Chung-Kwei Lin - Profile on Academia.edu (original) (raw)
Papers by Chung-Kwei Lin
Gas sensors with porous three-dimensional framework using TiO2/polymer double-shell hollow microsphere
Thin Solid Films, 2011
The correlations between the structures and gas-sensing properties of porous thin-film gas sensor... more The correlations between the structures and gas-sensing properties of porous thin-film gas sensors made of packed hollow spheres are investigated. For this purpose, hollow polymeric spheres were used as templates. Double-shell hollow spheres were prepared by encapsulating the polymeric hollow spheres with TiO2 shells. Solid polymeric spheres were used as templates for comparison. Porous thin-film gas sensor with interconnected three-dimensional pores was prepared by using the TiO2 encapsulated hollow spheres. The double-shell hollow spheres and porous titania films were characterized by XRD, BET, TEM and SEM. The gas-sensing properties of the sensors toward NO2 depend on the type of template and the three-dimensional porous structure of the films. Using the hollow sphere template and adding precursors during the film formation procedure help to prevent the collapse of hollow sphere and form the mesopores in films after removing the template. These films show enhanced gas sensitivity when compared to TiO2 polycrystalline films. Such improvement in sensitivity results from the porous architecture of the hollow microsphere films which not only increase the active surface area but also promotes the gas diffusion.
X-ray irradiation synthesis of PEG-coated Au-Pd nanoparticles
Nanotechnology, Jan 4, 2015
We demonstrate that the combination of x-ray irradiation and capping by polyethylene glycol (PEG)... more We demonstrate that the combination of x-ray irradiation and capping by polyethylene glycol (PEG) produces excellent flexibility in controlling the structure of Au-Pd nanoparticles while preserving their catalytic performance. We specifically adopted two different fabrication methods: co-reduction and seed-assisted reduction. In both cases, precursor composition plays an important role in controlling the phases and size of the bimetallic nanoparticles. The optimal catalytic performance is obtained with the highest Pd concentration and when the nanoparticles consist of a Au core and a Pd shell.
Uncapped Au-Pd colloidal nanoparticles show catalysis enhancement
RSC Adv., 2015
ABSTRACT The catalytic properties of Pd trigger a strong interest on the related catalysis by Au-... more ABSTRACT The catalytic properties of Pd trigger a strong interest on the related catalysis by Au-Pd nanoparticles. However, the analysis of such phenomena was complicated so far by the presence of capping. Using x-ray irradiation, we could produce uncapped Au-Pd nanoparticles and study their catalytic features, finding in particular their relation to the Pd content. Furthermore, the fabrication process is per se interesting, yielding excellent and flexibly controllable nanoparticles with a rather simple procedure.
Characterization and Modification of Nanocrystalline Iron Oxide Powders Prepared by an Inert Gas Condensation Technique
Materials Science Forum, 2007
A study on the corrosion and erosion behavior of electroless nickel and TiAlN/ZrN duplex coatings on ductile iron
Applied Surface Science
This study utilized electroless nickel (EN) and cathodic arc evaporation (CAE) technologies to de... more This study utilized electroless nickel (EN) and cathodic arc evaporation (CAE) technologies to deposit protective coatings onto ductile iron. Polarization corrosion tests were performed in 3.5 wt.% sodium chloride, and also erosion tests were carried out by using Al2O3 particles (∼177 μm in size and Mohr 7 scale) of about 5 g. Surface morphologies of the corroded and eroded specimens were observed separately. To further understand the coating effects on both the corrosive and erosive behavior of ductile iron, coating structure, morphology, and adhesion were analyzed using X-ray diffractormeter, scanning electron microscopy, and Rockwell-C indenter, respectively. The results showed that the EN exhibited an amorphous structure while the CAE-TiAlN/ZrN coating was a multilayered nanocrystalline. When the TiAlN/ZrN coated specimen with EN interlayer could effectively increase the adhesion strength between the CAE coating and substrate. Consequently, the combination of TiAlN/ZrN and EN de...
