- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Two-dimensional series connected photovoltaic cells defined by ferroelectric domains
摘要： Recently, a large amount of effort has been devoted to bringing p- and n-type two-dimensional (2D) materials in close contact to promise a p–n junction for photodetectors and photovoltaic devices. However, all solar cells based on 2D materials are single p–n junctions so far, where the open circuit voltage is usually limited by the bandgap of semiconductor materials. Here, by using a scanning-probe domain patterning method to polarize the ferroelectric ?lm, we demonstrate a series connected MoTe2 photovoltaic cell with an additive open circuit voltage and output electrical power. The nonvolatile MoTe2 p–n diodes exhibit a recti?cation ratio of 100. As a photodetector, the device presents a responsivity of 220 mA/W and an external quantum ef?ciency of 41% without any gate or bias voltages. The open circuit voltage increases linearly with the number of series connected p–n junctions and can be beyond the bandgap of the multilayer MoTe2.
关键词： photovoltaic cells,MoTe2,open circuit voltage,two-dimensional materials,ferroelectric domains
更新于2025-09-23 15:19:57
-
The Perfect Solar Cell
摘要： Within a few years only, methylammonium lead iodide (MAPbI3), and later more advanced organic metal halide perovskites, have performed an unprecedented rally towards highest power conversion efficiencies. A team of six scientists at Karlsruhe Institute of technology (KIt) has found evidence for ferroelectric domains in MAPbI3 thin-films. For their research, the team was awarded the Erwin-Schr?dinger-Prize of the helmholtz Association and the helmholtz Foundation.
关键词： Perovskite solar cells,Ferroelectric domains,MAPbI3,Photovoltaics,Energy conversion
更新于2025-09-12 10:27:22
-
Real-time observation of the temperature-induced phase transformation in GeTe and its thermal expansion properties
摘要： The GeTe-based system has long been considered as a promising candidate system for various functional applications; many of which are directly related to the polymorphic phase transformation in their crystalline forms. Consequently, the microstructure underlying their intriguing phase transition has been the subject of numerous studies. Here we provide real-time observation of the microstructural changes associated with the reversible pseudo-cubic (or rhombohedral) to cubic GeTe phase transition using high-voltage transmission electron microscopy (HV-TEM) operating at 1,250kV and complementary high-temperature X-ray diffraction (XRD). As a result of the phase transition, the pseudo-cubic GeTe domain’s configuration significantly changes from its original band-like to a spike-like morphology with a different orientation after a heating/cooling cycle. The coefficients of thermal expansion (CTE) properties as a function of temperature are also explored in relation to the GeTe phase transition.
关键词： CTE ellipsoids,in-situ high voltage transmission electron microscopy,GeTe,thermal expansion tensor,ferroelectric domains
更新于2025-09-10 09:29:36