches, such as scanning electron microscopy and X-ray photoelectron spectroscopy, were applied to characterize the synthesized scorodite. This work was divided into two parts. In thermodynamics, HnAsO4(3-n)- (n = 1, 2, 3) and Fe(OH)n(3-n)+ (n = 0, 1, 2, 3) can feasibly coprecipitate as scorodite according to their △rGm,Tθ ranged from -111.10 kJ mol-1 to -33.53 kJ mol-1. In experimental research, A-EW was immobilized as scorodite by optimizing conditions as initial pH = 2.0, molar ratio of Fe to As = 1.2, molar ratio of Fe(II) to Fe(III) = 4:6, arsenic concentration = 40 g/L, and temperature = 95 °C. The arsenic precipitation ratio is 99.60%, and the micromorphology of synthesized scorodite presents a regular octahedron having size of 5-10 µm. The low leachability of As (0.41 mg/L) in toxicity characteristic leaching procedure (TCLP) confirmed that the prepared scorodite is nonhazardous. The solution pH is stable at 2.0 as the H+ depletion (0.5660 mol) by Fe(OH)3 dissolution and Fe2+ oxidization balanced with that (0.5657 mol) generated from As(V)-Fe(III) coprecipitation. In general, the A-EW was effectively immobilized by proposed multivalent iron source, and can be potentially applied to safely dispose other industrial effluents, such as high arsenic leachates and arsenic-bearing waste acid from nonferrous metallurgy.

Synthesis of merit-combined antimony tetroxide nanoflowers/reduced graphene oxide to synergistically boost real-time detection of nitric oxide released from living cells for high sensitivity.

Nitric oxide (NO) is an important bio-regulatory and signaling molecule associated with various physiological and pathophysiological pathways, but its sensitive real-time detection is still very challenging due to the low concentration, large diffusivity and fast decay in biological samples. Here an antimony tetroxide (Sb2O4) nanoflowers/reduced graphene oxide (rGO) nanocomposite is synthesized via a facile and eco-friendly solvothermal method to merit-combine highly electroactive Sb2O4 nanoflowers with large surficial rGO component for a strong synergistic effect on oxidation of NO. Results demonstrate that the Sb2O4/rGO-based sensor has a low detection limit, high sensitivity, excellent selectivity and fast response for NO detection. The real-time detected NO released from living cells showed significant difference between normal and tumor cells. The Sb2O4 nanoflowers/rGO nanocomposite sensor holds a great promise for important applications in biomedical research fields and clinical diagnosis.

Electrocatalysis of Lindane Using Antimony Oxide Nanoparticles Based-SWCNT/PANI Nanocomposites.

This work describes the chemical synthesis of antimony oxide nanoparticles (AONPs), polyaniline (PANI), acid functionalized single-walled carbon nanotubes (fSWCNTs), and the nanocomposite (AONP-PANI-SWCNT) as catalyst for the trace detection of lindane. Successful synthesis of the nanomaterials was confirmed by Fourier transform infrared (FT-IR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, x-ray diffraction (XRD) spectroscopy, and scanning electron microscopy (SEM). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used for investigating the electrochemical behavior of the modified electrodes in the ferrocyanide/ferricyanide ([Fe(CN)6]4-/[Fe(CN)6]3-) redox probe. GCE-AONP-PANI-SWCNT exhibited faster electron transport properties as well as higher electroactivity as compared to bare-GCE, GCE-AONPs, GCE-PANI, and GCE-SWCNT electrodes. Electrocatalytic studies further showed that GCE-AONP-PANI-SWCNT modified electrode was stable (after 20 scans) with only a small current drop in lindane (0.57%). The GCE-AONP-PANI-SWCNT electrode with low detection limit of 2.01 nM performed better toward the detection of lindane as compared to other studies in literature. The GCE-AONP-PANI-SWCNT electrode is highly selective toward the detection of lindane in the presence of various organic and inorganic interfering species. Real sample analysis of river water and tap water samples using the developed sensor gave satisfactory percentage recoveries therefore confirming the potential of the proposed sensor for practical application.