Influence of Fe3O4 Nanoparticles on Pseudocapacitive Behavior of the Charge Storage Process
Journal of Alloys and Compounds, 2015
ABSTRACT
Preparation and characterization of nanocrystalline Nb3Al alloy
Thin Solid Films, 2011
In this study, tungsten oxide films were prepared by sol-gel technique. Various amounts of multiw... more In this study, tungsten oxide films were prepared by sol-gel technique. Various amounts of multiwalled carbon nanotubes (MWCNTs) were added during sol-gel process to obtain hybrid WO 3 /MWCNT films. The original and hybrid films were characterized by thermogravimetric analysis, X-ray diffraction analysis, and scanning electron microscopy analysis, whereas the electrochromic performance was evaluated by measuring changes in the optical transmittance caused by potentiostatic charge-discharge intercalation. The influence on the structure and properties of tungsten oxide film due to MWCNT addition was also investigated. The results showed that all of the films were amorphous and exhibited porous microstructure. The electrochromic performance of pristine WO 3 film was improved by adding MWCNTs that served as a template for the growth of WO 3 and resulted in more porous microstructure. The hybrid tungsten oxide films with 0.1 wt.% MWCNT addition exhibited the best electrochromic performance.
Glass Forming Ability in Amorphous Ti50Cu35-xNi15Snx Alloys Prepared by Mechanical Alloying
Materials Science Forum, 2005
Nanostructured Materials, 1998
nanocrystalline Ag-Fe solidsolutions increase with increasing atomic percentage of iron. 01998 Ac... more nanocrystalline Ag-Fe solidsolutions increase with increasing atomic percentage of iron. 01998 Acta Metallurgica Inc.
Preparation of Mg-Y-Cu Bulk Metallic Glass by High Energy Ball Milling
Journal of Metastable and Nanocrystalline Materials, 2005
Characterization of iron nitride powders formed by mechanical alloying and atmospheric heat treatment techniques
Journal of the Chinese Institute of Engineers, 2001
... the same trend as the one found in several alloy systems, such as Ni-Nb (Lee and Koch, 1987) ... more ... the same trend as the one found in several alloy systems, such as Ni-Nb (Lee and Koch, 1987) and Co-Ta (Pee-Yew Lee and Ju ... Jack (1994) has reported the transient appearance of the α′′-Fe16N2 phase by aging a supersaturated Fe solid solution at 250°C. Different phase ...
Preparation of iron nitride powders through mechanical alloying and atmospheric heat treatment
IEEE International Magnetics Conference, 1999
Thin Solid Films, 2007
In this study, pulsating electric current was applied during the electroless Ni plating process. ... more In this study, pulsating electric current was applied during the electroless Ni plating process. The applied current is controlled to avoid the formation of an immersion (displacement) deposit. The effects of the current density (0.5 and 1.0 A/dm 2 ), duty cycle (0 to 100%, in a step of 10%), and bath pH value (4.4 and 4.8) were investigated systematically. The as-plated coatings were examined by atomic force microscopy, transmission electron microscopy, X-ray diffraction, synchrotron X-ray absorption spectroscopy, etc. Amorphous or amorphous-like microstructure was obtained for all as-plated coatings and the phosphorus content was higher than 8.9 wt.%. Experimental results showed that pulsating electric current can initiate Ni nanocrystallization (∼ 5 nm), improve crystal growth, and accelerate electroless Ni deposition. An obvious increase in deposition rate was also observed with pulsating electric current.
Stoichiometric Study of Iron Sulfide Prepared by Mechanochemical Reaction
Materials Science Forum, 2007
Photocatalytic properties of nanocrystalline TiO2 thin film with Ag additions
Thin Solid Films, 2006
... This project was funded by Feng Chia University Distinguished Research Program, Grant number:... more ... This project was funded by Feng Chia University Distinguished Research Program, Grant number: FCU-92GB18. References. [1] C. He, Y. Yu, X. Hu and A. Larbot. Appl. Surf. ... Ceram. Soc., 76 (1993), p. 2093. [12] HE Chao, YU Yun, HU Xingfang and A. Larbot. J. Eur. Ceram. ...
Supercapacitive properties of spray pyrolyzed iron-added manganese oxide powders deposited by electrophoretic deposition technique
Thin Solid Films, 2008
Nanocrystalline iron-added manganese oxide powders were prepared by spray pyrolysis (SP) from man... more Nanocrystalline iron-added manganese oxide powders were prepared by spray pyrolysis (SP) from manganese acetate and iron nitrate solutions at 400 °C. The as-obtained powders were subsequently deposited onto graphite substrates via an electrophoretic deposition technique (EPD). The as-prepared powders were examined by transmission electron microscopy (TEM) and X-ray diffractometry (XRD); the electrochemical properties of the coatings were further examined by cycling
Thin Solid Films, 2010
In this study, CrTiAlN coatings were deposited on AISI 304 stainless steel by cathodic arc evapor... more In this study, CrTiAlN coatings were deposited on AISI 304 stainless steel by cathodic arc evaporation under a systematic variation of the substrate bias voltage. The coating morphology and properties including surface roughness, adhesion, hardness/elastic modulus (H/E) ratio, and friction behavior were analyzed to evaluate the impact of the substrate bias voltage on the coating microstructure and properties. The results suggest that for an optimized value of the substrate bias voltage, i.e. − 150 V, the CrTiAlN coatings showed increased Cr content and improved properties, such as higher adhesion strength, hardness, and elastic modulus in comparison to the coatings deposited by other substrate bias voltage. Moreover, the optimum coatings achieved a remarkable reduction in the steel friction coefficient from 0.65 to 0.45.
