Hierarchical mesoporous MoO2/Mo2C/C microspheres,which are composed of primary nanoparticles with a size of about 30 nm,have been designed and synthesized through polymer regulation and subsequent carbonization proces...Hierarchical mesoporous MoO2/Mo2C/C microspheres,which are composed of primary nanoparticles with a size of about 30 nm,have been designed and synthesized through polymer regulation and subsequent carbonization processes.The as-synthesized microspheres were characterized by XRD,Raman,SEM,TEM,XPS measurements and so on.It was found that polyethylene glycol acted as a structure-directing agent,mild reducing agent and carbon source in the formation of these hierarchical mesoporous Mo O2/Mo2C/C microspheres.Moreover,the electrochemical property of the microspheres was also investigated in this work.Evaluated as an anode material for lithium ion batteries,the hierarchical mesoporous Mo O2/Mo2C/C electrode delivered the discharge specific capacities of 665 and 588 m Ah/g after 100 cycles at current densities of 100 and 200 m A/g,respectively.The satisfactory cycling performance and controllable process facilitate the practical applications of the hierarchical mesoporous Mo O2/Mo2C/C as a potential anode material in high-energy density lithium-ion batteries.展开更多
The fabrication of a dynamic threshold-2T0C(DT-2T0C) DRAM cell incorporating a ZnO charge-trap layer in the write transistor has been successfully achieved, addressing the negative hold voltage(V_(HOLD)) issue of conv...The fabrication of a dynamic threshold-2T0C(DT-2T0C) DRAM cell incorporating a ZnO charge-trap layer in the write transistor has been successfully achieved, addressing the negative hold voltage(V_(HOLD)) issue of conventional 2T0C DRAM cells using oxide channel layers. The proposed device facilitates dynamic modulation of turn-on voltage(V_(ON)) through an additional SET operation, allowing V_(ON) to shift above 0 V. The retention time in SET operation was extended to 10^(4) s by optimizing the tunneling layer deposition conditions. The device characterization revealed a significant correlation between V_(ON) and both the WRITE speed and the retention properties of the DT-2T0C, verifying the trade-off between WRITE time and retention time. A long retention time over 1000 s was achieved, even under VHOLD of 0 V.展开更多
等离子体处理作为一种高效的表面改性技术,在二维纳米材料/碳基复合结构的形貌调控中具有独特优势。本文通过调控等离子体处理参数(例如气体氛围),研究其对二硫化钨/碳(WS2/C)复合结构表面形貌和缺陷分布的影响。结合扫描电子显微镜(Sca...等离子体处理作为一种高效的表面改性技术,在二维纳米材料/碳基复合结构的形貌调控中具有独特优势。本文通过调控等离子体处理参数(例如气体氛围),研究其对二硫化钨/碳(WS2/C)复合结构表面形貌和缺陷分布的影响。结合扫描电子显微镜(Scanning Electron Microscope,SEM)和基于拉曼光谱的表征,揭示了等离子体处理诱导的WS2边缘选择性和碳纳米纤维骨架的协同效应,提高了复合材料的比表面积和边缘活性位点暴露程度。试验结果表明,参数优化后,等离子体处理可以有效调控WS2纳米晶片在碳纤维骨架中的分散性,并抑制晶片层间堆叠和层片团聚,从而增加边缘位置的暴露程度。该研究为高性能WS2/C复合材料的可控制备提供了新思路,推动其在能源存储与转换领域的实际应用。展开更多
基金supported by the National Natural Science Foundation of China(No.21376251 and 21406233)the National Basic Research Development Program of China(2013CB632600)
文摘Hierarchical mesoporous MoO2/Mo2C/C microspheres,which are composed of primary nanoparticles with a size of about 30 nm,have been designed and synthesized through polymer regulation and subsequent carbonization processes.The as-synthesized microspheres were characterized by XRD,Raman,SEM,TEM,XPS measurements and so on.It was found that polyethylene glycol acted as a structure-directing agent,mild reducing agent and carbon source in the formation of these hierarchical mesoporous Mo O2/Mo2C/C microspheres.Moreover,the electrochemical property of the microspheres was also investigated in this work.Evaluated as an anode material for lithium ion batteries,the hierarchical mesoporous Mo O2/Mo2C/C electrode delivered the discharge specific capacities of 665 and 588 m Ah/g after 100 cycles at current densities of 100 and 200 m A/g,respectively.The satisfactory cycling performance and controllable process facilitate the practical applications of the hierarchical mesoporous Mo O2/Mo2C/C as a potential anode material in high-energy density lithium-ion batteries.
基金supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (RS-2024-00334190)。
文摘The fabrication of a dynamic threshold-2T0C(DT-2T0C) DRAM cell incorporating a ZnO charge-trap layer in the write transistor has been successfully achieved, addressing the negative hold voltage(V_(HOLD)) issue of conventional 2T0C DRAM cells using oxide channel layers. The proposed device facilitates dynamic modulation of turn-on voltage(V_(ON)) through an additional SET operation, allowing V_(ON) to shift above 0 V. The retention time in SET operation was extended to 10^(4) s by optimizing the tunneling layer deposition conditions. The device characterization revealed a significant correlation between V_(ON) and both the WRITE speed and the retention properties of the DT-2T0C, verifying the trade-off between WRITE time and retention time. A long retention time over 1000 s was achieved, even under VHOLD of 0 V.
文摘等离子体处理作为一种高效的表面改性技术,在二维纳米材料/碳基复合结构的形貌调控中具有独特优势。本文通过调控等离子体处理参数(例如气体氛围),研究其对二硫化钨/碳(WS2/C)复合结构表面形貌和缺陷分布的影响。结合扫描电子显微镜(Scanning Electron Microscope,SEM)和基于拉曼光谱的表征,揭示了等离子体处理诱导的WS2边缘选择性和碳纳米纤维骨架的协同效应,提高了复合材料的比表面积和边缘活性位点暴露程度。试验结果表明,参数优化后,等离子体处理可以有效调控WS2纳米晶片在碳纤维骨架中的分散性,并抑制晶片层间堆叠和层片团聚,从而增加边缘位置的暴露程度。该研究为高性能WS2/C复合材料的可控制备提供了新思路,推动其在能源存储与转换领域的实际应用。