Bionic SERS chip with super-hydrophobic and plasmonic micro/nano dual structure

Abstract

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 (∼10 7) 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.

Manipulating “Hot Spots” from Nanometer to Angstrom: Toward Understanding Integrated Contributions of Molecule Number and Gap Size for Ultrasensitive Surface-Enhanced Raman Scattering Detection

“… However, the density of the Ag NPs was not high enough due to the Coulombic repulsion between NPs. Benefitting from thermal shrinkable performance of PVC, the interparticle gaps were reduced by heating over its glass-transition temperature ( T g ≈ 87 °C). Therefore, a layer of dense Ag NP film was obtained.…”

“…The thermal shrinking property of shape memory polymers (SMPs), such as polystyrene (PS) ,, and poly­(vinyl chloride) (PVC), provides a convenient method to adjust gap sizes of metal NPs, which are deposited on the polymer. Upon heating over the glass-transition temperature ( T g ), SMPs shrink in their lateral dimensions and compress the thin NP film on the surface of the polymer.…”

Graphene Oxide-Coated Metal–Insulator–Metal SERS Substrates for Trace Melamine Detection

“…A good way to achieve a SERS substrate with specific wavelength absorption is to artificially design plasmonic metasurfaces [ 22 , 29 , 31 , 32 ], which are a periodic arrangement of subwavelength meta-atoms with special shapes, such as nanodisks, nanopillars, nanogrids, etc. [ 33 , 34 , 35 , 36 , 37 , 38 ].…”

Preparation and Hydrophobicity of Bionic Structures Based on Composite Infiltration Model

“…The super-hydrophobic surface has super waterproof and self-cleaning properties, and has important application value in industrial production and daily life. However, the superhydrophobic surface also has some defects and shortcomings [9,10]; for example, it only exhibits superphobic characteristics for water with high surface tension, and is easily contaminated by organic oil stains with low surface tension. The "Cassie" of water on superhydrophobic surfaces, the contact state, is unstable, and external forces such as high pressure and impact can easily cause the "Cassie" contact state to change to the "Wenzel" contact state and lose its waterproof properties.…”