Nano-structured photon management is currently an interesting topic since it can enhance the optical absorption and reduce the surface reflection which will improve the performance of many kinds of optoelectronic devi...Nano-structured photon management is currently an interesting topic since it can enhance the optical absorption and reduce the surface reflection which will improve the performance of many kinds of optoelectronic devices, such as Si-based solar cells and light emitting diodes. Here, we report the fabrication of periodically nano-patterned Si structures by using polystyrene nano-sphere lithography technique. By changing the diameter of nano-spheres and the dry etching parameters, such as etching time and etching power, the morphologies of formed Si nano-structures can be well controlled as revealed by atomic force microscopy.A good broadband antireflection property has been achieved for the formed periodically nano-patterned Si structures though they have the low aspect ratio(<0.53). The reflection can be significantly reduced compared with that of flat Si substrate in a wavelength range from 400 nm to 1200 nm. The weighted mean reflection under the AM1.5 solar spectrum irradiation can be as low as 3.92% and the corresponding optical absorption is significantly improved, which indicates that the present Si periodic nano-structures can be used in Si-based thin film solar cells.展开更多
In this paper,we present our efforts on simulating and analyzing the effect of two-dimensional nano-sphere surface array on the characteristic of GaAs solar cells.Based on the scattering and diffraction theory of the ...In this paper,we present our efforts on simulating and analyzing the effect of two-dimensional nano-sphere surface array on the characteristic of GaAs solar cells.Based on the scattering and diffraction theory of the photonic crystals,the simulation results show that the distance of adjacent nano-spheres(D)has the pronounced influence on the conversion efficiency and exhibits much poor tolerance,the absolutely conversion efficiency is reduced by exceeding of 2%as the D varies from 0 to 1μm,in addition,the lower conversion efficiency(<18%)is exhibited and almost remains unaltered when the D is of>2μm.The radius(R)of nano-spheres demonstrates much great tolerance.For D=0,the solar cells exhibit high conversion efficiency(>20%)and the efficiency is only varied by less than 1%when R is varied in a very wide region of 0.3-1.2μm.One can also find out that there is good tolerance for efficiency around the optimal value of refractive index and there is only about 0.2%decrease in final cell efficiency for around±24%variation in the optimal values,which implys that it does not demand high precision processing equipment and the whole nano-sphere array could be fully complemented using self-assembled chemical methods.展开更多
In this work, electrospray technique combined sol-gel method was used to prepare porous TiO2 film. X-ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM) analyses were ...In this work, electrospray technique combined sol-gel method was used to prepare porous TiO2 film. X-ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM) analyses were conducted to examine the chemical composition, phase structure, and surface morphology of the sprayed TiO2 film. After calcined at 450℃ in air atmosphere for 2 h, mesoporous TiO2 nano-spheres clusters were formed on the surface of silicon wafer and the average size of nano-spheres was 250 nm. Ti presented as Ti 4+ oxidation state in TiO2 film, and the TiO2 film exhibited the anatase phase. The sprayed porous TiO2 films were employed as photocatalyst to degrade organic phosphorus in water samples. Compared with the TiO2 film prepared by Sol-Gel spin-coating method, the porous TiO2 film deposited by electrospray combined sol-gel method showed higher photocatalytic activity.展开更多
The intensive development of micro-/nanotechnologies offers a new route to construct sophisticated architectures of emerging soft electronics.Among the many classes of stretchable materials,micro-/nanostructured poly(...The intensive development of micro-/nanotechnologies offers a new route to construct sophisticated architectures of emerging soft electronics.Among the many classes of stretchable materials,micro-/nanostructured poly(dimethylsiloxane)(PDMS)has emerged as a vital building block based on its merits of flexibility,stretchability,simple processing,and,more importantly,high degrees of freedom of incorporation with other functional materials,including metals and semiconductors.The artificially designed geometries play important roles in achieving the desired mechanical and electrical performances of devices and thus show great potential for applications in the fields of stretchable displays,sensors and actuators as well as in health-monitoring device platforms.Meanwhile,novel lithographic methods to produce stretchable platforms with superb reliability have recently attracted research interest.The aim of this review is to comprehensively summarize the progress regarding micro-/nanostructured PDMS and their promising soft electronic applications.This review is concluded with a brief outlook and further research directions.展开更多
基金supported by NSFC(Nos.61036001and 11274155)"973"pro ject(2013CB632101)NSF of Jiangsu Province(BK2010010)and PAPD
文摘Nano-structured photon management is currently an interesting topic since it can enhance the optical absorption and reduce the surface reflection which will improve the performance of many kinds of optoelectronic devices, such as Si-based solar cells and light emitting diodes. Here, we report the fabrication of periodically nano-patterned Si structures by using polystyrene nano-sphere lithography technique. By changing the diameter of nano-spheres and the dry etching parameters, such as etching time and etching power, the morphologies of formed Si nano-structures can be well controlled as revealed by atomic force microscopy.A good broadband antireflection property has been achieved for the formed periodically nano-patterned Si structures though they have the low aspect ratio(<0.53). The reflection can be significantly reduced compared with that of flat Si substrate in a wavelength range from 400 nm to 1200 nm. The weighted mean reflection under the AM1.5 solar spectrum irradiation can be as low as 3.92% and the corresponding optical absorption is significantly improved, which indicates that the present Si periodic nano-structures can be used in Si-based thin film solar cells.
