【摘 要】
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Natural surface-enhanced Raman spectroscopy (SERS) chips based on plants or insects have gained increased attention due to their facile characteristics and low costs. However, such chips remain a major challenge for practical application because of poor r
【机 构】
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CASCenterforExcellenceinNanoscience,NationalCenterforNanoscienceandTechnology,Beijing100190,ChinaUni
【出 处】
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PhotonicsResearch
论文部分内容阅读
Natural surface-enhanced Raman spectroscopy (SERS) chips based on plants or insects have gained increased attention due to their facile characteristics and low costs. However, such chips remain a major challenge for practical application because of poor reproducibility and stability as well as unavoidable damage to the surface structure during coating metal and uncontrolled dehydration. By using a simple wrinkling method, we develop a new route to fabricate a low-cost bionic SERS chip for practical detection. Inspired by the taro leaf, we fabricate a SERS chip with a super-hydrophobic and plasmonic micro/nano dual structure, and its structure parameters can be optimized. Compared with the natural taro-leaf SERS chip, our artificial chip exhibits Raman signals with an order of magnitude higher sensitivity (~10 9 M) and enhancement factor (~107) under the illumination of weak laser radiation, demonstrating that our SERS chip has great potential in biological detection. The excellent performances of our bionic SERS chip are attributed to a synergy of optimized micro-wrinkle and nano-nest, which is verified by experiment and simulation. We believe our bionic chip could be a promising candidate in practical application due to its merits such as simple fabricating process, optimizable structure, low cost, excellent homogeneity, high sensitivity, and stability.
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