• Bulletin of the Korean Chemical Society
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• 제31권11호
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• pp.3128-3132
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• 2010

A disposable solid-state pH sensor was realized by utilizing two nanoporous Pt (npPt) electrodes and a copolyelectrolytic junction. One nanoporous Pt electrode was to measure the pH as an indicating electrode (pH-IE) and the other assembled with copolyelectrolytic junction was to maintain constant open circuit potential ($E_{oc}$) as a solid-state reference electrode (SSRE). The copolyelectrolytic junction was composed of cationic and anionic polymers immobilized by photo-polymerization of N,N'-methylenebisacrylamide, making buffered electrolytic environment on the SSRE. It was expected to make. The nanoporous Pt surrounded by a constant pH excellently worked as a solid state reference electrode so as to stabilize the system within 30 s and retain the electrochemical environment regardless of unknown sample solutions. Combination between the SSRE and the pH-IE commonly based on nanoporous Pt yielded a complete solid-state pH sensor that requires no internal filling solution. The solid state pH sensing chip is simple and easy to fabricate so that it could be practically used for disposable purposes. Moreover, the solid-state pH sensor successfully functions in calibration-free mode in a variety of buffers and surfactant samples.

• 전기화학회지
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• 제10권3호
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• pp.203-206
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• 2007

Electrochemical reaction of glucose was regulated by the electrochemically active area of nanoporous platinum, which is controlled by ionic strength. The profile of the oxidation current of glucose vs. ionic strength was identical with that of the electrochemically active area. This result confirms that the nanopores are virtually opened for the electrochemical reaction of glucose when the ionic strength climbs over a specific concentration and implies that the electrochemical reactions on nanoporous electrode surfaces can be controlled by concentration of electrolyte.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2007년도 제32회 학술대회 초록집
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• pp.48-48
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• 2007

• Journal of Electrochemical Science and Technology
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• 제4권1호
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• pp.41-45
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• 2013

Platinum is a well known element which shows a significant electrocatalytic activity in many important applications. In glucose sensor, because of the poisoning effect of reaction intermediates and the low surface area, the electrocatalytic activity towards the glucose oxidation is low which cause the low sensitivity. So, we fabricate a nanoporous PtZn alloy electrode by deposition-dissolution method. It provides a high active surface and a large enzyme encapsulating space per unit area when it used for an enzymatic glucose sensor. Glucose oxidase was immobilized on the electrode surface by capping with PEDOT composite and PPDA. The composite and PPDA also can exclude the interference ion such as ascorbic acid and uric acid to improve the selectivity. The surface area was determined by cyclic voltametry method and the surface structure and the element were analyzed by Scanning Electron Microscope (SEM) and Energy Dispersive X-ray spectroscopy (EDX), respectively. The sensitivity is $13.5{\mu}A/mM\;cm^2$. It is a remarkable value with such simply prepared senor has high selectivity.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2007년도 춘계학술대회
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• pp.230-233
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• 2007

A system of anodic process of aluminum thin film has implemented for nanofabrication. The manufactured equipment consists of three main parts: chiller, reaction bath and power supply. The chiller module consists of refrigeration compressor, copper tube and coolant with a thermostat. The reaction bath has kept in same temperature as a thermodynamic canonical ensemble system during the anodic reaction process. The magnetic bar has stirred oxalic acid in bath for uniform reaction. The DC power supply has applied into two electrodes, aluminum for anode and platinum for cathode in the oxalic acid. The anodization process results in the formation of nanoporous thin films.

• 한국진공학회지
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• 제19권2호
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• pp.81-90
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• 2010

층과 층 사이의 정전기적인력, 수소결합 또는 공유결합을 이용하여 층당 두께를 수 옹스트롱에서부터 수십 나노미터까지 제조할 수 있으며 박막의 표면 형태를 흡착시키고자 하는 물질 및 박막 후처리 공정을 통해 제어할 수 있으며 더 나아가, 삽입하는 물질의 특성에 따라 박막의 기능성을 집적화 및 다양화시킬 수 있다. 본 연구에서는 이러한 층상자기조립방법의 특성을 이용하여 반사방지막, 초소수성 필름 및 전기화학센서로의 응용가능성을 제시하였다. 반사방지막의 경우, 구형의 블록공중합체를 유리기판 위에 다층박막으로 적층시킴으로써 박막 굴절률을 1.25까지 감소시켰고 이를 통해 약 99.5%의 빛 투과도를 달성할 수 있었다. 더 나아가 바이오물질인 엔자임을 다층박막에 삽입시킬 경우, 활성 산소를 분해시키는 전기화학센서로의 제조가 가능함을 보인다. 본 연구는 본인이 이미 발표한 논문(J. Am. Chem. Soc. 128, 9935 (2006); Adv. Mater. 19, 4364 (2007); Electro. Mater. Lett. 3, 163 (2007))들을 정리하여 층상자기조립법에 관해 소개하는 논문이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1474-1475
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• 2008

본 논문에서는 nanoporous Pt (Platinum) 전극을 이용한 무효소 혈당센서의 생체 적합성 및 전류응답 특성 향상을 위해 다양한 패키징 방법이 제안되었다. 생체적합성을 갖는 Nafion 멤브레인을 dipping, spin coating, chemical bonding 방법으로 패키징 한 후, 다양한 글루코오스 농도의 혈장, 전혈에서 특성을 분석, 비교하였다. 단백질 등이 포함되지 않은 환경에서 spin coating 방법으로 패키징한 센서의 전류응답 특성은 가장 좋았지만, 혈장 및 전혈에서는 dipping, chemical bonding 방법으로 패키징한 센서의 전류응답 특성에 미치지 못했다. Nafion film을 센서와 chemical bonding한 센서의 혈장에서 sensitivity 는 0.32 ${\mu}A/mM{\cdot}cm^2$ 이었다. 한편, 전혈에서 bare 센서가 급격한 bio-fouling 현상을 보이는 반면 패키징한 센서는 글루코오스 농도에 따라 일정한 전류변화를 보였다. 이는 Nafion을 이용하여 패키징한 무효소 혈당 센서가 생체환경에 적합할 뿐 아니라 생체이식형 및 연속 측정 가능한 시스템에 적용 가능함을 보여준다.

• 대한금속재료학회지
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• 제56권12호
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• pp.910-914
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• 2018

Since catalyst technology is one of the promising technologies to improve the working performance of next generation energy and electronic devices, many efforts have been made to develop various catalysts with high efficiency at a low cost. However, there are remaining challenges to be resolved in order to use the suggested catalytic materials, such as platinum (Pt), gold (Au), and palladium (Pd), due to their poor cost-effectiveness for device applications. In this study, to overcome these challenges, we suggest a useful method to increase the surface area of a noble metal catalyst material, resulting in a reduction of the total amount of catalyst usage. By employing block copolymer (BCP) self-assembly and nano-transfer printing (n-TP) processes, we successfully fabricated sub-20 nm Pt line and cross-bar patterns. Furthermore, we obtained a highly ordered Pt cross-bar pattern on a Ni thin film and a Pt-embedded Ni thin film, which can be used as hetero hybrid alloy catalyst structure. For a detailed analysis of the hybrid catalytic material, we used scanning electron microscope (SEM), transmission electron microscope (TEM) and energy-dispersive X-ray spectroscopy (EDS), which revealed a well-defined nanoporous Pt nanostructure on the Ni thin film. Based on these results, we expect that the successful hybridization of various catalytic nanostructures can be extended to other material systems and devices in the near future.