In the process of grid-connected wind and solar power generation,there are problems of high rate of abandoning wind and light and insufficient energy.In order to solve these problems,we construct a grid-connected wind...In the process of grid-connected wind and solar power generation,there are problems of high rate of abandoning wind and light and insufficient energy.In order to solve these problems,we construct a grid-connected wind-solar hydrogen storage(alkaline electrolyzer(AE)-hydrogen storage tank-battery-proton exchange membrane fuel cell(PEMFC))coupled system architecture.A grid-connected compensation/consumption hierarchical control strategy based on wind-solar hydrogen coupling is proposed.During the grid-connected process of wind and solar power generation,the upper-level control allocates power reasonably to the hydrogen energy storage system by dispatching the power of wind and solar power generation.At the same time,the control strategy ensures that the pressure of the hydrogen storage tank is within the safety range limit,and the lower control completes the control of the duty cycle of the converter in the system.Due to the randomness of wind and light,the hydrogen energy storage system is divided into three working conditions,namely compensation,balance and consumption,and five working modes.The simulation results show that the hydrogen energy storage system compensates for 40%of the power shortage,and consumes 27.5%of the abandoned wind and solar energy,which improves the utilization rate of clean energy.展开更多
We study molybdenum disulfide (MoS2) structures generated by folding single-layer and bilayer MoS2 flakes. We find that this modified layer stacking leads to a decrease in the interlayer coupling and an enhancement ...We study molybdenum disulfide (MoS2) structures generated by folding single-layer and bilayer MoS2 flakes. We find that this modified layer stacking leads to a decrease in the interlayer coupling and an enhancement of the photoluminescence emission yield. We additionally find that folded single-layer MoS2 structures show a contribution to photoluminescence spectra of both neutral and charged excitons, which is a characteristic feature of single-layer MoS2 that has not been observed in multilayer MoS2. The results presented here open the door to fabrication of multilayered MoS2 samples with high optical absorption while maintaining the advantageous enhanced photoluminescence emission of single-layer MoS2 by controllably twisting the MoS2 layers.展开更多
Hybrid structures composed of layered materials have received much attention due to their exceptional tunable optical, electronic and catalytic properties. Here, we describe a hydrothermal strategy for coupling vertic...Hybrid structures composed of layered materials have received much attention due to their exceptional tunable optical, electronic and catalytic properties. Here, we describe a hydrothermal strategy for coupling vertical ZnO nanorods on MoS2 monolayers without a catalyst. These vapor-solid-grown MoS2 monolayers aid in growing vertical ZnO nanorods via epitaxy. Enhanced Raman and photoluminescence emissions were observed from the MoS2 monolayers under the ZnO nanorods in these coupled structures, which was attributed to the light antenna effect of the ZnO nanorods. These hybrid and incorporation protocols for layered materials will provide new perspectives and opportunities for promoting the construction of heterojunctions with adjustable layered structures leading to fascinating fundamental phenomena and advanced devices.展开更多
A phenomenon about optical bistability is successfully investigated in a layered structure consisting of a silver film with Kerr medium and a silver grating sandwiched between semi-infinite linear dielectrics.This typ...A phenomenon about optical bistability is successfully investigated in a layered structure consisting of a silver film with Kerr medium and a silver grating sandwiched between semi-infinite linear dielectrics.This type of structure can lead to the optical bistability phenomena occurring in reflection and transmission.There exists an optimal thickness of the metal grating that can cut off the effect of the near-field enhancement and may have the lowest effect on conversion from surface plasmon to light.This structure can realize the functions of the beam splitter and the polarization splitter and will be essential for future classical and quantum information processing.展开更多
基金Xi’an Key Laboratory of Clean Energy(No.2019219914SYS014CG036)Natural Science Foundation of Xi’an City(No.XA2020-CXRCFW-0247)Yulin Industry-University-Research Cooperation Project(No.2019-173)。
文摘In the process of grid-connected wind and solar power generation,there are problems of high rate of abandoning wind and light and insufficient energy.In order to solve these problems,we construct a grid-connected wind-solar hydrogen storage(alkaline electrolyzer(AE)-hydrogen storage tank-battery-proton exchange membrane fuel cell(PEMFC))coupled system architecture.A grid-connected compensation/consumption hierarchical control strategy based on wind-solar hydrogen coupling is proposed.During the grid-connected process of wind and solar power generation,the upper-level control allocates power reasonably to the hydrogen energy storage system by dispatching the power of wind and solar power generation.At the same time,the control strategy ensures that the pressure of the hydrogen storage tank is within the safety range limit,and the lower control completes the control of the duty cycle of the converter in the system.Due to the randomness of wind and light,the hydrogen energy storage system is divided into three working conditions,namely compensation,balance and consumption,and five working modes.The simulation results show that the hydrogen energy storage system compensates for 40%of the power shortage,and consumes 27.5%of the abandoned wind and solar energy,which improves the utilization rate of clean energy.
文摘We study molybdenum disulfide (MoS2) structures generated by folding single-layer and bilayer MoS2 flakes. We find that this modified layer stacking leads to a decrease in the interlayer coupling and an enhancement of the photoluminescence emission yield. We additionally find that folded single-layer MoS2 structures show a contribution to photoluminescence spectra of both neutral and charged excitons, which is a characteristic feature of single-layer MoS2 that has not been observed in multilayer MoS2. The results presented here open the door to fabrication of multilayered MoS2 samples with high optical absorption while maintaining the advantageous enhanced photoluminescence emission of single-layer MoS2 by controllably twisting the MoS2 layers.
基金This work was funded by the National Basic Research Program of China (Nos. 2012CB934301 and 2011CBA00905), the National Natural Science Foundation of China (Nos. 61376016, 61290304 and 61275114) and CAS (No. KSZD-EW-Z-018). The authors thank Y. L. Jing, X. H. Zhou and T. X. Li for helpful discussions and technical support.
文摘Hybrid structures composed of layered materials have received much attention due to their exceptional tunable optical, electronic and catalytic properties. Here, we describe a hydrothermal strategy for coupling vertical ZnO nanorods on MoS2 monolayers without a catalyst. These vapor-solid-grown MoS2 monolayers aid in growing vertical ZnO nanorods via epitaxy. Enhanced Raman and photoluminescence emissions were observed from the MoS2 monolayers under the ZnO nanorods in these coupled structures, which was attributed to the light antenna effect of the ZnO nanorods. These hybrid and incorporation protocols for layered materials will provide new perspectives and opportunities for promoting the construction of heterojunctions with adjustable layered structures leading to fascinating fundamental phenomena and advanced devices.
基金supported by National Basic Research Program of China(Grant No.2010CB923202)
文摘A phenomenon about optical bistability is successfully investigated in a layered structure consisting of a silver film with Kerr medium and a silver grating sandwiched between semi-infinite linear dielectrics.This type of structure can lead to the optical bistability phenomena occurring in reflection and transmission.There exists an optimal thickness of the metal grating that can cut off the effect of the near-field enhancement and may have the lowest effect on conversion from surface plasmon to light.This structure can realize the functions of the beam splitter and the polarization splitter and will be essential for future classical and quantum information processing.