Considering the mechnoelectrical coupling, the localization of SH-waves in disordered periodic layered piezoelectric structures is studied. The waves propagating in directions normal and tangential to the layers are c...Considering the mechnoelectrical coupling, the localization of SH-waves in disordered periodic layered piezoelectric structures is studied. The waves propagating in directions normal and tangential to the layers are considered. The transfer matrices between two consecutive unit cells are obtained according to the continuity conditions. The expressions of localization factor and localization length in the disordered periodic structures are presented. For the disordered periodic piezoelectric structures, the numerical results of localization factor and localization length are presented and discussed. It can be seen from the results that the frequency passbands and stopbands appear for the ordered periodic structures and the wave localization phenomenon occurs in the disordered periodic ones, and the larger the coefficient of variation is, the greater the degree of wave localization is. The widths of stopbands in the ordered periodic structures are very narrow when the properties of the consecutive piezoelectric materials are similar and the intervals of stopbands become broader when a certain material parameter has large changes. For the wave propagating in the direction normal to the layers the localization length has less dependence on the frequency, but for the wave propagating in the direction tangential to the layers the localization length is strongly dependent on the frequency.展开更多
Among the substantial amount of photocatalyst materials,TiO2 has been enthusiastically studied for a few decades due to its outstanding photocatalytic activity and stability.Recently,black TiO2 consisting of approxima...Among the substantial amount of photocatalyst materials,TiO2 has been enthusiastically studied for a few decades due to its outstanding photocatalytic activity and stability.Recently,black TiO2 consisting of approximately 2 nm of thin disorder layer around the surface showed surprisingly high solar hydrogen generation ability.The disorder layer of TiO2 can enhance its light absorption,charge separation,and surface reaction abilities,however exact fundamentals of photocatalytic water-splitting pathways are still ambiguous.Herein,recent progress and investigations on exact functions of disorder layer and its application in photocatalytic CO2 reduction will be discussed.Throughout the comprehensive studies on disorder layer of TiO2,disorder engineering on photocatalyst materials will suggest the further extension of developing solarfuel production technologies.展开更多
基金The project supported by National Natural Science Foundation of China (10632020, 10672017 and 20451057)
文摘Considering the mechnoelectrical coupling, the localization of SH-waves in disordered periodic layered piezoelectric structures is studied. The waves propagating in directions normal and tangential to the layers are considered. The transfer matrices between two consecutive unit cells are obtained according to the continuity conditions. The expressions of localization factor and localization length in the disordered periodic structures are presented. For the disordered periodic piezoelectric structures, the numerical results of localization factor and localization length are presented and discussed. It can be seen from the results that the frequency passbands and stopbands appear for the ordered periodic structures and the wave localization phenomenon occurs in the disordered periodic ones, and the larger the coefficient of variation is, the greater the degree of wave localization is. The widths of stopbands in the ordered periodic structures are very narrow when the properties of the consecutive piezoelectric materials are similar and the intervals of stopbands become broader when a certain material parameter has large changes. For the wave propagating in the direction normal to the layers the localization length has less dependence on the frequency, but for the wave propagating in the direction tangential to the layers the localization length is strongly dependent on the frequency.
基金Sungsoon Kim and Yoonjun Cho contributed equally to this study.This study was supported by the National Research Foundation of Korea(2015M1A2A2074663,NRF-2019M1A2A2065612,and 2019R1A4A1029237)This study was also supported by the Korea Institute of Energy Technology Evaluation and Planning and the Ministry of Trade,Industry&Energy of the Republic of Korea(No.20163010012450).
文摘Among the substantial amount of photocatalyst materials,TiO2 has been enthusiastically studied for a few decades due to its outstanding photocatalytic activity and stability.Recently,black TiO2 consisting of approximately 2 nm of thin disorder layer around the surface showed surprisingly high solar hydrogen generation ability.The disorder layer of TiO2 can enhance its light absorption,charge separation,and surface reaction abilities,however exact fundamentals of photocatalytic water-splitting pathways are still ambiguous.Herein,recent progress and investigations on exact functions of disorder layer and its application in photocatalytic CO2 reduction will be discussed.Throughout the comprehensive studies on disorder layer of TiO2,disorder engineering on photocatalyst materials will suggest the further extension of developing solarfuel production technologies.
