研究目的
To enhance the refractive index sensitivity of gold nanodisks immobilized on electrically conducting indium tin oxide (ITO) substrates for combined electrochemical and optical platforms.
研究成果
The study demonstrated a simple method for enhancing the refractive index sensitivity of gold nanodisks on ITO substrates through substrate under-etching. The method allows for the combination of electrochemical and optical sensing capabilities on a single substrate, with potential applications in biosensing.
研究不足
The study is limited by the potential inhomogeneous broadening of the plasmonic resonance due to variations in size/aspect ratio of the nanodisks or in the Au-ITO interactions. The detailed shape of the nanostructure and substrate may also influence the calculated refractive index sensitivities.
1：Experimental Design and Method Selection
The study employed a simple method of substrate under-etching of gold nanodisks on ITO in 50 mM sulfuric acid to enhance refractive index sensitivity. The influence of an intermediate titanium adhesion layer on the etching pattern and time was investigated.
2：Sample Selection and Data Sources
Gold nanodisks were fabricated on ITO-coated borosilicate glass slides using hole-mask colloidal lithography (HCL). The samples were characterized using scanning electron microscopy (SEM) and optical spectroscopy.
3：List of Experimental Equipment and Materials
Gold nanodisks, ITO substrates, sulfuric acid, titanium adhesion layer, poly(3-aminophenol), scanning electron microscopy (FEI Magellan 400), UV–VIS–NIR spectrophotometer (Shimadzu UV-3600), fiber-coupled photodiode array spectrophotometer (BWTek Cypher H).
4：Experimental Procedures and Operational Workflow
Gold nanodisks were fabricated on ITO substrates, followed by substrate etching in sulfuric acid. The etching process was monitored in real-time using optical spectroscopy. The sensitivity to bulk refractive index changes was measured by injecting aqueous sucrose solutions of increasing concentrations.
5：Data Analysis Methods
The spectral shift and width of the plasmonic resonance were analyzed as a function of etching time. The refractive index sensitivity was calculated from the spectral shifts observed upon changing the refractive index of the surrounding medium.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
