Rahong, Sakon
Loading...
Preferred name
Rahong, Sakon
Alternative Name
Rahong, S.
Main Affiliation
Email
sakon.ra@kmitl.ac.th
11 results
Now showing 1 - 10 of 11
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Superparamagnetic nanoparticles encapsulation via droplet-based microfluidics for targeted drug delivery system(2019-01-01); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Improved Efficiency of Polymer Solar Cells by means of Coating Hole Transporting Layer as Double Layer Deposition(2017-10-20); ; ; Polymer solar cells is one of the promising technologies that gain tremendous attentions in the field of renewable energy. Optimization of thickness for each layer is an important factor determining the efficiency of the solar cells. In this work, the optimum thickness of Poly(3,4-ethylenedioxythione): poly(styrenesulfonate) (PEDOT:PSS), a famous polymer widely used as hole transporting layer in polymer solar cells, is determined through the analyzing of device's photovoltaic parameters, e.g. short circuit current density (J<inf>sc</inf>), open circuit voltage (V<inf>oc</inf>), fill factor (FF) as well as power conversion efficiency (PCE). The solar cells were prepared with multilayer of ITO/PEDOT:PSS/PCDTBT:PC<inf>70</inf>BM/TiO<inf>x</inf>/Al by rapid convective deposition. In such preparation technique, the thickness of the thin film is controlled by the deposition speed. The faster deposition speed is used, the thicker film is obtained. Furthermore, double layer deposition of PEDOT:PSS was introduced as an approach to improve solar cell efficiency. The results obviously reveal that, with the increase of PEDOT:PSS thickness, the increments of J<inf>sc</inf> and FF play the important role to improve PCE from 3.21% to 4.03%. Interestingly, using double layer deposition of PEDOT:PSS shows the ability to enhance the performance of the solar cells to 6.12% under simulated AM 1.5G illumination of 100 mW/cm<sup>2</sup>. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A disposable polydimethylsiloxane microdevice for DNA amplification(2010-02-05) - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Modulation spectroscopy study of inorganic-organic hybrid quantum well-like nanostructures(2007-08-28); The optical transition energy in zinc selenide (ZnSe)/tris(8- hydroxyquinoline) aluminum (Alq3) /N,N'-Bis(3-methyphenyl)-N,N -diphenylbenzidine inorganic-organic hybrid quantum well-like nanostructures (hybrid QW-like nanostructure) with well thickness of Aq3 from 10 to 50 nm were investigated by modulation spectroscopy as electroreflectance (ER) measurements. ER features due to optical transition energy were observed in the hybrid QW of well thickness. The transition energies were determined by fitting the ER spectra to the theoretical line-shape expression. The subband transition energy decreased with increasing well thickness might be due to the increase of well results in the reduction of quantum confinement energy. © 2007 IEEE. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Study of optical and electrical properties of tin doped cobalt-phthalocyanine thin films prepared by thermal co-evaporation(2018-09-05); ; ; The aim of this research is to study the specific properties e.g. surface morphology, optical absorption as well as electrical conductivity of tin-doped cobalt-phthalocyanine (CoPc) thin film prepared by thermal co-evaporation. The concentration of tin metal dopant is controlled via evaporation rate during film's preparation. The change of tin quantity leads to the significant changes not only in morphology but also in molecular packing of the doped films. Moreover, the dramatic increase in both carrier mobility and carrier concentration should provide the enhancement in electrical conductivity of the doped films. By controlling the specific properties of the tin-doped CoPc thin film, the increasing efficiency of optoelectronic applications based on metal-phthalocyanine could be achieved. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Phase formation polycrystalline vanadium oxide via thermal annealing process under controlled nitrogen pressure(2017-10-20); ; ; This article provides an approach to improve and control crystal phases of the sputtering vanadium oxide (V<inf>x</inf>O<inf>y</inf>) thin films by post-thermal annealing process. Usually, as-deposited V<inf>x</inf>O<inf>y</inf> thin films at room temperature are amorphous phase: post-thermal annealing processes (400 °C, 2 hrs) under the various nitrogen (N<inf>2</inf>) pressures are applied to improve and control the crystal phase of V<inf>x</inf>O<inf>y</inf> thin films. The crystallinity of V<inf>x</inf>O<inf>y</inf> thin films changes from amorphous to α-V<inf>2</inf>O<inf>5</inf> phase or V<inf>9</inf>O<inf>17</inf> polycrystalline, which depend on the pressure of N<inf>2</inf> carrier during annealing process. Moreover, the electrical resistivity of the V<inf>x</inf>O<inf>y</inf> thin films decrease from 10<sup>5</sup> Ω cm (amorphous) to 6×10<sup>-1</sup> Ω cm (V<inf>9</inf>O<inf>17</inf>). Base on the results, our study show a simply method to improve and control phase formation of V<inf>x</inf>O<inf>y</inf> thin films<inf>.</inf> - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Influence of the annealing temperature on the organometallic halide perovskite phase formation via CH3NH3Cl as additive in sequential deposition process.