Pub Date : 2010-12-01DOI: 10.1109/ESCINANO.2010.5701014
A. A. Hamzah, J. Yunas, Dee Chang Fu, B. Yeop Majlis
Many biological fluids require filtration during its processing, either to separate the various components in the fluid or to remove unwanted or harmful contaminants from the medium. Challenges arise in the filtration process as the masses to be filtered appear in various sizes [1]. Conventional filtration method requires lengthy and timely repeated processes. A simple solution to this problem is the isolation of the unwanted masses via sequenced filtration using precisely sized nanoporous silicon membrane.
{"title":"Electrochemically etched nanoporous silicon membrane for filtration of biological fluids","authors":"A. A. Hamzah, J. Yunas, Dee Chang Fu, B. Yeop Majlis","doi":"10.1109/ESCINANO.2010.5701014","DOIUrl":"https://doi.org/10.1109/ESCINANO.2010.5701014","url":null,"abstract":"Many biological fluids require filtration during its processing, either to separate the various components in the fluid or to remove unwanted or harmful contaminants from the medium. Challenges arise in the filtration process as the masses to be filtered appear in various sizes [1]. Conventional filtration method requires lengthy and timely repeated processes. A simple solution to this problem is the isolation of the unwanted masses via sequenced filtration using precisely sized nanoporous silicon membrane.","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"13 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74525679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/ESCINANO.2010.5701005
S. S. Shariffudin, M. Ibrahim, Z. Zulkifli, A. S. Hamzah, M. Rusop
Recently, the performance of optoelectronics devices such as organic light emitting diodes and organic solar cells has been enhanced by the incorporation of inorganic semiconductors to form hybrid organic-inorganic. This approach can take advantages of the beneficial properties of both materials: superior optoelectronic properties of conjugated organic polymers and high electron mobility of inorganic semiconductors [1]. The objective of this paper is to study the effect of different weight percentage of ZnO nanoparticles on the optical properties of the nanocomposite MEH-PPV:ZnO thin films. The samples were prepared using sol-gel spin coating method on glass substrates. Current-voltage properties of the thin films were investigated. Conductivity of the thin films is plotted and shown in Fig.1. The conductivity of the samples increases with the increment of the ZnO nanoparticles except for sample with 10wt% of the ZnO in the nanocomposite thin films.
{"title":"The optical properties of nanocomposite MEH-PPV:ZnO thin films","authors":"S. S. Shariffudin, M. Ibrahim, Z. Zulkifli, A. S. Hamzah, M. Rusop","doi":"10.1109/ESCINANO.2010.5701005","DOIUrl":"https://doi.org/10.1109/ESCINANO.2010.5701005","url":null,"abstract":"Recently, the performance of optoelectronics devices such as organic light emitting diodes and organic solar cells has been enhanced by the incorporation of inorganic semiconductors to form hybrid organic-inorganic. This approach can take advantages of the beneficial properties of both materials: superior optoelectronic properties of conjugated organic polymers and high electron mobility of inorganic semiconductors [1]. The objective of this paper is to study the effect of different weight percentage of ZnO nanoparticles on the optical properties of the nanocomposite MEH-PPV:ZnO thin films. The samples were prepared using sol-gel spin coating method on glass substrates. Current-voltage properties of the thin films were investigated. Conductivity of the thin films is plotted and shown in Fig.1. The conductivity of the samples increases with the increment of the ZnO nanoparticles except for sample with 10wt% of the ZnO in the nanocomposite thin films.","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"36 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74061175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Possibility of modeling and simulation of single electron devices, such as Single electron box (SEB), in a circuit simulator such as SPICE is a key step to designing integrated circuits based on single electron devices, because it makes possible analyzing of a combination of SEB and other circuit elements in a single platform. Some efforts have been done to this end in the past and some models introduced [1,2,3] but all of the models were restricted to low frequency and low temperature range. In this paper, we propose a circuit model for SEB that can operate in high temperature and also in the intrinsic frequency range of these devices. This model can be used for an estimation of the bit error rate in logic applications of these devices as well.
