Fabrication of high sensitivity 2-PEA sensor based on Aldehyde-functionalized mesoporous carbon

2-Phenylethylamine(2-PEA)is one of the main ingredients for stimulants.Therefore,it is necessary to limit its use and illegal trade by conveniently detecting 2-PEA vapour.Here,a QCM based 2-PEA gas sensor was constructed by using aldehyde functionalized mesoporous carbon(FDU-15-CHO)as sensing materials designed according to Schiff base adsorption role.The 2D hexagonal mesoporous structures of the sensing material have been confirmed by small-angle X-ray diffraction(SXRD),transmission electron microscopy(TEM),and N2adsorption-desorption isotherms.The covalent grafting of aldehyde group onto the FDU-15 was confirmed by Fourier transform infrared spectroscopy(FT-IR).FDU-15-CHO based Quartz Crystal Microbalance(QCM)sensor shows better sensitivity to 2-PEA than its parent FDU-15.Besides,the detection limit of FDU-15-CHO based sensor can reach down to 1 ppm,and its selectivity and reproducibility are satisfactory.The high concentrations of active sites in the mesopores of FDU-15 are believed to facilitate 2-PEA adsorption,and thus the presence of the-CHO group leading to sensitive and selective response,which is verified by Gaussian simulation.

Preparation of functional ordered mesoporous carbons and their application as the QCM sensor with ultra-low humidity

Ordered mesoporous carbon(OMCs)FDU-15 was synthesized through an EISA(Evaporation-Induced Self-Assembly)method,and the oxidized OMCs(FDU-15-COOH)were obtained by subsequent oxidation treatments in liquid phase to introduce functional groups,The samples were characterized by XRD,TEM,FT-IR and nitrogen adsorption-desorption test,The low humidity sensing performances of FDU-15 and FDU-15-COOH thin films were investigated by using a quartz crystal microbalance(QCM)transducer.The responses of FDU-15-COOH is higher than that of the pristine FDU-15 at very low humidity(<729 ppmv)with high long-term stability,implying that FDU-15-COOH is a good candidate for low humidity QCM sensor.

Two-Layer High-Throughput:Effective Mass Calculations Including Warping

In this paper,we perform two-layer high-throughput calculations.In the first layer,which involves changing the crystal structure and/or chemical composition,we analyze selected Ⅲ-Ⅴ semiconductors,filled and unfilled skutterudites,as well as rock salt and layered chalcogenides.The second layer searches the full Brillouin zone(BZ)for critical points within 1.5 eV(1 eV=1.602176×10^(-19)J)of the Fermi level and characterizes those points by computing the effective masses.We introduce several methods to compute the effective masses from first principles and compare them to each other.Our approach also includes the calculation of the density-of-states effective masses for warped critical points,where traditional approaches fail to give consistent results due to an underlying non-analytic behavior of the critical point.We demonstrate the need to consider the band structure in its full complexity and the value of complementary approaches to compute the effective masses.We also provide computational evidence that warping occurs only in the presence of degeneracies.