Prof Zhimao Yang
Department of Materials Physics
School of Science
Xian Jiaotong University
Xianning West Road #28
Xian, 710049, Shaanxi
· Fangzhao Pu, Chuncai Kong, Jian Lv, Bo Ma, Wanqi Zhang, Xiaojing Zhang, Sen Yang, Hong Jin*, Zhimao Yang*, CuO ultrathin nanosheets decorated reduced graphene oxide as a high performance anode for lithium-ion batteries, Journal of Alloys and Compounds, 805 (2019) 355-362
Two-dimensional (2D) nanocomposites, based on graphene and transition metal oxides, hold great promise as high-performance electrode materials for next-generation lithium-ion batteries. Herein, a novel 2D CuO/RGO has been constructed by CuO ultrathin nanosheets and reduced graphene oxides (RGO) through in-situ oxidizing the Cu/RGO nanocomposite with hydrogen peroxide. CuO nanosheets with a thickness of 1.17e1.57 nm are uniformly and tightly anchored on the RGO surface without aggregation and thus the as-prepared CuO/RGO nanosheets electrode show strong interfacial coupling and fast electron transfer. Electrochemical characterizations reveal that the CuO/RGO nanocomposite electrode exhibits a remarkably enhanced cycling performance and rate performance. At the current density of 0.1C, the initial discharge capacity of 811 mAh/g has been delivered by CuO/RGO nanosheets electrode and the coulombic efficiency maintains 99.44% after 100 cycles. Moreover, the CuO/RGO nanosheets exhibit a stable specific capacity of 386 mAh/g after 200 cycles at 3C. In addition, the as-prepared CuO/RGO nanocomposite electrode exhibited excellent rate performance and lower charge transfer resistance. The current study presents a feasible route to fabricate nanosheets electrode materials for nextgeneration energy storage devices.
· Wang Mei Xiang, Chen Yong Mei*, Gao Yang, Hu Chen, Hu Jian, Tan Li*, Yang Zhimao*, Rapid Self-Recoverable Hydrogels with High Toughness and Excellent Conductivity, ACS Applied Materials & Interfaces, 2018, 10, 26610-26617
Hydrogels as soft and wet materials have attracted much attention in sensing and flexible electronics. However, traditional hydrogels are fragile or have unsatisfactory recovery capability, which largely limit their applications. Here, a novel hydrogen bond based sulfuric acid−poly(acrylic acid) (PAA)/poly(vinyl alcohol) physical hydrogel is developed for addressing the above drawbacks. Sulfuric acid serves two functions: one is to inhibit the ionization of carboxyl groups from PAA chains to form more hydrogen bonds and the other is to provide conductive ions to promote conductivity of hydrogel. Consequently, the hydrogel obtains comprehensive mechanical properties, including extremely rapid self-recovery (strain = 1, instantly self-recover; strain = 20, self-recover within 10 min), high fracture strength (3.1 MPa), and high toughness (18.7 MJ m−3). In addition, we demonstrate this hydrogel as a tretchable ionic cable and pressure sensor to exhibit stable operation after repeated loadings. This work provides a new concept to synthesize physical hydrogels, which will hopefully expand applications of hydrogel in stretchable electronics.
· Chuncai Kong, Bo Ma, Ke Liu, Weixin Zhang, Zhimao Yang*, Continuous UV irradiation synthesis of ultra-small Au nanoparticles decorated Cu2O with enhanced photocatalytic activity, Composites Communications, 9 (2018) 27–32
Noble metal nanoparticles (NPs) with controlled size and shape can be easily prepared by UV irradiation at room temperature. In this work, ultra-small Au NPs were successfully continuously synthesized via an UV irradiation approach, and the synthesis conditions of Au NPs with the size of 1.8 nm have been optimized to be an exposure time of 1.4 min, a HAuCl4 precursor concentration of 0.8mM and a pH value of 10.4. The growth dynamics of Au NPs was investigated under different exposing time of the electron beam in transmission electron microscopy (TEM), revealing the formation of NPs via the oriented attachment of individual nanoparticles. In addition, well dispersed ultra-small Au NPs decorated Cu2O composites were obtained from this in-situ strategy and showed an enhanced photocatalytic activity compared with that of Au-free oxides and Au- Cu2O from direct replacement method.