基金National Nature Science Foundation of China(Grant No.61871350)Zhejiang Provincial Department of Education for their financial support of this research(Grant Nos.Y201121882 and Y201225406)
文摘In this paper,we present our efforts on simulating and analyzing the effect of two-dimensional nano-sphere surface array on the characteristic of GaAs solar cells.Based on the scattering and diffraction theory of the photonic crystals,the simulation results show that the distance of adjacent nano-spheres(D)has the pronounced influence on the conversion efficiency and exhibits much poor tolerance,the absolutely conversion efficiency is reduced by exceeding of 2%as the D varies from 0 to 1μm,in addition,the lower conversion efficiency(<18%)is exhibited and almost remains unaltered when the D is of>2μm.The radius(R)of nano-spheres demonstrates much great tolerance.For D=0,the solar cells exhibit high conversion efficiency(>20%)and the efficiency is only varied by less than 1%when R is varied in a very wide region of 0.3-1.2μm.One can also find out that there is good tolerance for efficiency around the optimal value of refractive index and there is only about 0.2%decrease in final cell efficiency for around±24%variation in the optimal values,which implys that it does not demand high precision processing equipment and the whole nano-sphere array could be fully complemented using self-assembled chemical methods.
基金Supported by the National Basic Research Program of China (No. 2009CB320300)National Natural Science Foundation of China (No. 61072023)National High Technology Research and Development Programs (No.2012AA040506, No. 2012AA101608)
文摘In this work, electrospray technique combined sol-gel method was used to prepare porous TiO2 film. X-ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM) analyses were conducted to examine the chemical composition, phase structure, and surface morphology of the sprayed TiO2 film. After calcined at 450℃ in air atmosphere for 2 h, mesoporous TiO2 nano-spheres clusters were formed on the surface of silicon wafer and the average size of nano-spheres was 250 nm. Ti presented as Ti 4+ oxidation state in TiO2 film, and the TiO2 film exhibited the anatase phase. The sprayed porous TiO2 films were employed as photocatalyst to degrade organic phosphorus in water samples. Compared with the TiO2 film prepared by Sol-Gel spin-coating method, the porous TiO2 film deposited by electrospray combined sol-gel method showed higher photocatalytic activity.
基金supported by the National Research Foundation (NRF) of Korea funded by the Ministry of Science and ICT and Future Planning (MSIP) (2016R1E1A1A01943131)
文摘The intensive development of micro-/nanotechnologies offers a new route to construct sophisticated architectures of emerging soft electronics.Among the many classes of stretchable materials,micro-/nanostructured poly(dimethylsiloxane)(PDMS)has emerged as a vital building block based on its merits of flexibility,stretchability,simple processing,and,more importantly,high degrees of freedom of incorporation with other functional materials,including metals and semiconductors.The artificially designed geometries play important roles in achieving the desired mechanical and electrical performances of devices and thus show great potential for applications in the fields of stretchable displays,sensors and actuators as well as in health-monitoring device platforms.Meanwhile,novel lithographic methods to produce stretchable platforms with superb reliability have recently attracted research interest.The aim of this review is to comprehensively summarize the progress regarding micro-/nanostructured PDMS and their promising soft electronic applications.This review is concluded with a brief outlook and further research directions.