{"title":"A time-dependent SPICE model for single electron box and its application to logic gates at low and high temperatures","authors":"Farzad Ahmadi Gooraji, M. Sharifi, D. Bahrepour","doi":"10.1063/1.3586974","DOIUrl":"https://doi.org/10.1063/1.3586974","url":null,"abstract":"Possibility of modeling and simulation of single electron devices, such as Single electron box (SEB), in a circuit simulator such as SPICE is a key step to designing integrated circuits based on single electron devices, because it makes possible analyzing of a combination of SEB and other circuit elements in a single platform. Some efforts have been done to this end in the past and some models introduced [1,2,3] but all of the models were restricted to low frequency and low temperature range. In this paper, we propose a circuit model for SEB that can operate in high temperature and also in the intrinsic frequency range of these devices. This model can be used for an estimation of the bit error rate in logic applications of these devices as well.","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"11 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74283227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/ESCINANO.2010.5700936
S. Chin, K. Swaminatha Iyer, C. Raston
Superparamagnetic magnetite (Fe3O4) nanoparticles have been widely studied for various scientific and technological applications such as magnetic storage media, contrast agents for magnetic resonance imaging (MRI), biolabelling and separation of biomolecules, and magnetic targetted drug delivery. In the absence of surface coating, Fe3O4 nanoparticles tend to aggregate due to the Van der Waals forces coupled with the magnetic dipole-dipole attractions between the particles. In order to successfully prepare stable magnetite dispersions, any attractive forces between the nanoparticles must be overcome. In this study, magnetite nanoparticles have been prepared by chemical precipitation method. Gold (Au) and silver (Ag) are ideal coating for Fe3O4 nanoparticles due to their high chemical stability, biocompatibility, and their affinity for binding to amine/thiol terminal groups of organic molecules. In addition these coatings also render the Fe3O4 nanoparticles with plasmonic properties.
{"title":"Superparamagnetic core-shell nanoparticles for biomedical applications","authors":"S. Chin, K. Swaminatha Iyer, C. Raston","doi":"10.1109/ESCINANO.2010.5700936","DOIUrl":"https://doi.org/10.1109/ESCINANO.2010.5700936","url":null,"abstract":"Superparamagnetic magnetite (Fe3O4) nanoparticles have been widely studied for various scientific and technological applications such as magnetic storage media, contrast agents for magnetic resonance imaging (MRI), biolabelling and separation of biomolecules, and magnetic targetted drug delivery. In the absence of surface coating, Fe3O4 nanoparticles tend to aggregate due to the Van der Waals forces coupled with the magnetic dipole-dipole attractions between the particles. In order to successfully prepare stable magnetite dispersions, any attractive forces between the nanoparticles must be overcome. In this study, magnetite nanoparticles have been prepared by chemical precipitation method. Gold (Au) and silver (Ag) are ideal coating for Fe3O4 nanoparticles due to their high chemical stability, biocompatibility, and their affinity for binding to amine/thiol terminal groups of organic molecules. In addition these coatings also render the Fe3O4 nanoparticles with plasmonic properties.","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"168 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72738737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/ESCINANO.2010.5701054
Lee Wai Yee, T. K. Sin, Soong Wai Mun, R. M. Saman
Carbon nanotubes (CNT) has attracted much attention in recent years due to its unique properties and vast potential in nanotechnology. Over the years, extensive research has been conducted to develop a reliable synthesis methodology to produce CNT. Among many methods for CNT growth, transition metal based catalyst via plasma enhanced chemical vapour deposition (PECVD) is one of the widely adaptable methods for large scale CNT growth.
