ZnCo2O4/Si heterostructures have been fabricated by a pulsed laser deposition method, and their transport behaviors and photovoltaic properties have been characterized. The ZnCo2O4/Si heterostructures show a good rect...ZnCo2O4/Si heterostructures have been fabricated by a pulsed laser deposition method, and their transport behaviors and photovoltaic properties have been characterized. The ZnCo2O4/Si heterostructures show a good rectifying behavior at five different temperatures ranging from 50 K to 290 K. The measurements of the photovoltaic response reveals that a photovoltage of 33 mV is generated when the heterostructures are illuminated by a 532 nm laser of 250 mW/cm^2 and mechanically chopped at 2500 Hz. Both the photocurrent and the photovoltage clearly increase with the increase of the laser intensity at room temperature. However, the heterostructures' photovoltage peak decreases with the increase of the temperature. This work may open new perspectives for ZnCo2O4/Si heterostructure-based devices.展开更多
An epitaxial BiFeO_(3)/La_(0.7)Sr_(0.3)MnO_(3) (BFO/LSMO) multiferroic heterostructure is grown on an LaAlO_(3) (001) substrate by laser molecular beam epitaxy,and its photovoltaic properties are investigated.It is fo...An epitaxial BiFeO_(3)/La_(0.7)Sr_(0.3)MnO_(3) (BFO/LSMO) multiferroic heterostructure is grown on an LaAlO_(3) (001) substrate by laser molecular beam epitaxy,and its photovoltaic properties are investigated.It is found that the photocurrent is significantly increased under illumination,and the short-circuit photocurrent has a linear relationship with the laser intensity.Furthermore,when the ferroelectric polarization of the BFO layer is switched,the short-circuit photocurrent and open-circuit voltage can be switched.These results are discussed by considering the contributions from the ferroelectric polarization and the electrode/film interface.展开更多
Drying of colloidal droplets often develops versatile depositions.We study the drying deposition of both colloidal droplets containing silica nanoparticles and the silica colloidal droplets with polyethylene oxide(PEO...Drying of colloidal droplets often develops versatile depositions.We study the drying deposition of both colloidal droplets containing silica nanoparticles and the silica colloidal droplets with polyethylene oxide(PEO) additives.We focus on the effect of polymer additives on the deposition formation and the cracking dynamics by using in-situ microscope observation.With PEO additives,a transition from ring-like deposition to uniform deposition is observed,and the cracking dynamics is greatly reduced.The PEO additives enhance the adsorption of particles at the air-water interface,thus forming the network structure at the interface which blocks the outward capillary flow.This contributes to the uniform deposition.Meanwhile,the multi-distribution of the aggregates size enhances the non-homogeneity of the drying film and consequently results in multi-nucleation of cracks.This reduces the stress accumulation that drives the crack propagation and may be responsible for the sluggish cracking dynamics.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61078057)the Natural Science Foundation of Shannxi Province,China(Grant No.2011GM6013)+1 种基金the Northwestern Polytechnical University Foundation for Fundamental Research,China(Grant Nos.JC20110270 and JC201271)the Open Project of Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education,Lanzhou University,China(Grant No.LZUMMM2013001)
文摘ZnCo2O4/Si heterostructures have been fabricated by a pulsed laser deposition method, and their transport behaviors and photovoltaic properties have been characterized. The ZnCo2O4/Si heterostructures show a good rectifying behavior at five different temperatures ranging from 50 K to 290 K. The measurements of the photovoltaic response reveals that a photovoltage of 33 mV is generated when the heterostructures are illuminated by a 532 nm laser of 250 mW/cm^2 and mechanically chopped at 2500 Hz. Both the photocurrent and the photovoltage clearly increase with the increase of the laser intensity at room temperature. However, the heterostructures' photovoltage peak decreases with the increase of the temperature. This work may open new perspectives for ZnCo2O4/Si heterostructure-based devices.
基金Supported by the National Basic Research Program of China under Grant No 2012CB921900the National Natural Science Foundation of China under Grant Nos 61377035 and 11404264the Fundamental Research Funds for the Central Universities under Grant No 3102014JCQ01085
基金Supported by the National Natural Science Foundation of China under Grant No 61078057the NPU Foundation for Fundamental Research under Grant Nos JC201048 and JC20110273.
文摘An epitaxial BiFeO_(3)/La_(0.7)Sr_(0.3)MnO_(3) (BFO/LSMO) multiferroic heterostructure is grown on an LaAlO_(3) (001) substrate by laser molecular beam epitaxy,and its photovoltaic properties are investigated.It is found that the photocurrent is significantly increased under illumination,and the short-circuit photocurrent has a linear relationship with the laser intensity.Furthermore,when the ferroelectric polarization of the BFO layer is switched,the short-circuit photocurrent and open-circuit voltage can be switched.These results are discussed by considering the contributions from the ferroelectric polarization and the electrode/film interface.
基金supported by the National Natural Science Foundation of China (Grant No.51103117)Shaanxi Provincial Natural Science Foundation (Grant No.2012JQ1016)+2 种基金NPU Foundation for Fundamental Research (Grant Nos.JCY20130147 and JC201125)Specialized Research Fund for the Doctoral Program of Higher Education (Grant No.20126102120058)the Research Fund of the State Key Laboratory of Solidification Processing in NWPU (Grant No.SKLSP201217)
文摘Drying of colloidal droplets often develops versatile depositions.We study the drying deposition of both colloidal droplets containing silica nanoparticles and the silica colloidal droplets with polyethylene oxide(PEO) additives.We focus on the effect of polymer additives on the deposition formation and the cracking dynamics by using in-situ microscope observation.With PEO additives,a transition from ring-like deposition to uniform deposition is observed,and the cracking dynamics is greatly reduced.The PEO additives enhance the adsorption of particles at the air-water interface,thus forming the network structure at the interface which blocks the outward capillary flow.This contributes to the uniform deposition.Meanwhile,the multi-distribution of the aggregates size enhances the non-homogeneity of the drying film and consequently results in multi-nucleation of cracks.This reduces the stress accumulation that drives the crack propagation and may be responsible for the sluggish cracking dynamics.