Flexible Glucose Sensors And Narrow-Band Photoabsorbing Films Based On High-Crystallized Single-Walled Carbon Nanotube

Single-walled carbon nanotube(SWCNT)has attracted attentions from researchers all over the world for its unique physical and chemical properties.The modification and separation of SWCNT are vital for the applications in biosensing and optoelectronic devices.However,conventional chemical methods for SWCNT modification usually increase defects on its surface,which may destroy its crystallinity and therefore significantly weaken its mechanical and electrical performance.The dissertation focuses on the fabrication,modification,and separation of high-crystallized SWCNT to make it functional for specific applications,which is divided into 5 chapters:Chapter 1 introduces the fabrication and characterization methods for SWCNT,including monochiral SWCNT,as well as the recent progress on CNT-based electrochemical and optoelectronic devices;Chapter 2 reports flexible double-layer SWCNT buckypaper modified by Ni O;Chapter 3 presents a green method to modify SWCNT buckypaper with Cu/reduced graphene oxide composites;Chapter 4 evaluates 3 different methods for the separation of semiconducting and monochiral SWCNT from as-grown SWCNT samples fabricated through different routes;Chapter 5 concludes the whole dissertation and discusses the perspectives.The achievements and conclusions are as follows:1.Double-layer flexible buckypaper decorated with Ni O nanoparticles was fabricated by a simple and scalable vacuum filtration method as the working electrode for electrochemical glucose sensor.One side of the buckypaper is composed of purified high-crystallized SWCNT,serving as supporting layer;while the other side comprises Ni O loaded SWCNT,serving as catalyst layer.2.Under optimized condition,the sensor based on Ni O decorated buckypaper exhibited a wide linear range of 0.1-9 m M for glucose determination with high sensitivity(2701?A m M^-1 cm^-2)and short response time(<2.5 s).Owing to its ideal flexibility,light weight(2 mg/cm²),high sensitivity and short response time,the buckypaper electrode is believed to be promising for wearable biosensors.3.By introducing graphene oxide as the intermediate between SWCNT and Cu,a green and low-cost strategy was developed for the fabrication of Cu/reduced graphene oxide decorated SWCNT buckypaper.Heat treatment in H₂ was found efficient to reduce graphene oxide and precursor for Cu nanoparticles simultaneously without destroying SWCNT.4.Cu/reduced graphene oxide decorated buckypaper was utilized as a flexible nonenzymatic electrode for electrochemical glucose sensor.The electrode is highly active for glucose oxidation and thus the sensor exhibits a wide linear range up to 25m M.Furthermore,this green strategy can be extend to modify SWCNT buckypaper with other functional metal or metal oxide nanoparticles.5.(6,5)monochiral and(7,5)/(7,6)quasi-monochiral SWCNT dispersions were acquired through gel chromatography sorting from Co Mo CAT and arc-discharge SWCNT,respectively.Both dispersions exhibited ultra-narrow bandwidths in their absorbing spectra,which are competitive with narrow-band dye sensitizers.6.Narrow-band photoabsorbing films were fabricated with monochiral SWCNT dispersions,in which SWCNT keeps its high crystallinity.The films could be transferred onto different substrates,including Si,SiO₂ and PET.