플렉스블 은나노와이어 투명전극의 개발과 과산화수소의 전기화학적 검출

Abstract

본 논문에서는 플렉스블하고 투명한 은나노와이어 필름의 제작방법을 보고하였다. 진공여과법을 이용하여 균일한 실버나노와이어 네트워크를 나이트로셀룰로스 막 위에 형성하였다. 불투명의 하얀 MCE막은 아세톤 증기로 처리하여 투명도를 높였다. 제작된 실버나노와이어 필름은 13 Ω/sq 의 낮은 평균 저항과 67%의 투명도를 가지며, 반복적인 접착시험과 구부림시험 그리고 열과 NaCl 수용액에 대해서 높은 저항력을 보였다. 은나노와이어 필름은 소프트 리소그래피와 수용액 기반의 화학적 애칭 기술에 의해 패터닝되었다. 감광성 고분자 아래 있던 부분은 애칭 후에도 전도도와 투명도를 유지하는 반면, 애칭된 부분에서는 저항과 투명도가 증가했다. 패턴된 은나노와이어 전극의 전자 소자로의 적합성은 패턴된 은나노와이어 필름위에 간단한 LED 회로를 구성하여 증명되었다. 은나노와이어 전극을 과산화수소 검출을 위한 전기화학 센서로 사용했을 때 검출 한계 값은 46 µM (S/N = 3)이었고, 빠른 반응시간 (within 2 s), 그리고 높은 민감도 (749 μA·mM−1·cm−2 와 1640 μA·mM−1·cm−2)를 보였다. 은나노와이어 센서는 보통 생리학적인 샘플에 존재하는 아스코르브산과 같은 다른 방해 종의 영향을 덜 받았고, 이 결과는 은나노와이어 센서가 과산화수소를 선택적으로 전기환원 시킨다는 것을 나타낸다. 또한, 오래 저장된 후에도 과산화수소에 대하여 안정적인 전기화학적 반응을 보이는 것을 확인했다.|We present a simple method to fabricate flexible, transparent silver nanowire (AgNW) films. Homogenous AgNW networks were formed on a mixed cellulose ester (MCE) membrane by vacuum filtration and were easily transferable to self-adhesive poly(ethylene terephthalate). The opaque, white MCE membrane became transparent after being subjected to hot acetone vapor. The fabricated AgNW films had an average resistivity of 13 Ω/sq and a transmittance of approximately 67%. Moreover, the AgNW films showed excellent mechanical properties in repeated adhesion tests and bending tests. The AgNW films also showed good resistance against heat and NaCl solutions. AgNW films were patterned by a combination of soft lithography and a solution-based chemical etching technique. The area under the photoresist polymer maintained its conductivity and transmittance after etching, whereas increased resistance and transparency were observed in the etched area. The suitability of the patterned AgNW electrodes for electronic devices was demonstrated via a simple LED chip array. After using standard photolithography to define the working area, AgNW films were used as sensor electrodes for the electrochemical detection of hydrogen peroxide (H2O2). The AgNW sensors displayed a reasonable detection limit of 46 µM (S/N = 3), a rapid response time (within 2 s), and high sensitivity (749 μA·mM−1·cm−2 and 1640 μA·mM−1·cm−2). Furthermore, the AgNW sensor was resistant to other potential interfering electroactive species commonly present in physiological samples such as L-ascorbic acid, glucose, and sodium oxalate. These results indicate that the AgNW sensor is selective for electroreduction of H2O2. Additionally, the developed sensor exhibited a stable amperometric response to the reduction of H2O2 even after extended storage.; We present a simple method to fabricate flexible, transparent silver nanowire (AgNW) films. Homogenous AgNW networks were formed on a mixed cellulose ester (MCE) membrane by vacuum filtration and were easily transferable to self-adhesive poly(ethylene terephthalate). The opaque, white MCE membrane became transparent after being subjected to hot acetone vapor. The fabricated AgNW films had an average resistivity of 13 Ω/sq and a transmittance of approximately 67%. Moreover, the AgNW films showed excellent mechanical properties in repeated adhesion tests and bending tests. The AgNW films also showed good resistance against heat and NaCl solutions. AgNW films were patterned by a combination of soft lithography and a solution-based chemical etching technique. The area under the photoresist polymer maintained its conductivity and transmittance after etching, whereas increased resistance and transparency were observed in the etched area. The suitability of the patterned AgNW electrodes for electronic devices was demonstrated via a simple LED chip array. After using standard photolithography to define the working area, AgNW films were used as sensor electrodes for the electrochemical detection of hydrogen peroxide (H2O2). The AgNW sensors displayed a reasonable detection limit of 46 µM (S/N = 3), a rapid response time (within 2 s), and high sensitivity (749 μA·mM−1·cm−2 and 1640 μA·mM−1·cm−2). Furthermore, the AgNW sensor was resistant to other potential interfering electroactive species commonly present in physiological samples such as L-ascorbic acid, glucose, and sodium oxalate. These results indicate that the AgNW sensor is selective for electroreduction of H2O2. Additionally, the developed sensor exhibited a stable amperometric response to the reduction of H2O2 even after extended storage.