Yanqiong Li

Hydrothermal synthesis of SnO2 nanocubes and nanospheres and their gas sensing properties

In this work, we reported successful synthesis of SnO2 nanocubes and nanospheres via a facile hydrothermal technique. The as-obtained SnO2 nanostructures have been characterized by X-ray diffraction and field-emission scanning electron microscopy. The formation mechanism of aforementioned SnO2 nanostructures has been proposed in detail, especially SnO2 nanaocubes, which has been systematically investigated by varying the reaction time and the surfactant SDS play a key role in growth process of nanocubes. Furthermore, the gas sensing properties of as-prepared SnO2 nanostructures have been tested towards ethanol. Interestingly, it is noted that gas sensing performance of nanocubes are superior to nanospheres, which certified that the gas sensing properties can be enhanced by controlling the morphologies and the SnO2 nanocubes maybe a promising candidate based materials in the fields of gas sensors.

Hierarchical WO3 porous microspheres and their sensing properties

Materials with porous and hierarchical structures are of great interest for potential use in energy and environmental applications. Here, we fabricate the WO3 microspheres which consist of the nanosheets by using a simple hydrothermal process. The likely formation mechanism of the porous microspheres is proposed based on the time-dependent experiments. As a consequence of the unique hierarchical and porous architecture, the microspheres show excellent gas sensing properties due to their large amount of petals and pores, which benefited for the gas diffusion.

Synthesis of SnO2 flower-like architectures by varying the hydrothermal reaction time

We successfully synthesized hierarchical SnO2 flower-like architectures assembled with nanorods via a facile hydrothermal route under mild condition. The structures and morphologies of the obtained hierarchical architectures were characterized by means of powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. By varying hydrothermal reaction time, we obtained the sphere-like and flower-like SnO2. The evolution that the morphology changing from sphere-like to flower-like was systematically investigated. Moreover, the mechanism of formation for this structure was proposed in detail.

Net-like MoO3 porous architectures: synthesis and their sensing properties

Porous architectures consisting of three-dimensional nanostructures are of great interest for potential applied in gas-sensing. Herein, novel net-like MoO3 porous architectures were successfully synthesized via a facile hydrothermal method. The as-prepared MoO3 porous architectures were in fact assembled by numerous nanorods to form a net. The results found that the existence of chromic chloride hexahydrate played a significant role in governing morphologies of MoO3 during hydrothermal process. Based on comparative studies, a possible formation mechanism was also proposed in detail. Further, gas-sensing measurement showed that the well-defined net like MoO3 porous architectures exhibited the excellent gas sensing properties.

Hydrothermal synthesis of different SnO2 nanosheets with CO gas sensing properties

In this work, 2D SnO2 nanosheets were synthesized via a polyvinylpyrrolidone (PVP)-assisted hydrothermal method. X-ray diffraction and scanning electron microscopy were used to examine the chemical composition and nanostructures. It was found that the concentration of PVP played a critical role in governing the assembly process of nanostructures. Further, their gas-sensing performances were investigated comprehensively. The nanosheet-III structures were found to show the most superior gas-sensing properties due to their largest specific surface and fashionable assembly.

Hydrothermal fabrication of WO3·H2O with varied morphologies and their gas sensing performances

Abstract WO3·H2O with varied morphologies were successfully fabricated via a facile hydrothermal process with the assistance of additive agents. X-ray powder diffraction and field-emission scanning electron microscopy were used to characterize samples. Based on the experimental results, the formation process of WO3·H2O as well as the function of additive agents were systematically investigated. Meanwhile, gas sensing researches were carried out on the annealed samples. All samples were detected a high sensitivity towards the ethanol and the corresponding gas sensing mechanism was established.

Synthesis and gas sensing properties of novel SnO2 nanorods

We report the microstructures and gas sensing properties of two novel SnO2 nanorods prepared by hydrothermal method with the utilizing of cetyltrimethylammonium bromide and polyethylene glycol. The structures and morphologies of the dense and porous nanorods were characterized by means of powder X-ray diffraction and scanning electron microscopy. The gas sensing performances towards ethanol of the two samples were investigated. The results show that the porous SnO2 nanorods display excellent gas response to ethanol, indicating SnO2 as a potential gas sensing material for broad applications.

Synthesis and growth mechanism of CuO nanostructures and their gas sensing properties

CuO nano-particles, nano-rods, nano-sheets and nano-flowers were synthesized by the hydrothermal routes with copper salts under different additions. The obtained samples were characterized by X-ray diffraction and scanning electron microscopy. We investigated the effects of precursors on the formation of CuO with different morphologies and proposed their possible formation mechanisms. In addition, the obtained CuO nano-flowers are found to show better sensing performances than the other three low-dimensional CuO nanostructures. Our results also demonstrate that gas sensing properties of nanocrystals can be significantly improved by tailoring shape and morphology of the nanocrystals. The CuO nano-flowers may hold substantial promise in low-dimensional gas-sensing applications.

A Review of Electrode for Rechargeable Magnesium Ion Batteries

Rechargeable magnesium ion batteries with their intrinsic advantages, such as high capacity, low reduction potential and low cost, have been a major candidate for next generation batteries beyond lithium ion batteries. Although some researches have been done in this area, it is still at its early stage hindered by sluggish kinetics and development of electrodes. This review is aimed at exhibiting the key advancement of the cathodes and anodes. Currently used cathodes, Chevel phase, V₂O5, MnO₂ and MoS₂ are detailed introduced. Currently used anodes have also been summarized, in particular, we highlight Mg-ion insertion-type anode materials (e.g., Bi, Sn) of MIB, which provides a new way of thinking. Furthermore, the mechanism for Mg insertion/deinsertion and several methods to improve the electrochemical properties for these electrode materials, mainly including reducing the particle size and changing the morphology, have been showed.

Mesoporous Fe 3 O 4 /NiO composite microspheres with p–n heterojunction for a high-performance ethanol sensor

A highly sensitive nanostructured sensing material has been fabricated successfully by designing Fe3O4/NiO composite with p–n heterojunction. The morphology and structure of as-obtained Fe3O4/NiO composites were analyzed by various kinds of techniques. A bifunctional sensing mechanism of the composites was proposed in which the combined effects of existence of p-NiO/n-Fe3O4 heterojunction and the ascendant architecture contributed to an improvement in the ethanol characteristics.