{"title":"Morphology and particle size analysis on Al/Ni binary catalyst for carbon nanotube growth through plasma enhanced chemical vapour deposition","authors":"Lee Wai Yee, T. K. Sin, Soong Wai Mun, R. M. Saman","doi":"10.1109/ESCINANO.2010.5701054","DOIUrl":"https://doi.org/10.1109/ESCINANO.2010.5701054","url":null,"abstract":"Carbon nanotubes (CNT) has attracted much attention in recent years due to its unique properties and vast potential in nanotechnology. Over the years, extensive research has been conducted to develop a reliable synthesis methodology to produce CNT. Among many methods for CNT growth, transition metal based catalyst via plasma enhanced chemical vapour deposition (PECVD) is one of the widely adaptable methods for large scale CNT growth.","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"105 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78609998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/ESCINANO.2010.5700990
N. A. Abdul Manaf, M. Alias, S. Mitani, F. Maskuriy
A comprehensive study has been done to investigate the lasing characteristic of 1.3 µm GaInNAs quantum well (QW) lasers. We have varied the Nitrogen (N) compositions in GaInNAs QW with N=1.0≤x≤2.0. Significant improvement of lasing wavelength, emission efficiency and output power were demonstrated with higher N compositions. The emissions wavelength red shifted linearly when the N compositions enlarge. As formerly known, the band gap of GaInNAs is controlled by adjusting the ratio of group III (Ga, In) or group V (N, As) materials. As the N increased, the band gap will reduce and the emission wavelength increased.The average ratio of the red-shifted is 92.49 nm per N percentage. The PL intensity seems to reduce with higher N which due to the deteriorates crystal quality at higher N incorporation. We believed that that the optical quality of the GaInNAs QW depends on N compositions and total number of N incorporated in the QW. The strain profile between QW and the surrounding matrix has a major effect on the optical quality of GaInNAs QW. However the structural qualities such as homogeneity, strain fluctuation and interface roughness will degrade with too much N composition, hence reduce the threshold current, and increased the external differential quantum efficiency. Further comparisons on the devices performance will be report further.
本文对1.3µm GaInNAs量子阱激光器的激光特性进行了全面的研究。我们在N=1.0≤x≤2.0的GaInNAs QW中改变了氮(N)组成。高N含量可显著提高激光波长、发射效率和输出功率。随着N组分的增大,发射波长呈线性红移。如前所述,GaInNAs的带隙是通过调节III族(Ga, In)或V族(N, As)材料的比例来控制的。随着N的增大,带隙减小,发射波长增大。红移比平均为92.49 nm / N %。随着N的增加,发光强度降低,这是由于高N掺入导致晶体质量恶化。我们认为,GaInNAs量子阱的光学质量取决于N的组成和量子阱中N的总数。量子阱与周围基体之间的应变分布对GaInNAs量子阱的光学质量有重要影响。然而,过多的N元素会导致均匀性、应变波动和界面粗糙度等结构品质下降,从而降低阈值电流,增加外部微分量子效率。对设备性能的进一步比较将进一步报告。
{"title":"Impact of Nitrogen on the lasing characteristic of 1.3 µm GaInNAs quantum well lasers","authors":"N. A. Abdul Manaf, M. Alias, S. Mitani, F. Maskuriy","doi":"10.1109/ESCINANO.2010.5700990","DOIUrl":"https://doi.org/10.1109/ESCINANO.2010.5700990","url":null,"abstract":"A comprehensive study has been done to investigate the lasing characteristic of 1.3 µm GaInNAs quantum well (QW) lasers. We have varied the Nitrogen (N) compositions in GaInNAs QW with N=1.0≤x≤2.0. Significant improvement of lasing wavelength, emission efficiency and output power were demonstrated with higher N compositions. The emissions wavelength red shifted linearly when the N compositions enlarge. As formerly known, the band gap of GaInNAs is controlled by adjusting the ratio of group III (Ga, In) or group V (N, As) materials. As the N increased, the band gap will reduce and the emission wavelength increased.The average ratio of the red-shifted is 92.49 nm per N percentage. The PL intensity seems to reduce with higher N which due to the deteriorates crystal quality at higher N incorporation. We believed that that the optical quality of the GaInNAs QW depends on N compositions and total number of N incorporated in the QW. The strain profile between QW and the surrounding matrix has a major effect on the optical quality of GaInNAs QW. However the structural qualities such as homogeneity, strain fluctuation and interface roughness will degrade with too much N composition, hence reduce the threshold current, and increased the external differential quantum efficiency. Further comparisons on the devices performance will be report further.","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"148 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77855572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/ESCINANO.2010.5700939
N. Nayan
RF magnetron sputtering is a well known technique to fabricate metal and metal oxide thin film. Basically, metal oxide thin film was achieved using the combination of inert gas and reactive gas during the sputtering deposition. Recently, the fabrication of zinc oxide (ZnO) thin film has been investigated intensively in the global scale as well as in Malaysia [1]. Zinc oxide (ZnO) is a material of great interest for short-wavelength light-emitting electro-optical nanodevices due to its wide band gap (3.37 eV) and large excitation binding energy (60 meV). Their applications is in many fields such as optoelectronics, transparent conductive oxide, solar cell and photovoltaic, sensors and etc‥ Various methods has been used to obtain and improve ZnO thin film such as sputtering, chemical bath deposition, pulsed laser deposition and chemical vapor deposition [2,3].