Thin Solid Films, 2011
CrTiAlN films were deposited on AISI 304 stainless steel by cathodic arc evaporation under a syst... more CrTiAlN films were deposited on AISI 304 stainless steel by cathodic arc evaporation under a systematic variation of the substrate bias voltage. The effects of substrate bias on the coating morphology and mechanical properties, such as structure, composition, adhesion, hardness and Young's modulus, were studied in details using field emission scanning electron microscopy, X-ray diffraction, electron probe microanalysis and indenter. Polarization test and immersion test were also carried out to evaluate the corrosion behavior of the various films. CrTiAlN films are nanocrystalline that exhibit a CrN/TiAlN multi-layered morphology. At the optimal value of substrate bias voltage (i.e., − 150 V), the CrTiAlN film showed an increased Cr content and improved properties, such as higher adhesion, higher hardness (38 ± 2 GPa), and greater Young's modulus (319 ± 16 GPa) vs. the films deposited at other substrate bias voltages. Moreover, the optimum film has better corrosion resistance in 3.5 wt.% NaCl and 20 vol.% HCl solutions.
Hybrid manganese oxide films for supercapacitor application prepared by sol–gel technique
Thin Solid Films, 2009
Hybrid films were prepared by adding various concentrations of meso-carbon microbeads (MCMB) duri... more Hybrid films were prepared by adding various concentrations of meso-carbon microbeads (MCMB) during sol–gel processing of manganese oxide films. The heat-treated films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). In addition, electrochemical performance of the MCMB-added Mn-oxide hybrid coatings was evaluated by cyclic voltammetry (CV) and compared with its unadded counterpart. Experimental results showed that Mn-oxide
Gas sensors with porous three-dimensional framework using TiO2/polymer double-shell hollow microsphere
Thin Solid Films, 2011
The correlations between the structures and gas-sensing properties of porous thin-film gas sensor... more The correlations between the structures and gas-sensing properties of porous thin-film gas sensors made of packed hollow spheres are investigated. For this purpose, hollow polymeric spheres were used as templates. Double-shell hollow spheres were prepared by encapsulating the polymeric hollow spheres with TiO2 shells. Solid polymeric spheres were used as templates for comparison. Porous thin-film gas sensor with interconnected three-dimensional pores was prepared by using the TiO2 encapsulated hollow spheres. The double-shell hollow spheres and porous titania films were characterized by XRD, BET, TEM and SEM. The gas-sensing properties of the sensors toward NO2 depend on the type of template and the three-dimensional porous structure of the films. Using the hollow sphere template and adding precursors during the film formation procedure help to prevent the collapse of hollow sphere and form the mesopores in films after removing the template. These films show enhanced gas sensitivity when compared to TiO2 polycrystalline films. Such improvement in sensitivity results from the porous architecture of the hollow microsphere films which not only increase the active surface area but also promotes the gas diffusion.
X-ray irradiation synthesis of PEG-coated Au-Pd nanoparticles
Nanotechnology, Jan 4, 2015
We demonstrate that the combination of x-ray irradiation and capping by polyethylene glycol (PEG)... more We demonstrate that the combination of x-ray irradiation and capping by polyethylene glycol (PEG) produces excellent flexibility in controlling the structure of Au-Pd nanoparticles while preserving their catalytic performance. We specifically adopted two different fabrication methods: co-reduction and seed-assisted reduction. In both cases, precursor composition plays an important role in controlling the phases and size of the bimetallic nanoparticles. The optimal catalytic performance is obtained with the highest Pd concentration and when the nanoparticles consist of a Au core and a Pd shell.
