Ming-Fu Ye

Advanced electrochemical properties of Mo-doped Li4Ti5O12 anode material for power lithium ion battery

Mo6+-doped Li4Ti5−xMoxO12 (0 ≤ x ≤ 0.2) samples have been synthesized via a simple solid-state reaction. The products were characterized by X-ray diffraction (XRD), Raman spectroscopy (RS), scanning electronic microscope (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge testing. Li4Ti5−xMoxO12 (x = 0, 0.05) shows the pure phase structure, but several impurity peak can be detected when x ≥ 0.1. Mo-doping did not change the electrochemical reaction process and basic spinel structure of Li4Ti5O12. The particle size of the Li4Ti5−xMoxO12 (0≤ x ≤ 0.2) sample was about 2–3 μm and Li4Ti5O12 has less agglomeration. Electrochemical results show that the Mo6+-doped Li4Ti5O12 samples display a larger diffusion coefficient of lithium ions, lower charge transfer resistance, higher rate capability and excellent reversibility. The Li4Ti5−xMoxO12 (x = 0.1, 0.15) sample maintained considerable capacities until 6 C rates, whereas pristine Li4Ti5O12 shows a severe capacity decline at high rates. After 100 cycles, the specific reversible capacities of Li4Ti5O12 and Li4Ti4.9Mo0.1O12 are 195.8 and 210.8 mAh g−1, respectively. The superior cycling performance and wide discharge voltage range, as well as simple synthesis route and low synthesis cost of the Mo-doped Li4Ti5O12 are expected to show a potential commercial application.

Facile synthesis of amine-functionalized SBA-15-supported bimetallic Au–Pd nanoparticles as an efficient catalyst for hydrogen generation from formic acid

In this study, a series of amine-functionalized SBA-15-supported bimetallic Au–Pd nanoparticles (Au–Pd/SBA-15-Amine) as catalysts are successfully synthesized by surface functionalization and co-reduction and characterized by inductively coupled plasma-atomic emission spectroscopy, XRD, XPS, and TEM. The Au–Pd/SBA-15-Amine catalysts thus obtained are tested for the dehydrogenation of formic acid (FA)–sodium formate (SF). Among the tested Au–Pd/SBA-15-Amine catalysts, as-synthesized Au2Pd8/SBA-15-Amine exhibits 100% H2 selectivity and outstanding catalytic activity with an initial turnover frequency (TOF) of 1786 h−1 at 323 K; this superior catalytic activity is attributed to synergy between Au–Pd and SBA-15-Amine and the promotion effect of SF. At SF concentrations of greater than 0.5 mol L−1, SF can partially participate in dehydrogenation. The facile synthesis of the Au–Pd/SBA-15-Amine catalyst is imperative for accelerating the widespread application of FA–SF mixtures as a promising hydrogen carrier.