| Gold nanoparticles have the characteristics of high specific surface area,anti-oxidation stability,various preparation methods and good biocompatibility.To expand the application of gold nanoparticles,we used two assembly methods to prepare two different functional nanomaterials:(1)I nterdigital electrodes(IDEs).Currently,the preparation methods of IDEs such as photolithography,plasma etching,and laser require complicated equipment,processes or expensive chemicals,which greatly increases the manufacturing cost and time of production.Therefore,this paper reports an IDEs prepared by interfacial assembly and plasma welding,and systematically studied its application in catalyti c sensing and photoelectric detection.(2)Broadband absorber.Broadband absorbers have attracted increasing interest from researchers over the past few decades because of th eir highly interesting full wavelength absorption and photothermal properties.The preparation and design of wide band absorbers have always been the focus of scientific research because they are largely dependent on absorbing materials.However,there are some challenges in the design and manufacture of light absorbers.In this paper,a novel wide band absorbing material(black gold)was prepared by means of salt-induced colloidal solution assembly and aggregation,and its properties were studied.The main research work of this paper is as follows:(1)Gold nanoparticles with different diameters were prepared by using the classic Frens method of reducing chloroauric acid with sodium citrate as the reducing agent.IDEs with catalytic properties and photoelec tric detection ability were successfully prepared by combining the self-assembly method of liquid-liquid interface with the plasma welding process.Due to its high conductivity and porous structure,it provides abundant active sites and can be used as a ba sic electrode for electrochemical glucose sensors and perovskite photodetectors.F or glucose catalysis,the peak oxidation current density of IDEs was 2.4 times higher than that of commercial IDEs,showing excellent electrocatalytic performance.At 590 nm and 680nm of incident light,the contact between the electrode and the active lay er was good,and the IDEs responsiveness was 1.65 and 1.6 0 m A/W,respectively,and the response time was 1.540/0.689 and 0.544/0.866 s.After several cycles,the current has no obvious weakening,which proves that it has good stability.(2)Using gold colloid with a diameter of 16 nm reduced by sodium citrate as raw material,black gold with wide-band absorption characteristics was prepared using DLVO theory and colloidal instability,and the morphology,spectral absorption,reflection,photothermal conversion and Raman performance was studied.Compared with flat gold,the prepared black gold thin film has no obvious reflected light path under the irradiation of 650 nm laser,and shows a strong absorption capacity(>80%)in the wide-band range of 400-1600 nm.The light absorption even reaches 94%in the visible wavelength range of 400-800 nm.In addition,under the irradiation of xenon lamp,the temperature of black gold rose b y 11.7?within 20 minutes,much higher than that of flat gold(3.4?),and it has the ability of high light heat conversion.At the same time,black gold has good Raman enhancement to rhodamine B under the excitation of 532,633,785 nm,and this wide wavelength Raman characteristic provides great convenience for Raman detection.Under the excitation of 785 nm light,black gold was used as the SERS substrate,and as low as 1×10-8 M thiram could be detected. |
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