Uncapped Au-Pd colloidal nanoparticles show catalysis enhancement
RSC Adv., 2015
ABSTRACT The catalytic properties of Pd trigger a strong interest on the related catalysis by Au-... more ABSTRACT The catalytic properties of Pd trigger a strong interest on the related catalysis by Au-Pd nanoparticles. However, the analysis of such phenomena was complicated so far by the presence of capping. Using x-ray irradiation, we could produce uncapped Au-Pd nanoparticles and study their catalytic features, finding in particular their relation to the Pd content. Furthermore, the fabrication process is per se interesting, yielding excellent and flexibly controllable nanoparticles with a rather simple procedure.
Characterization and Modification of Nanocrystalline Iron Oxide Powders Prepared by an Inert Gas Condensation Technique
Materials Science Forum, 2007
A study on the corrosion and erosion behavior of electroless nickel and TiAlN/ZrN duplex coatings on ductile iron
Applied Surface Science
This study utilized electroless nickel (EN) and cathodic arc evaporation (CAE) technologies to de... more This study utilized electroless nickel (EN) and cathodic arc evaporation (CAE) technologies to deposit protective coatings onto ductile iron. Polarization corrosion tests were performed in 3.5 wt.% sodium chloride, and also erosion tests were carried out by using Al2O3 particles (∼177 μm in size and Mohr 7 scale) of about 5 g. Surface morphologies of the corroded and eroded specimens were observed separately. To further understand the coating effects on both the corrosive and erosive behavior of ductile iron, coating structure, morphology, and adhesion were analyzed using X-ray diffractormeter, scanning electron microscopy, and Rockwell-C indenter, respectively. The results showed that the EN exhibited an amorphous structure while the CAE-TiAlN/ZrN coating was a multilayered nanocrystalline. When the TiAlN/ZrN coated specimen with EN interlayer could effectively increase the adhesion strength between the CAE coating and substrate. Consequently, the combination of TiAlN/ZrN and EN de...
Influence of Fe3O4 Nanoparticles on Pseudocapacitive Behavior of the Charge Storage Process
Journal of Alloys and Compounds, 2015
ABSTRACT
Preparation and characterization of nanocrystalline Nb3Al alloy
Thin Solid Films, 2011
In this study, tungsten oxide films were prepared by sol-gel technique. Various amounts of multiw... more In this study, tungsten oxide films were prepared by sol-gel technique. Various amounts of multiwalled carbon nanotubes (MWCNTs) were added during sol-gel process to obtain hybrid WO 3 /MWCNT films. The original and hybrid films were characterized by thermogravimetric analysis, X-ray diffraction analysis, and scanning electron microscopy analysis, whereas the electrochromic performance was evaluated by measuring changes in the optical transmittance caused by potentiostatic charge-discharge intercalation. The influence on the structure and properties of tungsten oxide film due to MWCNT addition was also investigated. The results showed that all of the films were amorphous and exhibited porous microstructure. The electrochromic performance of pristine WO 3 film was improved by adding MWCNTs that served as a template for the growth of WO 3 and resulted in more porous microstructure. The hybrid tungsten oxide films with 0.1 wt.% MWCNT addition exhibited the best electrochromic performance.
Glass Forming Ability in Amorphous Ti50Cu35-xNi15Snx Alloys Prepared by Mechanical Alloying
Materials Science Forum, 2005
Nanostructured Materials, 1998
nanocrystalline Ag-Fe solidsolutions increase with increasing atomic percentage of iron. 01998 Ac... more nanocrystalline Ag-Fe solidsolutions increase with increasing atomic percentage of iron. 01998 Acta Metallurgica Inc.
Preparation of Mg-Y-Cu Bulk Metallic Glass by High Energy Ball Milling
Journal of Metastable and Nanocrystalline Materials, 2005
Characterization of iron nitride powders formed by mechanical alloying and atmospheric heat treatment techniques
Journal of the Chinese Institute of Engineers, 2001
... the same trend as the one found in several alloy systems, such as Ni-Nb (Lee and Koch, 1987) ... more ... the same trend as the one found in several alloy systems, such as Ni-Nb (Lee and Koch, 1987) and Co-Ta (Pee-Yew Lee and Ju ... Jack (1994) has reported the transient appearance of the α′′-Fe16N2 phase by aging a supersaturated Fe solid solution at 250°C. Different phase ...