{"title":"Optimization of RF magnetron sputtering plasma using Zn target","authors":"N. Nayan","doi":"10.1109/ESCINANO.2010.5700939","DOIUrl":"https://doi.org/10.1109/ESCINANO.2010.5700939","url":null,"abstract":"RF magnetron sputtering is a well known technique to fabricate metal and metal oxide thin film. Basically, metal oxide thin film was achieved using the combination of inert gas and reactive gas during the sputtering deposition. Recently, the fabrication of zinc oxide (ZnO) thin film has been investigated intensively in the global scale as well as in Malaysia [1]. Zinc oxide (ZnO) is a material of great interest for short-wavelength light-emitting electro-optical nanodevices due to its wide band gap (3.37 eV) and large excitation binding energy (60 meV). Their applications is in many fields such as optoelectronics, transparent conductive oxide, solar cell and photovoltaic, sensors and etc‥ Various methods has been used to obtain and improve ZnO thin film such as sputtering, chemical bath deposition, pulsed laser deposition and chemical vapor deposition [2,3].","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"32 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80493588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A 3.1–10.6GHz ultra-wideband low noise-amplifier (UWB LNA) using standard 0.18um CMOS technology has been reported. A two-stage, common-gate in cascade with cascode, UWB LNA has been proposed to achieve more than 10dB input and output return loss, high gain of 26dB, and NF of 2.9dB over the full frequency band. The proposed LNA consumes 10mW from 1.8V supply. The designed LNA has an excellent high gain in comparison with previous works.
{"title":"0.18um 3.1–10.6GHz CMOS UWB LNA with 25 ±1dB gain","authors":"S. Shamsadini, F. Kashani, Neda Bathaei","doi":"10.1063/1.3586977","DOIUrl":"https://doi.org/10.1063/1.3586977","url":null,"abstract":"A 3.1–10.6GHz ultra-wideband low noise-amplifier (UWB LNA) using standard 0.18um CMOS technology has been reported. A two-stage, common-gate in cascade with cascode, UWB LNA has been proposed to achieve more than 10dB input and output return loss, high gain of 26dB, and NF of 2.9dB over the full frequency band. The proposed LNA consumes 10mW from 1.8V supply. The designed LNA has an excellent high gain in comparison with previous works.","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"33 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85454029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/ESCINANO.2010.5700960
I. Senain, N. Nayan, H. Saim
Dye-sensitized solar cell (DSSC) is one of the most promising one for environmental and sustainable energy technologies. One of the key factors that affect the performance of DSSCs is the metal oxide layer. In the present research, we focus on the titanium dioxide (TiO2) thin film, as it has been used as a transparent metal oxide for DSSC's application. However, the optimization of several factors which include the preparation technique of nanostructure thin film, high surface area and transparent of TiO2 film electrodes are essential [1]. It is very important to study the evolution of different physical and chemical properties of TiO2 which is effective for controlled modification. Recently, polyethylene glycol (PEG) has been widely used as a template to modify the structure and surface morphology of the TiO2 thin film [2].
