In this Review, we aim to provide an updated summary of the research related to hollow micro- and nanostructures, covering both their synthesis and their applications. After a brief introduction to the definition and classification of the hollow micro-/nanostructures, we discuss various synthetic strategies that can be grouped into three major categories, including hard templating, soft templating, and self-templating synthesis. For both hard and soft templating strategies, we focus on how different types of templates are generated and then used for creating hollow structures. At the end of each section, the structural and morphological control over the product is discussed. For the self-templating strategy, we survey a number of unconventional synthetic methods, such as surface-protected etching, Ostwald ripening, the Kirkendall effect, and galvanic replacement. We then discuss the unique properties and niche applications of the hollow structures in diverse fields, including micro-/nanocontainers and rea...

Synthesis, Properties, and Applications of Hollow Micro-/Nanostructures

A humidity sensor based on a single SnO2 nanowire was fabricated. This sensor has fast and sensitive response to relative humidity (RH) in air from a wide range of atmospheres at 30 °C. The response sensitivity of the sensor to RH is linear to 90%.

/pdf/high-sensitivity-humidity-sensor-based-on-a-single-sno2-190fmwqcpf.pdf

High-Sensitivity Humidity Sensor Based on a Single SnO2 Nanowire

Diameter-controlled Growth of Single-crystalline In2O3 Nanowires and Their Electronic Properties

Book reviewsComposite materials: fatigue and fracture: Edited by: H.T. Hahn ASTM STP 907, 1986 (£64.00)

Laser peening without protective coating (LPPC) has been applied to water-immersed SUS304 (Type 304) and SUS316L (Type 316L) austenitic stainless steels. The surface residual stress of both materials was converted from tensile to compressive of several hundreds of megapascals by LPPC with a Q-switched and frequency-doubled Nd:YAG laser. The depth of the compressive residual stresses after LPPC exceeded 1 mm from the surface. Accelerating stress corrosion cracking (SCC) tests in a high-temperature and corrosive-water environment showed that LPPC completely prevented the SCC initiation of sensitized SUS304. SCC tests of pre-cracked samples were also performed for SUS304, which indicated that LPPC inhibits the propagation of the small pre-cracks. Rotating bending tests demonstrated that the fatigue strength of SUS316L with LPPC is enhanced by 1.4–1.7 times compared to that of the reference material at 108 cycles.

Retardation of crack initiation and growth in austenitic stainless steels by laser peening without protective coating

The chemical decomposition of AgOx sandwiched between two ZnS–SiO2 protective layers was an irreversible process. We confirmed that a hollow Ag cylinder, or ring, serving as an aperture, was formed and small Ag particles were precipitated in the center region during the recording process. The small aperture can significantly reduce the laser spot size during the readout process and the strong near-field interaction between precipitated Ag particles and subwavelength marks can effectively enhance the readout signal. That clarifies both the super-resolution effect and the near-field interaction in the super-resolution near-field structure disk.

Recording and readout mechanisms of super-resolution near-field structure disk with a silver oxide mask layer

http://web.nchu.edu.tw/pweb/users/ycho22081/research/5053.pdf

Fatigue crack initiation and multiplication of unnotched titanium matrix composites

Adding In into Sb70Te30 recording film can improve the archival stability. However, initializing ability and recording sensitivity will be scarified, and ablation effect will be enhanced. Recording bits could only be smoothly switched between the amorphous and crystalline states with an adequate value of reduced activation energy

http://web.nchu.edu.tw/pweb/users/ycho22081/research/6680.pdf

Thermal- and Laser-Induced Order–Disorder Switching of In-Doped Fast-Growth Sb $_{70}$ Te $_{30}$ Phase-Change Recording Films

The effect of fiber coating on the fatigue crack initiation and multiplication of an unnotched SCS-6 fiber-reinforced titanium aluminide (Ti 3 Al) matrix composite was investigated. The initiation and growth of each individual matrix crack, the evolution of matrix crack density and stiffness degradation of the composite with Ag/Ta-coated fibers were characterized quantitatively, and compared with those of the composite with uncoated fibers. The results showed that the composite with Ag/Ta-coated fibers exhibited a shorter crack initiation life, higher number of matrix cracks, and higher crack growth rate than the composite with uncoated fibers. Therefore, a higher matrix crack density and a lower residual stiffness were found in the composite with coated fibers during fatigue loading. The high interfacial cracking density and high interfacial bond strength in the Ag/Ta-coated SCS-6/Ti 3 Al composite is believed to be responsible for its poor fatigue damage resistance. Finally, an interface-controlled fatigue cracking model is used to predict the evolution of matrix crack density and residual stiffness of the composite under fatigue loading.

http://web.nchu.edu.tw/pweb/users/ycho22081/research/5055.pdf

Effect of fiber coating on the fatigue crack initiation and multiplication of unnotched SCS-6/Ti3Al composites

We have investigated the optothermal property and decomposition characteristics of PtO(x) ultrathin film protected by ZnS-SiO2 layers and effects of the constituent phases of PtO(x) on super-resolution capability and read stability of the super-RENS disk. All the ZnS-SiO2/PtO(x)/ZnS-SiO2 multilayers exhibited a steep reflectivity drop at the temperature range between 265 and 350 degrees C, corresponding to the decomposition of PtO(x). The decomposition temperature of the 4-nm-thick PtO(x) ultrathin film protected by ZnS-SiO2 layers was much lower than those obtained in thick PtO(x) films without protection. The activation energy for thermal decomposition was approximately 1.3 eV. Both the decomposition temperature and activation energy for thermal decomposition were unaffected by the constituent phases of PtO(x). Carrier to noise ratios (CNR) of over 40 dB for mark size of 150 nm were achieved in all super-resolution near-field structure (super-RENS) disks, while the super-resolution readout was limited to 2.5 x 10(3) approximately 4.5 x 10(4) cycles. The effect of constituent phases of PtO(x) on the super-resolution capability of super-RENS disk with a PtO(x) mask layer was minimal. However, as the constituent phases of PtO(x) mask layer transformed from a mixture of Pt and PtO, to pure PtO, and then to a mixture of PtO and PtO2, the readout stability of super-RENS disk increased dramatically since less heat was absorbed by the PtO(x) mask layer composed of PtO and PtO2 during the readout process, prohibiting the diffusion of materials inside the bubble to the GeSbTe phase change layer.

Yung-Chiun Her

Papers

Recording and readout mechanisms of super-resolution near-field structure disk with a silver oxide mask layer

Fatigue crack initiation and multiplication of unnotched titanium matrix composites

Thermal- and Laser-Induced Order–Disorder Switching of In-Doped Fast-Growth Sb $_{70}$ Te $_{30}$ Phase-Change Recording Films

Effect of fiber coating on the fatigue crack initiation and multiplication of unnotched SCS-6/Ti3Al composites

Optothermal property and decomposition characteristics of PtO(x) ultrathin film sandwiched between ZnS-SiO2 for super-resolution near-field recording.