Nano and Micro Ceramic Membranes from Degradable Templates

Abstract

The nano/microstructures with highly porous surface area have attracted tremendous attention, particularly the synthesis and tailoring of porous and hollow materials of high performance. In this paper, an easy method of cost-effective synthesis of hollow ceramic fiber membranes based on Hydroxyapatite, TiO 2 and ZrO 2 stabilized with Yttrium, is proposed by a single chemical route (polymeric precursor method) and a bio-template route (easy to degrade in thermal conditions). This article reports also the ZrTiO 4 nanowires synthesis on a silicon (100) wafer in a single step deposition/ thermal treatment. Template-directed membrane synthesis strategy was associated to the polymeric precursor route and spin-coating deposition technique. In this method, ZrTiO 4 nanowire ceramic were synthesized by spin-coating thermal treatment technique using polycarbonate membrane as a template. According to the results, after heat-treatment by the template removal, the ZrTiO 4 nanowire consists of uniformly deposited crystalline and porous nanoparticles that exhibited a higher surface area and a higher porosity. The polycrystalline nanowires were obtained at by thermal treatment with diameter in the range of 60-100 nm. Photoluminescence spectra were collected for fiber at room temperature. These characterizations demonstrate the morphology of structures formed, showing its hollow and porous conformation, suitable applications to advanced reinforced or device component material.

Study of biomorphic calcium deficient hydroxyapatite fibres derived from a natural Harakeke (Phormium tenax) leaf fibre template

“…A number of studies has reported the formation of a bone-like apatite layer on porous HAp material surfaces in vitro and stimulation of new bone formation and growth into the interconnected porosity of a scaffold/implant [16][17][18]. To synthesise HAp with a natural porous network and to imitate the porous structure of spongy bone, scientists have tried different techniques such as polymeric sponge replication [19], animal bone conversion [20], electrospinning [21], phase-separation [22], freezedrying [23], and gel-casting techniques [24], however templated synthesis of hydroxyapatite based materials has attracted considerable interest in the last ten years [25][26][27]. Research on apatitic ('hydroxyapatite'-like) mineralisation from super-saturated calcium phosphate solutions has led to the view that amorphous calcium phosphate (ACP) is a precursor phase of crystalline hydroxyapatite i.e.…”