Yushu Tang

TiO2 decorated Co3O4 acicular nanotube arrays and its application as a non-enzymatic glucose sensor.

TiO2 modified Co3O4 acicular nanotube arrays (ANTAs) have been fabricated in this study, showing a good performance in glucose detection. In the experiment, the precursor Co(CO3)0.5(OH)·0.11H2O acicular nanowire arrays (ANWAs) was first grown on the fluorine doped tin oxide (FTO) substrate by a hydrothermal method. Thereafter, the uniform pink precursor Co(CO3)0.5(OH)·0.11H2O ANWAs was completely converted to the black Co3O4 ANTAs thin film by alkaline treatment. After the decoration of TiO2, the TiO2/Co3O4 ANTAs electrode exhibits a much higher current response to glucose compared with the Co3O4 ANTAs. Importantly, this neotype composite structure of Co3O4 enhances the glucose sensing performance by increasing specific surface area, additional reactive sites and synergistic effect, which make the TiO2/Co3O4 glucose sensor show a high sensitivity of 2008.82 μA mM(-1) cm(-2), a fast response time (less than 5s) and a detection limit as low as 0.3396 μM (S/N=3). The TiO2/Co3O4 ANTAs modified electrode exhibits a high selectivity for glucose in human serum, against ascorbic acid and uric acid.

In situ transmission electron microscopy study of the electrochemical sodiation process for a single CuO nanowire electrode

In this work, an in situ transmission electron microscopy (TEM) study of the electrochemically driven sodiation and desodiation of a CuO nanowire (NW) was performed. Upon sodiation, Na ions first reacted with CuO, yielding a mixture of Cu, Cu2O, and Na2O, and then some Cu2O was subsequently reduced into nanocrystal Cu. The final sodiation product was nanocrystalline Cu mixed with Na2O and Cu2O. Upon extraction of Na+, the nanocrystalline Cu first oxidized into Cu2O and finally transformed back to nanocrystalline CuO. The volume of the CuO NW was found to expand markedly during the first sodiation, but the morphology of the NW remained unchanged during the following cycles. The mechanism by which high-performance CuO NW anodes are used for rechargeable Na ion batteries was analyzed by carrying out an in situ TEM technique based on our results, and this study may be beneficial for designing the optimal structure of the CuO anode, improving its cycle performance, and making CuO more feasible for Na ion batteries.

Cupric oxide nanowires on three-dimensional copper foam for application in click reaction

Readily prepared CuO nanowires (CuO NWs) have been found to be effective heterogeneous catalysts for the 1,3-dipolar cycloaddition (CuAAC) reaction without using any additional support and bases. Examination of CuO nanowire catalysts synthesized at various temperatures showed that the use of CuO-600 catalyst was the best choice for the success of the present click reaction. Not only aromatic and heteroaromatic alkynes but also alkylalkynes were catalyzed regioselectively, affording triazoles in excellent yields. Furthermore, we have identified that the reaction proceeded in a heterogeneous manner. It is noteworthy that the CuO-600 catalyst can be easily recovered and reused nine times.

In situ TEM observing structural transitions of MoS2 upon sodium insertion and extraction

In this study, the sodiation and desodiation processes of MoS2 were characterized by using an in situ TEM technique. The structural evolution of MoS2 and its performance in a coin-type cell are recognized. Our findings provide a fundamental understanding of the reaction mechanism of MoS2 as anode for Na ion batteries.

Shear-Assisted Production of Few-Layer Boron Nitride Nanosheets by Supercritical CO 2 Exfoliation and Its Use for Thermally Conductive Epoxy Composites

Boron nitride nanosheets (BNNS) hold the similar two-dimensional structure as graphene and unique properties complementary to graphene, which makes it attractive in application ranging from electronics to energy storage. The exfoliation of boron nitride (BN) still remains challenge and hinders the applications of BNNS. In this work, the preparation of BNNS has been realized by a shear-assisted supercritical CO2 exfoliation process, during which supercritical CO2 intercalates and diffuses between boron nitride layers, and then the exfoliation of BN layers is obtained in the rapid depressurization process by overcoming the van der Waals forces. Our results indicate that the bulk boron nitride has been successfully exfoliated into thin nanosheets with an average 6 layers. It is found that the produced BNNS is well-dispersed in isopropyl alcohol (IPA) with a higher extinction coefficient compared with the bulk BN. Moreover, the BNNS/epoxy composite used as thermal interface materials has been prepared. The introduction of BNNS results in a 313% enhancement in thermal conductivity. Our results demonstrate that BNNS produced by supercritical CO2 exfoliation show great potential applications for heat dissipation of high efficiency electronics.