(2019-01-01); ; ; Organometallic halide perovskite materials with the general formula ABX<inf>3</inf> have been recently interested as active layers in perovskite solar cells. It is well known that the O<inf>2</inf> is the main problem for fabricated perovskite solar cells. Usually, the perovskite thin film need to be prepared in the N<inf>2</inf> atmosphere or in the glove box. In this research, the metal halide perovskite CH<inf>3</inf>NH<inf>3</inf>PbI<inf>2</inf>Cl thin films were successfully deposited using spin-coating technique via a single step solution deposition and CH<inf>3</inf>NH<inf>3</inf>Cl as additive in sequential deposition process in the open air. The effect of annealing temperature on the organolead halide perovskite phase formation of CH<inf>3</inf>NH<inf>3</inf>PbI<inf>2</inf>Cl thin film was investigated. The phase formation as well as crystal structure were investigated by X-ray diffractometer, and we found that organolead halide perovskite thin film exhibited a pure phase perovskite without the unwanted phases. The crystallinity of the perovskite thin film was enhanced significantly by increasing the annealing temperature, and a single phase of the perovskite phase was observed by increment of the annealing temperature that is above 100<sup>O</sup>C. In addition to this, the growth of crystallinity in the halide perovskite thin film was increased with increasing heat treatment temperature. Furthermore, the morphology variation of the thin films were examined by Field Emission Scanning Electron Microscopy. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Modification of the optical properties of polydimethylsiloxane (PDMS) for photonic crystal biosensor application(2010-05-05); ; Hruanun, ChandechThe sensitivity of a photonic crystal optical biosensor device can be enhanced through the difference in effective refractive index of dielectric materials. In this work, we report the optical modification of refractive index of PDMS from 1.41 to above, by incorporating the additive materials to enhance the sensitivity of photonic crystal optical biosensor devices. The refractive index of mixed-PDMS materials are measured by ellipsometry technique. The surface and cross section morphologies are characterized by Field-Emission Scanning Electron Microscope (FESEM) and Atomic Force Microscope (AFM). The grating structure of 800 nm period PDMS with low refractive index was fabricated by Nano-Imprinting Lithography (NIL) then the mixed-PDMS with high refractive index was spun on the periodic PDMS as photonic crystal device. The sensitivity of devices is characterized and demonstrated by reflection spectra intensity of fluids on surface of the devices. ©2010 IEEE. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Observation of optical transition energy in ZnSe/tris(8-hydroxyquinoline) aluminum (Alq3)/ZnSe single quantum wells by photoreflectance spectroscopy(2004-03-01); ; ; The optical transition energy in ZnSe/tris(8-hydroxyquinoline) aluminum (Alq3)/ZnSe single quantum wells (SQW) thin films with well thickness from 5 to 50 nm was investigated by room-temperature photoreflectance (PR) measurements. PR features due to optical transition energy were observed in the SQWs of well thicknesses. The transition energies were determined by fitting the PR spectra to the theoretical line-shape expression. The transition energy decreased with increasing well thickness. © 2003 Elsevier B.V. All rights reserved. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Control the crystal growth of Al-doped ZnO thin film prepared by pulsed laser deposition and the influences on its optical and electrical properties(2017-10-20); ; ; In this work, highly transparent and highly conductive thin films of Al-doped ZnO (AZO) are achieved by pulsed laser deposition (PLD). By changing substrate temperature in the range of room temperature to 500°C during the deposition process, the preferential growth direction of AZO crystal is controlled and, therefore, the surface morphology, optical and electrical properties of AZO thin films are able to be manipulated. X-ray diffractograms as a function of the substrate temperature clearly illustrate the ability to control the preferential growth direction of AZO. At the low substrate temperature, the growth along [002] direction corresponding to c-axis of hexagonal ZnO is only observed. By elevating the substrate temperature, not only crystallinity of AZO thin film is further improved but also the competition of crystal growth along the [002], [001] and [101] directions are occurred due to the increase of total energy and surface mobility of cluster/atom. The AZO films obtained by all preparation conditions exhibit an n-type semiconducting characteristics, furthermore, the carrier concentration and the carrier mobility of AZO thin films can be optimized to reach 4.10×10<sup>20</sup> cm<sup>-3</sup> and 7.53 cm<sup>2</sup>/Vs, respectively. The excellences in both carrier concentration and mobility of AZO thin film lead to very low resistivity of 2.08×10<sup>-3</sup> cm. In addition, the wide optical band gap of ∼3.50 eV together with the high transparency over 90% in visible region is obtained from the AZO thin films. The exceptional optical and electrical properties of AZO thin film demonstrate that such material has enough potential to become a promising candidate using in optoelectronic applications.