Preparation of iron nitride powders through mechanical alloying and atmospheric heat treatment
IEEE International Magnetics Conference, 1999
Thin Solid Films, 2007
In this study, pulsating electric current was applied during the electroless Ni plating process. ... more In this study, pulsating electric current was applied during the electroless Ni plating process. The applied current is controlled to avoid the formation of an immersion (displacement) deposit. The effects of the current density (0.5 and 1.0 A/dm 2 ), duty cycle (0 to 100%, in a step of 10%), and bath pH value (4.4 and 4.8) were investigated systematically. The as-plated coatings were examined by atomic force microscopy, transmission electron microscopy, X-ray diffraction, synchrotron X-ray absorption spectroscopy, etc. Amorphous or amorphous-like microstructure was obtained for all as-plated coatings and the phosphorus content was higher than 8.9 wt.%. Experimental results showed that pulsating electric current can initiate Ni nanocrystallization (∼ 5 nm), improve crystal growth, and accelerate electroless Ni deposition. An obvious increase in deposition rate was also observed with pulsating electric current.
Stoichiometric Study of Iron Sulfide Prepared by Mechanochemical Reaction
Materials Science Forum, 2007
Photocatalytic properties of nanocrystalline TiO2 thin film with Ag additions
Thin Solid Films, 2006
... This project was funded by Feng Chia University Distinguished Research Program, Grant number:... more ... This project was funded by Feng Chia University Distinguished Research Program, Grant number: FCU-92GB18. References. [1] C. He, Y. Yu, X. Hu and A. Larbot. Appl. Surf. ... Ceram. Soc., 76 (1993), p. 2093. [12] HE Chao, YU Yun, HU Xingfang and A. Larbot. J. Eur. Ceram. ...
Supercapacitive properties of spray pyrolyzed iron-added manganese oxide powders deposited by electrophoretic deposition technique
Thin Solid Films, 2008
Nanocrystalline iron-added manganese oxide powders were prepared by spray pyrolysis (SP) from man... more Nanocrystalline iron-added manganese oxide powders were prepared by spray pyrolysis (SP) from manganese acetate and iron nitrate solutions at 400 °C. The as-obtained powders were subsequently deposited onto graphite substrates via an electrophoretic deposition technique (EPD). The as-prepared powders were examined by transmission electron microscopy (TEM) and X-ray diffractometry (XRD); the electrochemical properties of the coatings were further examined by cycling
Thin Solid Films, 2010
In this study, CrTiAlN coatings were deposited on AISI 304 stainless steel by cathodic arc evapor... more In this study, CrTiAlN coatings were deposited on AISI 304 stainless steel by cathodic arc evaporation under a systematic variation of the substrate bias voltage. The coating morphology and properties including surface roughness, adhesion, hardness/elastic modulus (H/E) ratio, and friction behavior were analyzed to evaluate the impact of the substrate bias voltage on the coating microstructure and properties. The results suggest that for an optimized value of the substrate bias voltage, i.e. − 150 V, the CrTiAlN coatings showed increased Cr content and improved properties, such as higher adhesion strength, hardness, and elastic modulus in comparison to the coatings deposited by other substrate bias voltage. Moreover, the optimum coatings achieved a remarkable reduction in the steel friction coefficient from 0.65 to 0.45.
Thin Solid Films, 2011
CrTiAlN films were deposited on AISI 304 stainless steel by cathodic arc evaporation under a syst... more CrTiAlN films were deposited on AISI 304 stainless steel by cathodic arc evaporation under a systematic variation of the substrate bias voltage. The effects of substrate bias on the coating morphology and mechanical properties, such as structure, composition, adhesion, hardness and Young's modulus, were studied in details using field emission scanning electron microscopy, X-ray diffraction, electron probe microanalysis and indenter. Polarization test and immersion test were also carried out to evaluate the corrosion behavior of the various films. CrTiAlN films are nanocrystalline that exhibit a CrN/TiAlN multi-layered morphology. At the optimal value of substrate bias voltage (i.e., − 150 V), the CrTiAlN film showed an increased Cr content and improved properties, such as higher adhesion, higher hardness (38 ± 2 GPa), and greater Young's modulus (319 ± 16 GPa) vs. the films deposited at other substrate bias voltages. Moreover, the optimum film has better corrosion resistance in 3.5 wt.% NaCl and 20 vol.% HCl solutions.
Hybrid manganese oxide films for supercapacitor application prepared by sol–gel technique
Thin Solid Films, 2009
Hybrid films were prepared by adding various concentrations of meso-carbon microbeads (MCMB) duri... more Hybrid films were prepared by adding various concentrations of meso-carbon microbeads (MCMB) during sol–gel processing of manganese oxide films. The heat-treated films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). In addition, electrochemical performance of the MCMB-added Mn-oxide hybrid coatings was evaluated by cyclic voltammetry (CV) and compared with its unadded counterpart. Experimental results showed that Mn-oxide