Fast Synthesis Of Gold Nanostar SERS Substrates Based On Nuclear Track Membrane By One-step Method

Since the high detecting sensitivity and rapid data acquisition capability,surface-enhanced Raman scattering（SERS）has been considered as a powerful technique for label-free ultrasensitive detection of chemical and biological analytes.SERS substrate is the basic part of SERS analysis,whose uniformity determines the applicability of this technology in all related areas.Therefore,seeking the fast,convenient and low-cost way to obtain the SERS substrate with high performance and reproducibility never stops in recent decades.In this work,the ion track-etched polycarbonate（PC）membrane with uniform nanopores was obtained by ion irradiation and chemical etching.This membrane was then creatively used for the acquirement of gold nanostar SERS substrates.The preparation conditions of gold nanostar SERS substrates were optimized,and the structure,SERS performance,stability and growth mechanism of the optimum samples were analyzed and discussed.The main findings are as follows:The monolayer gold nanostars can be obtained through a one-step redox reaction on the surface of the PC membrane,which can act as not only the base of SERS substrate but also the reaction adjuster.By optimizing the preparation conditions,the SERS substrate with uniform monolayer gold nanostars can be fabricated without any complicated procedures and costly equipment quickly（in 20 min）,and the obtained gold nanostars have good crystallinity.Meanwhile,the prepared flexible gold nanostar SERS substrate exhibits excellent Raman performance,which can effectively detect the analyte Rhodamine 6G（R6G）with the concentration as low as 1×10^-10 M.The SERS enhancement factor was determined to be around 3.70×10⁵.The SERS substrate preparation method developed in this thesis is cost effective,convenient,fast and easily scale up,which can satisfy the requests of the real applications in many fields.