Preparation And Applications Of Carbonaceous Fibers And Micro-spheres

The carbonaceous materials have an extended applications in bioinspired superhydrophobic hairy surfaces and microfluidics for their mild preparing conditions. The hairy surface is promising in water repelling and gas retaining, while the microfluidics has grown as technology for portable chemical and biological applications. This thesis was intended to modify diverse substrates with various patterned carbonaceous fiber (CF), and further integrate the CF with microfluidics for chemical and biological applications. On the other hand, the microfluidics had been also used as assistive technology for converting the biomass into carbonaceous particles. It mainly includes:Si, Glass, PDMS and PI had been successfully modified with CF by low temperature polymerization of acetylene. The CF morphology on diverse substrates relies on their catalyst deposition procedure. Si had the most homogeneous CF with diameter around300nm respected to its simplest catalyst deposition method. Microcontact imprinting was applied to pattern the Cu as Dot and Grid on Si surface for further patterned CF growth. The contact angle varied from145°to160°and170°due to the increased surface roughness and gas-liquid interface on the patterned CF. The grid-like CF acted as air-grid dividing and confining the algae cells in each3D micro-environment. No cell had been observed migrating to the neighbor microwell, and the air had retained inside the CF for at least7days. The overall surface of dot Cu pattern had been secondly plated and followed growing hierarchical CF (HCF). The contact angle of HCF was increased to170°comparing with plain CF surface. A dual channel microreactor with HCF embedded at the bottom channel was able to perform the invert gas-liquid laminar flow in upside-down way without any physical separators. The microreactor showed superior performance in Cu2+’s multi-step conjugation reaction. Silica selectively decorated HCF and successfully imitated the Sahinia molesta surface with strong water adhesion on superhydrophobic surface. The feasibility of introducing-NH2group on the silica area was further extended to the applications of immobilization of fluorescent dye and algae cells. The selective immobilization was meaningful for local chemistry and cell study.Various microreactors were used to study the in-situ growing of CF inside the microchannels. The results indicated that the Cu catalyst and microchannels strongly affected the CF’s morphology. The PDMS-Si gave the best results in growing aligned CF for the simplest and most homogeneous deposition of Cu. It indicated that less time (<30s) plated Cu preferred to form entangled CF whereas longer plating time (>60s) would like to grow well-aligned CF inside the microchannel, and the aligned CF became to entangle together with time increasing. The Pd decorated entangled CF acted as mixer and heterogeneouscatalyst in the microreactor showed good performance in Suzuki coupling reaction. Finally, biomass, such as glucose, had been continuously converted into carbonaceousparticles within stainless steel tube microreactor. The preliminary data demonstrated that themicro fluidic system was able to convert glucose into carbonaceous particles in30min underhydrothermal carbonization condition. The composition of the particles could be changed bychanging the starting materials. The particles were applied in metal-free catalysis andfluorescent particles.