Interface Design And Surface Functionalization Of Flexible Materials By Gas-liquid Plasma

Flexible materials and devices have wide application prospects in the fields of electronic information,energy ? environment,and biomedicine due to their flexibility,lightness,and structural varieties.Flexible fiber materials have exhibited some unique benefits in terms of lighter weight,better flexibility,and multi-level integration that make them an important class of basic materials.With the highly development of smart wearable system and advanced energy technology,critical requirements for flexible fiber materials have been proposed.The surface and interface properties of the flexible fiber materials are the key factors for their functional and practical applications.At present,there are many methods to modulate the surface and interface properties of flexible fiber materials.However,there remain many intractable problems such as complicated preparation processes and excessive usage of chemical reagents,etc.As a typical approach for surface modification,low temperature plasma technology has been extensively applied to modify the fiber materials surfaces due to its high-efficiency and eco-friendly.In particular,nano-coatings or nano-structures prepared by plasma on the surfaces of fibers have been considered to be a significant way to functionalize flexible fiber materials.Unfortunately,the chemical reactions initiated by gas discharge plasma involve the formation of free radicals,resulting in poor product selectivity.More importantly,the fabrics have a large number of micropores,leading to a non-uniform physical and chemical effect on the surface modification.Recently,gas-liquid plasma technology that gas discharge generated with liquid has shown great potential for the synthesis of nanomaterials and nanocomposites.The liquid in the gas-liquid plasma can offer a variety of chemical reaction paths,and improve the uniformity of nanomaterial synthesis.The technology provides a new possibility to design and prepare uniform nanostructures on the surface of flexible fiber materials.In this work,a flow-type gas-liquid plasma system and a static-type gas-liquid plasma system under atmospheric pressure were designed and constructed according to the requirements of the surface functionalization of flexible fiber materials.Based on the gas-liquid plasma systems,a green and mild strategy has been developed for the deposition of nanomaterials,which created corrosion-resistant surface on glass fiber and metallized surface on carbon fiber,respectively.Surface functionalization of flexible fiber materials was achieved.The researches included the construction and characteristic analysis of the flow-type gas-liquid plasma system,the creation of the corrosion-resistant surface on glass fiber by the flow-type gas-liquid plasma,the construction and characteristic analysis of the static-type gas-liquid plasma system,and the creation of the metallized surface on carbon fiber by the static-type gas-liquid plasma system.The main contents are summarized as follows:1.According to the previous researches and experimental exploration,a flow-type gas-liquid plasma system with liquid carried by gas directly was designed and constructed.The system was composed of plasma generator,power module,gas supply module,liquid supply module,motion platform module and plasma diagnosis module,etc.The electrical characteristics,optical characteristics and thermal characteristics of the system were analyzed.The results showed that the discharge in the gas-liquid plasma system can be stable,and the liquid can react with active particles such as high-energy electrons and excited argon atoms in the plasma system.This can ensure that the gas-liquid reaction are properly performed,which may lay a foundation for the surface functional modification of the flexible fiber materials.2.With the flow-type gas-liquid plasma system,the corrosion resistant films contained silicon and oxygen were prepared by using the organic monomer methyltrimethoxysilane(MTMS)as the reaction solution.The AC high-voltage power supply was applied to generate an argon plasma jet.The influence of the flow rate of the precursor solution on the deposition process,the surface morphology and surface chemical structure of the as-prepared film was systematically investigated.In consideration of the physical and chemical properties of the as-prepared film,the optimal conditions of the flow rate were obtained.The optimal samples can effectively prevent the corrosion of hydrochloric acid solution(2 mol/L)for 6 hours,which suggests that the corrosion-resistant surface on glass fiber was created successfully.3.According to the previous researches and experimental analysis,a static-type gas-liquid plasma system with aqueous solution as the cathode was designed and constructed,which consisted of plasma generator,excitation power module,gas supply module and plasma diagnosis module.The electrical characteristics,optical characteristics and solution characteristics of the system were investigated.The results indicated that the discharge in the gas-liquid plasma system can be stable,and the gas-liquid reaction can be performed.Varieties of active particles in the solution can promote the chemical reaction,which will be helpful for the surface functional modification of the flexible fiber materials.4.With the static-type gas-liquid plasma system,the nanostructured metal hydroxides were prepared on the surface of carbon fibers by adding metal particles to the aqueous solution.The high-voltage power supply was used to generate gas-liquid interface plasma.The chemical properties of aqueous solutions with metal particles were systematically investigated.The different metallized nanostructures on the carbon fiber surface were observed.The metal hydroxides on the carbon fiber surface were identified by the chemical analysis.Compared with carbon fiber,the as-prepared carbon fiber with nanostructured metal hydroxides exhibited a better electrochemical performance,which indicated that the metalized surface of carbon fiber was created successfully.