· Shaodong Sun*, Xiaojing Zhang, Qing Yang, Shuhua Liang*, Xiaozhe Zhang, Zhimao Yang*, Cuprous oxide (Cu2O) crystals with tailored architectures: A comprehensive review on synthesis, fundamental properties, functional modifications and applications, Progress in Materials Science, 96, 111–173, 2018
Better understanding the crystal-facet engineering of a crystal with tailored architecture has demonstrated a significant implication for rational design and synthesis of promising micro-/nanostructure. In the past decades, extensive investigations have been devoted tothe development of cuprous oxide (Cu2O) crystals with tailored architectures, which can provide a meritorious platform for not only evealing the structure-property performance relationship and but also improving the performances in their practical applications. Several previous reviews have mainly reported the partial summaries of the advances in facet-dependent properties of Cu2O crystals. However, a comprehensive summary on Cu2O crystals is lacking and highly desirable to further promote the development of function-oriented Cu2O-based micro-/nanostructures. In this review, we will comprehensively highlight the important progresses in Cu2O crystals with tailored architectures, including the synthetic strategies and corresponding growth mechanisms, the fundamental properties of different crystallographic facets, the functional modifications (including doping and hybridization), and their potential applications. Several urgent issues and perspective are also discussed.
· Shaodong Sun, Yuexia Sun, Anran Chen, Xiaozhe Zhang, Zhimao Yang*, Nanoporous copper oxide ribbon assembly of free-standing nanoneedles as biosensors for glucose, Analyst, 2015,140, 5205-5215
Inspired by a sequential hydrolysis–precipitation mechanism, morphology-controllable hierarchical cupric oxide (CuO) nanostructures are facilely fabricated by a green water/ethanol solution-phase transformation of Cux(OH)2x−2(SO4) precursors in the absence of any organic capping agents and without annealing treatment in air. Antlerite Cu3(OH)4(SO4) precursors formed in a low volume ratio between water and ethanol can transform into a two-dimensional (2D) hierarchical nanoporous CuO ribbon assembly of free-standing nanoneedle building blocks and hierarchical nanoneedle-aggregated CuO flowers. Brochantite Cu4(OH)6(SO4) precursors formed in a high volume ratio between water and ethanol can transform into hierarchical nanoplate-aggregated CuO nanoribbons and nanoflowers. Such 2D hierarchical nanoporous CuO ribbons serving as a promising electrode material for nonenzymatic glucose detection show high sensitivity, a low detection limit, fast amperometric response and good selectivity. Significantly, this green water-induced precursor-hydrolysis method might be used to control effectively the growth of other metal oxide micro-/nanostructures.
Linli Tang, Jian Lv, Shaodong Sun, Xiaozhe Zhang, Chuncai Kong, Xiaoping Song and Zhimao Yang*, Facile hydroxyl-assisted synthesis of morphological Cu2O architectures and their shape-dependent photocatalytic performances, New J. Chem, 2014, 38, 4656-4660
An interesting morphology-evolution of Cu2O from cubic, edgetruncated cubic, edge- and corner-truncated octahedral, truncated octahedral, and finally to octahedral architectures was readily achieved by adjusting the concentration of hydroxyl. When evaluated for their photocatalytic performances, these polyhedral Cu2O crystals manifest shape-dependent properties.
We have demonstrated a facile anion-assisted strategy for the synthesis of nanoparticle-aggregated CuO nanoellipsoids. Structural and morphological evolutions were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), andfield-emission scanning electron microscopy (FESEM). The nanoparticle-aggregated CuO nanoellipsoids serve as a promising electrode material for a non-enzymatic glucose biosensor which shows high sensitivity, good reproducibility, a fast amperometric response and good selectivity. The study is of great importance in the bottom-up assembly of tunable ordered architectures, and offers a chance to understand the formation mechanism and fundamental significance of an anion-assisted strategy for the synthesis of metal oxides. Significantly, it is believed that the anion-assisted synthetic approach reported
here could provide a facile way to design more novel metal oxide architectures with well-defined shapes.
In this report, a novel type of a hollow CuO polyhedron-modified electrode for sensitive nonenzymatic glucose detection has been fabricated by a templating approach. The morphologies and structures were characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectrum and X-ray photoelectron spectroscopy (XPS). These results show that the as-prepared hollow CuO consists of numerous CuO nanoplates. The electrochemical performance for glucose detection was investigated by cyclic voltammetry and chronoamperometry. The hollow CuO polyhedron-modified electrode exhibits a high sensitivity of 1112 μA mM-1 cm-2 with a detection limit of 0.33 mM (S/N = 3) at +0.55 V, and the linear range is up to 4 mM. Moreover, the hollow CuO polyhedron-modified electrode is highly resistant to the interference from interfering species such as sodium chloride (NaCl), ascorbic acid (AA) and uric acid (UA). The hollow CuO polyhedron-modified electrode exhibits high sensitivity, low detection limit, good stability and fast response towards the oxidation of glucose; thus, it may be a promising nonenzymatic glucose sensor.