Tsvetozar Tsanev; Mariya Aleksandrova; Boriana Tzaneva; Valentin Videkov
Abstract
This paper is devoted to the approach for nanostructuring piezoelectric materials to enhance their electrical signal producing ability from a small area of mechanical activation for potential application as energy harvesting. The geometrical structuring of the piezoelectric material leads to higher piezoelectric ...
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This paper is devoted to the approach for nanostructuring piezoelectric materials to enhance their electrical signal producing ability from a small area of mechanical activation for potential application as energy harvesting. The geometrical structuring of the piezoelectric material leads to higher piezoelectric voltage per unit volume in comparison with a non-structured thin film. Template properties of porous anodic aluminium oxide (AAO) allow this approach. AAO layers with a variety of pore diameters (from 80nm to 100nm) were produced without overheating degradation of the substrates. The thickness of the studied layer was 19 1µm. It was realized sputtering of potassium niobate deposition into AAO to a maximum penetration of piezoelectric material into the pores. The obtained final structure was observed by scanning electron microscopy and Energy Dispersive X-Ray spectroscopy. The registered piezoelectric effect reaches to 454 mV for the reanodized membrane with pores widening. In this work, we continue to explore and further development of our previous research for template-assisted growth in porous aluminium oxide.
Ryan Chang Tseng; Ching-Wen Li; Gou-Jen Wang
Abstract
The extensive use of iron oxide nanomaterials in biomedical applications has prompted the development of a novel substrate for evaluating cell behaviour. This study examines the fabrication of tuneable length iron oxide pillar arrays using the porous nanochannels of anodic aluminium oxide membranes, ...
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The extensive use of iron oxide nanomaterials in biomedical applications has prompted the development of a novel substrate for evaluating cell behaviour. This study examines the fabrication of tuneable length iron oxide pillar arrays using the porous nanochannels of anodic aluminium oxide membranes, and evaluates the biocompatibility of the substrate. The electroformed iron pillars were found to conform to the template channels with slightly larger iron oxide pillar diameters, due to the presence of an oxide shell. The biocompatibility was then confirmed with WST-1 proliferation and viability assay of cultured KT98 murine neural/progenitor stem cells on the surface of the pillar array; with no significant difference observed between viable cells after seven days of culture on iron oxide pillars, flat iron oxide, and tissue culture polystyrene. The physical properties of the pillar arrays were linked to the adhesion and spreading of the cells, and found that cells cultured on the pillar arrays had reduced spreading in comparison to tissue culture polystyrene control. In addition, it was found that protein expression was unaffected by culture on iron oxide substrates. The results of this study indicate that iron oxide pillar arrays are suitable to extended cell studies.
P. Venkatesu; K. Ravichandran
Abstract
Nano-polycrystalline samples of cadmium sulphide doped with 0, 2, 4, 6, 8 and 10 atomic % of Mn were prepared by a template based chemical route. The presence of thiophenol as template on the surface of the samples has been detected with FTIR technique. Particle sizes of 15-50 nm range, hexagonal structure ...
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Nano-polycrystalline samples of cadmium sulphide doped with 0, 2, 4, 6, 8 and 10 atomic % of Mn were prepared by a template based chemical route. The presence of thiophenol as template on the surface of the samples has been detected with FTIR technique. Particle sizes of 15-50 nm range, hexagonal structure and polycrystalline nature of the samples have been identified through SEM and TEM techniques. Surface states in the band gap region of the samples confirmed by PL study also revealed that the size of the particles is in the nano range. The low temperature magnetization study suggested the 10 at.% Mn doped sample might be in a re-entrant-spin glass phase at 77 K.