Hengyang Normal University

About: Hengyang Normal University is a education organization based out in Hengyang, China. It is known for research contribution in the topics: Graphene & Adsorption. The organization has 1087 authors who have published 1280 publications receiving 13850 citations. The organization is also known as: Hengyang Teachers' College & Héngyáng Shīfàn Xuéyuàn.

One-pot in situ synthesis of a CoFe2O4 nanoparticle-reduced graphene oxide nanocomposite with high performance for levodopa sensing

Abstract: In this work, a simple and facile protocol for the synthesis of a cobalt-ferrite magnetic nanoparticle-reduced graphene oxide nanocomposite (CoFe2O4/RGO) was achieved using an in situ chemical co-precipitation method. The characteristics of the synthesized nanocomposite were carefully investigated by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy and electrochemical technologies, respectively. The results reveal that the abundant CoFe2O4 nanoparticles are successfully formed with particle sizes in the range of 460–510 nm and uniformly anchored on the RGO nanosheets. Due to the imbedding of CoFe2O4 nanoparticles, the nanocomposite exhibits a larger surface area and superior electrocatalytic activity towards the oxidation of levodopa, which could be used as an efficient electrocatalyst for levodopa sensing. The parameters that influence the sensing property were investigated in detailed. Under the optimum conditions, the oxidation peak currents obtained by differential pulse voltammetry and chronoamperometry show linear responses for levodopa concentrations in the ranges of 0.02–45 μM and 10–420 μM respectively, and a low detection limit of 12 nM is achieved. Compared with those of the existing analogues reported for levodopa detection, the CoFe2O4/RGO-based sensor demonstrates outstanding properties such as high sensitivity, low detection limit and wide linear dynamic range. Finally, the practical analytical application of the developed sensor was assessed by the determination of levodopa in commercially available tablets and urine samples, and satisfactory recoveries were obtained in the range of 97.8–103.2%.

Tunable band gap and magnetism of the two-dimensional nickel hydroxide

Abstract: The electronic structures and magnetic properties of two dimensional (2D) hexagonal Ni(OH)2 are explored based on first-principles calculations. The results reveal that the ground state of the pristine Ni(OH)2 is a direct semiconductor with antiferromagnetic (AFM) coupling between two nearest Ni atoms. Interestingly, the monolayer Ni(OH)2 becomes a ferromagnetic (FM) semiconductor under a biaxial compressive strain of 4%. Furthermore, the band gap of monolayer Ni(OH)2 can be modulated by the different biaxial strains. These tunable electronic structures and magnetic properties of the Ni(OH)2 monolayer make it a promising candidate for applications in 2D spin-devices.

Molecularly imprinted polymer based on multiwalled carbon nanotubes for ribavirin recognition

Abstract: Molecularly imprinted polymers on the surface of multiwalled carbon nanotubes (MWNTs) have been developed for selective recognition for Ribavirin. The composites (MWNTs/MIPs) were prepared by using Ribavirin as the template molecule, acrylamide (AAM) as the functional monomer, N, N-methylenebisacrylamide (NNMBA) as the cross-linker. MWNTs/MIPs obtained were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The properties such as adsorption dynamics, special binding, and the selective recognition ability were evaluated. The adsorption equilibrium was arrived in about 4 h which indicated that the adsorption kinetic was comparatively fast. The results of binding and selectivity experiments showed that the MWNTs/MIPs could bind the template molecule selectively in aqueous media.