Preparation And Application Of Ferrocene-based Polymeric Photonic Crystals

Polymeric photonic crystals with different response based on various functional materials have broad application prospects in anticounterfeiting and information storage,photocatalysis,solar cells and chemical and biological sensors.The ferrocene group is widely used in industry,medicine,aerospace,energy conservation and functional materials due to its good oxidation-reduction activity and stability in aqueous and aerobic media.Based on the above,this paper introduces ferrocene group into polymeric photonic crystal and studies their sensing application to temperature and different molecules.The main research results are summarized as follows:1.A ferrocene-based polymeric photonic crystal sensor with temperature response was prepared using vinyl ferrocene and methacrylic acid as functional monomers.The effect of molar ratio of functional monomer to cross-linking agent and vinyl ferrocene on the sensor was studied.It was found that the best sensing effect was obtained when the ratio of the three was 5:0.1:1.5.When the sensor is placed in 5%-30%hydrogen peroxide solution,it is found that the effect of thermal response in 20%hydrogen peroxide solution is the best.The visual response of the sensor to 30℃,50℃,80℃,90℃ and 100℃ was investigated under the optimal conditions.It was found that the reflection shifted to 13 nm,39 nm,84 nm,121 nm and 162 nm respectively,and the macroscopic color of the sensor changed from orange to blue with the increase of temperature.In addition,the response of the sensor in different ionic strength,pH and tap water was studied,and it was found that the sensor had good adaptability and stability.2.Based on the specific catalytic reaction of catalase,the application of ferr ocene-based polymeric photonic crystal sensor in the detection of hydrogen pero xide and catalase was studied.Through the influence of the molar ratio of functio nal monomer methacrylic acid to crosslinking agent,vinyl ferrocene and redox c onditions on the sensor,it was found that the sensing effect was best when the rat io of the three was 5:0.1:1.5 and the catalyst was present.Under the optimal cond itions,the response detection of 5%,10%,15%,20%,25%and 30%hydrogen pe roxide solution was carried out.The reflection of the sensor shifted blue by 2 nm,57 nm,136 nm,156 nm,228 nm and 253 nm,and the color also changed from re d to purple on the macro level.The response time only took 1 minute.In the actu al sample,the sensor also shows good adaptability and stability.In addition,whe n the sensor responds to the catalase of 50 U·mL-1,100 U·mL-1,200 U·mL-1,400 U·mL-1 and 600 U·mL-1,the reflection shifts to 12 nm,32 nm,40 nm,68 nm and 116 nm respectively,and the color changes from orange to blue-green on the ma cro level.It was found that the sensor had good selectivity and stability by changi ng the type of enzyme and adding different ions under the same conditions.3.Based on the inhibition of sodium nitrite on catalase activity,a visual sodium nitrite photonic crystal sensor was prepared using hydroxyethyl methacrylate and vinyl ferrocene as functional monomers.Because sodium nitrite can inhibit the activity of catalase and then affect the redox process of the system,the blue shift of the photonic crystal is reduced,and the detection of sodium nitrite is realized.It was found that when the molar ratio of functional monomer to crosslinking agent and vinyl ferrocene was 5:0.1:1.5,the catalase activity was 400 U·mL-1 and mixed with sodium nitrite for 30 minutes,the sensor response was the best.The sensor response to 5×10-1 g/L,5×10-2 g/L,5×10-3 g/L,5×10-4 g/L and 5 × 10-5 g/L sodium nitrite was studied,it was found that the reflection of the sensor shifted blue by 17 nm,43 nm,82 nm,89 nm and 100 nm respectively,and the color changed from orange to emerald green on the macro level.By changing the acid-base environment and ionic strength of the response solution,it is found that the sensor has good stability and anti-interference ability.At the same time,the application of the sensor in the detection of sodium nitrite content in actual samples such as ham sausage was preliminarily explored.