Nanostructured resorcinol-formaldehyde ink for 3D direct writing
- PDF / 765,501 Bytes
- 10 Pages / 584.957 x 782.986 pts Page_size
- 82 Downloads / 220 Views
We designed a resorcinol-formaldehyde (RF) sol–gel ink for direct ink writing of the microlattices. To improve the formability, the fresh microlattices were strengthened by surface catalysis with HCl atmosphere. After supercritical drying and carbonization, the sample’s specific surface area was 631 m2/g and the average pore size was 3.81 nm. Both RF aerogel and carbonized RF aerogel samples had millimeter-scale pore, micron-scale pore, and nanoscale skeleton. The pore and skeleton could provide high surface area and diffusion channels, which were beneficial to the adsorption performances. The carbonized RF aerogel sample fully adsorbed Dulbecco’s modified eagle medium in 250 min, which exhibited a good capacity of quick adsorption and indicated the potential application for cell supports.
I. INTRODUCTION
The three dimensional (3D) direct writing technology has great potentials and advantages in the fabrication of complex 3D microstructure. This technology exhibits the advantages of simple equipment, adjustable composition, low cost, high efficiency, and potentially high resolution.1 Lewis’ group devolved a lot of novel 3D direct writing equipment and inks with various chemical compositions.2–8 In 2015, Worsley’s group developed the graphene-based colloid ink for direct writing. This technique showed the exquisite structure and unique properties of the periodic graphene aerogel microlattices. This is perhaps the first report concerning the direct writing ink with the primary size about 10 nm. The introduction of the nanoscale microstructure of aerogels into the periodic microlattices may induce novel functions or applications for board interests.2–15 Graphene-based colloid is a solid–liquid hybrid system, showing relatively high viscosity, good mechanical properties, and high formability.16–20 Moreover, the ink normally exhibits the perfect character of non-Newtonian fluids. This fluid property is suitable for direct ink writing.21 Thus, almost all of the relative reports are focused on the direct writing of graphene-based ink.18–26 The traditional sol–gel colloids may have great potentials for 3D direct writing of the support, adsorbent and filter for biological22,25 or environmental applications26 because of their nanoscale size effect, high surface area, adjustable composition, and relatively low cost. In this paper, we designed an aged resorcinol-formaldehyde (RF) sol–gel ink for direct ink
writing of the microlattices. The suitable conditions and rheological behaviors for direct ink writing were got via the adjustment of the aging time for RF sol. Moreover, to improve the formability, the fresh microlattices were strengthened by HCl atmosphere, which acted as the surface catalysis. We use the nanostructure of the sol ink for 3D direct printing. But nanostructured ink has low viscosity and poor formability. To improve the formability, the fresh microlattices were strengthened by surface catalysis with HCl atmosphere. The printed sample itself had millimeterscale diffusion channels and a lot of micron-scale pores after
Data Loading...
