Thermalfatiguebehaviorsof Nibased alloychromium carbidecompositecoating madeby a vacu um fusionsintering method are discussed. Resultsshowedthatthermalfatiguebehaviorisassoci ated with cyclic uppertemperature and ...Thermalfatiguebehaviorsof Nibased alloychromium carbidecompositecoating madeby a vacu um fusionsintering method are discussed. Resultsshowedthatthermalfatiguebehaviorisassoci ated with cyclic uppertemperature and coating thickness. Asthe thickness of coating decreases,thethermalfatigueresistanceincreases. Thethermalfatigueresistancecuts down with thether malcyclic uppertemperature rising. Thecrack growth rate decreases with theincreasein cyclicnumber untilcrackarrests. Thetractofthermalfatiguecrackcracksalongtheinterfacesof phas es. Thecompositecoating possesseshigheroxidation resistance.展开更多
The traditional single material with two-dimensional （2D） biomimetic moth-eye structures is limited by its narrowband antireflection and single functional capability. To overcome these disadvantages, we exploited we...The traditional single material with two-dimensional （2D） biomimetic moth-eye structures is limited by its narrowband antireflection and single functional capability. To overcome these disadvantages, we exploited wet etching and hydrothermal synthesis coupled with chemical oxidation for fabricating a three- dimensional （3D） biomimetic moth-eye coating with ternary materials （polypyrrole nanoparticles, TiO2 nanorods, and Si micropyramids, i.e., PPy/TiOa/Si-p）. This coating reduced the reflectivity to 〈4% at wavelengths ranging from 200 to 2,300 nm and exhibited remarkable superhydrophilidty with a low water contact angle of 1.8°. Moreover, the composite coating had double p-n heterojunctions, allowing the high-efficiency separation of photogenerated carriers. The photo- current density of PPy/TiO2/Si-p was more than three times higher than that of TiO2/Si-p at a positive potential of 1.5 V. The proposed method provides a means to enhance solar energy conversion.展开更多
基金This work was supported by the National Natural Science Foundation of China （Nos. 21401079, 21501069, and 21671081）, Fundamental Research Funds for the Central Universities （No. JUSRP51626B）, and Natural Science Foundation of Jiangsu Province （Nos. BK20140158 and BK20161128）.
文摘The traditional single material with two-dimensional （2D） biomimetic moth-eye structures is limited by its narrowband antireflection and single functional capability. To overcome these disadvantages, we exploited wet etching and hydrothermal synthesis coupled with chemical oxidation for fabricating a three- dimensional （3D） biomimetic moth-eye coating with ternary materials （polypyrrole nanoparticles, TiO2 nanorods, and Si micropyramids, i.e., PPy/TiOa/Si-p）. This coating reduced the reflectivity to 〈4% at wavelengths ranging from 200 to 2,300 nm and exhibited remarkable superhydrophilidty with a low water contact angle of 1.8°. Moreover, the composite coating had double p-n heterojunctions, allowing the high-efficiency separation of photogenerated carriers. The photo- current density of PPy/TiO2/Si-p was more than three times higher than that of TiO2/Si-p at a positive potential of 1.5 V. The proposed method provides a means to enhance solar energy conversion.
