Electrospun nanofibrous scaffolds in neural tissue engineering provide an alternative approach for neural regeneration. Since the topography of a surface affects the microscopic behaviour of material; the creation of nanoscale surface features, which mimic the natural roughness of live tissue, on polymer surfaces can promote an appropriate cell growth and proliferation. In this research, a unique PLGA nanofibrous structure was fabricated without any post-electrospinning treatment. Scaffolds were prepared in two general groups: cylindrical and ribbon-shaped electrospun fibres, with smooth and rough (porous and grooved) surfaces. The experiments about nerve cell culture have demonstrated that the nanoroughness of PLGA electrospun scaffolds can increase the cell growing rate to 50 % in comparison with smooth and conventional electrospun scaffolds. SEM and AFM images and MTT assay results have shown that the roughened cylindrical scaffolds enhance the nerve growth and proliferation compared to smooth and ribbon-shaped nanofibrous scaffolds. A linear interaction has been found between cell proliferation and surface features. This helps to approximate MTT assay results by roughness parameters.

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Layered fabric systems with an electrospun nanofiber web layered onto a sandwich of woven fabric were developed to examine the feasibility of developing breathable barrier textile materials. Some parameters of nanofiber mats, including the time of electrospinning and the polymer solution concentration, were designed to change and barrier properties of specimens were compared. Air permeability, water vapor transmission, and water repellency (Bundesmann and hydrostatic pressure tests) were assessed as indications of comfort and barrier performance of different samples. These performances of layered nanofiber fabrics were compared with a well-known water repellent breathable multi-layered fabric (Gortex). Multi-layered electrospun nanofiber mats equipped fabric (MENMEF) showed better performance in windproof property than Gortex fabric. Also, water vapor permeability of MENMEF was in a range of normal woven sport and work clothing. Comparisons of barrier properties of MENMEF and the currently available PTFE coated materials showed that, those properties could be achieved by layered fabric systems with electrospun nanofiber mats.

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A novel hybrid piezoelectric structure based on electrospun PVDF NFs and vertically grown ZnO nanorods is presented as a promising nanogenerator to convert mechanical movement more efficiently into electricity for practical applications.

Hot-injection has become the most widespread method used for the synthesis of perovskite quantum dots (QDs) with enormous interest for application in optoelectronic devices.

Composite electrospun nanofibers mats, as a nanogenerator, were fabricated through one-step electrospinning method. The structure of fibers is composed of Poly(vinylidene fluoride), PVDF, as the matrix, and Zinc oxide (ZnO) nanoparticles; the nanocomposite were produced using electrospinning technique in order to have the benefit of piezoelectric properties and non-brittle behavior of ZnO and PVDF for the application in wearable electronic devices. Characteristics of these structures were evaluated by using Xray diffraction (XRD), Fourier Transform Infrared (FTIR), Differential Scanning Calorimetry (DSC) and Scanning Electron Microscopy (SEM). Impedance and the electrical conductivity of the fabricated composites were also evaluated by Keithley instruments. Electrical response of samples was measured using an impedance analyzer made in Aims Lab (http://aims.aut.ac.ir) at room temperature. Results showed that incorporating the ZnO nanoparticles into the PVDF nanofibers improved the piezoelectric properties of samples compared to PVDF samples. The electrical output of composite samples was improved as high as 1.1 V compared with 0.351 V for the pure PVDF samples. These results imply promising applications, as an enhancedefficiency energy-scavenging interface, for various wearable self-powered electrical devices and systems.

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