Qinfang Zhang

One-step in situ synthesis of ultrathin tungsten oxide@carbon nanowire webs as an anode material for high performance

A novel ultrathin W18O49@carbon nanowire web anode material for high performance lithium-ion batteries is synthesized via a facile one-step solvothermal method. A carbon layer is uniformly coated on ultrathin W18O49 nanowire bundles. The electrochemical properties are analyzed by cyclic voltammetry, galvanostatic charge/discharge cycling and electrochemical impedance. The W18O49@carbon nanowire web electrode exhibits a high lithium storage capacity of 889 mA h g−1 after 250 cycles at 200 mA g−1, which is the best cycling performance among the tungsten oxide anode materials used in lithium-ion batteries reported to date. The improved electrochemical performance can be ascribed to the incorporation of carbon and the unique ultrathin nanowire web architecture of the nanocomposite.

Layer-by-layer assembly modification to prepare firmly bonded Si–graphene composites for high-performance anodes

A new nanocomposite of Si nanoparticles homogenously encapsulated in a graphene composite was prepared by a facile layer-by-layer (LBL) assembled modification method, followed by an electrostatic attraction directed self-assembly approach and thermally reduced process. The wrinkled graphene sheets were assembled into a three-dimensional network and covered the surface of the highly dispersed Si nanoparticles well. The as-prepared Si–graphene composite exhibited good electrochemical performance as an anode material in lithium-ion batteries, showing a stable reversible capacity of 1150 mA h g−1 with a high capacity retention rate of 92.0% over 100 cycles and high rate capability (840 mA h g−1 at 3000 mA g−1).

Novel CO2 Fluorescence Turn-On Quantification Based on a Dynamic AIE-Active Metal–Organic Framework

Traditional CO2 sensing technologies suffer from the disadvantages of being bulky and cross-sensitive to interferences such as CO and H2O, these issues could be properly tackled by innovating a novel fluorescence-based sensing technology. Metal-organic frameworks (MOFs), which have been widely explored as versatile fluorescence sensors, are still at a standstill for aggregation-induced emission (AIE), and no example of MOFs showing a dynamic AIE activity has been reported yet. Herein, we report a novel MOF, which successfully converts the aggregation-caused quenching of the autologous ligand molecule to be AIE-active upon framework construction and exhibits bright fluorescence in a highly viscous environment, resulting in the first example of MOFs exhibiting a real dynamic AIE activity. Furthermore, a linear CO2 fluorescence quantification for mixed gases in the concentration range of 2.5-100% was thus well-established. These results herald the understanding and advent of a new generation in all solid-state fluorescence fields.

The usage of rankinite for carbon capture and storage and carbonation kinetics

ABSTRACT Low-calcium rankinite C3S2 (3CaO•2SiO2) cement is an a dvanced low-calcium and saving energy cement which hardens by carbonation. The progress of rankinite carbonation and the mechanical strength of C3S2 carbonized block were studied. The effects of time, CO2 pressure, temperature, and relative humidity (RH) during carbonation-curing on C3S2 powder were also investigated. We especially focus on the establishment of kinetic equation of carbonation-curing of C3S2 powder. The results show that the main product of C3S2 carbonization is CaCO3. As a result, 1 kg of C3S2 could capture 0.15 kg CO2 after 12 h of carbonation-curing, and the compressive strength was 10.2 and 21.3 MPa after carbonation for 3 and 12 h, respectively. The developed kinetic model was able to predict the relationship of carbonation degree and time, temperature, CO2 pressure, and RH under the tested carbonation conditions.

Study on structural characteristics and adsorption performance of ultrasonic treated Mn-containing sulfur transfer agent

Abstract To prepare manganese-containing spinel sulfur transfer agent with acid peptization, ultrasonic wave is used for the first time to modify the structure of sulfur transfer agent in this work. Mini fixed bed reactor was used to investigate the effect of ultrasonic power, time and temperature on the structure and oxidation adsorption performance of sulfur transfer agent and the adsorption kinetics and mechanism of SO2 were analyzed. SEM, TEM, XRD and N2 adsorption-desorption techniques were employed to characterize and analyse the function of sulfur transfer agent. The results indicated that manganese-containing spinel is a kind of promising sulfur transfer agent and exhibits higher sulfur capacity and desulfurization degree under the selected conditions of the ultrasonic wave power of 60%, and with the treatment period for 3 h at a temperature of 60 °C.