{"title":"Effect of polyethylene glycol on structural and electrical properties of TiO2 thin film derived from SOL-GEL technique","authors":"I. Senain, N. Nayan, H. Saim","doi":"10.1109/ESCINANO.2010.5700960","DOIUrl":"https://doi.org/10.1109/ESCINANO.2010.5700960","url":null,"abstract":"Dye-sensitized solar cell (DSSC) is one of the most promising one for environmental and sustainable energy technologies. One of the key factors that affect the performance of DSSCs is the metal oxide layer. In the present research, we focus on the titanium dioxide (TiO2) thin film, as it has been used as a transparent metal oxide for DSSC's application. However, the optimization of several factors which include the preparation technique of nanostructure thin film, high surface area and transparent of TiO2 film electrodes are essential [1]. It is very important to study the evolution of different physical and chemical properties of TiO2 which is effective for controlled modification. Recently, polyethylene glycol (PEG) has been widely used as a template to modify the structure and surface morphology of the TiO2 thin film [2].","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"14 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76012455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/ESCINANO.2010.5701098
B. Ohtani
For chemical reactions occurring on the surfaces, e.g., catalysis and photocatalysis, design and fabrication of structures in two different scales, i.e., angstrom/nanometer and micrometer ranges. The former regulates the adsorption and surface reaction of molecules, while the latter gives influence on the diffusion and mechanical strength of the material. In order to control the structures in both scale regions, use of hierarchical and/or anisotropic structure is beneficial. In this lecture, the author presents several examples of particles with hierarchical and/or anisotropic structures. First example is hollow core-shell (HCS) particles with a cadmium sulfide (CdS) nanoparticles core and nanoporous silica shell which drive efficient photocatalytic reaction without any coagulation of CdS nanoparticles. Similar HCS structured particles with a titania core and a silica shell were found to oxidize small organic compounds selectively under photoirradiation in the presence of oxygen. Third example is phase-boundary (PB) catalytic particles; zeolite or silica particles with hydrophilic and hydrophobic surface domains were prepared by newly developed methodology. The PB particles are spontaneously assembled at interface between aqueous and organic phases and thereby catalyze reaction of water-immiscible organic substrates with reagents dissolved in water, i.e., epoxidation of olefins with hydrogen peroxide without agitation or use of co-solvent. Flake-ball particles, assembly of nanometersized platelets, of bismuth tungstate (Bi2WO6), showed high-level of photocatalytic activities for both liquid and gas phase reactions under visible-light irradiation, presumably due to their high-crystallinity of platelets and relatively large surface area.
{"title":"Nano and microstructured materials with chemical functions: Anisotropic particles for catalysis and photo-catalysis","authors":"B. Ohtani","doi":"10.1109/ESCINANO.2010.5701098","DOIUrl":"https://doi.org/10.1109/ESCINANO.2010.5701098","url":null,"abstract":"For chemical reactions occurring on the surfaces, e.g., catalysis and photocatalysis, design and fabrication of structures in two different scales, i.e., angstrom/nanometer and micrometer ranges. The former regulates the adsorption and surface reaction of molecules, while the latter gives influence on the diffusion and mechanical strength of the material. In order to control the structures in both scale regions, use of hierarchical and/or anisotropic structure is beneficial. In this lecture, the author presents several examples of particles with hierarchical and/or anisotropic structures. First example is hollow core-shell (HCS) particles with a cadmium sulfide (CdS) nanoparticles core and nanoporous silica shell which drive efficient photocatalytic reaction without any coagulation of CdS nanoparticles. Similar HCS structured particles with a titania core and a silica shell were found to oxidize small organic compounds selectively under photoirradiation in the presence of oxygen. Third example is phase-boundary (PB) catalytic particles; zeolite or silica particles with hydrophilic and hydrophobic surface domains were prepared by newly developed methodology. The PB particles are spontaneously assembled at interface between aqueous and organic phases and thereby catalyze reaction of water-immiscible organic substrates with reagents dissolved in water, i.e., epoxidation of olefins with hydrogen peroxide without agitation or use of co-solvent. Flake-ball particles, assembly of nanometersized platelets, of bismuth tungstate (Bi2WO6), showed high-level of photocatalytic activities for both liquid and gas phase reactions under visible-light irradiation, presumably due to their high-crystallinity of platelets and relatively large surface area.","PeriodicalId":6354,"journal":{"name":"2010 International Conference on Enabling Science and Nanotechnology (ESciNano)","volume":"40 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80544297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}