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Piezoelectric principle is one of the popular choices when it comes to mechanical energy recovery and conversion of energy into electrical energy which can be either stored or used straightaway. In general, ceramic-based piezoelectric materials like Lead Zirconate Titanate (PZT) had been the popular choice for piezoelectric devices even though they are brittle in nature and found to be toxic in long uses. At the same time, organic-based Polyvinylidene Fluoride (PVDF) and similar polymeric materials have been used in different applications with an offer of flexibility, lightweight and biocompatibility. One major factor dragging down the usage of organic materials in piezoelectric applications is their poor piezoelectric responses. In this work, authors are reporting the enhanced piezoelectric properties of nanofibers of PVDF in composite with copper nanoparticles and Multiwalled Carbon Nanotubes (MWCNTs). Fourier Transformation Infrared (FTIR) analysis has been carried out for nanofibers and was able to prove the higher beta phase conversion of PVDF in composite nanofibers when compared with pristine nanofibers. Composite nanofibers were later fabricated into a piezoelectric device with two electrodes and have shown a peak voltage of 6.78 V upon a drop test. As a proof of concept, the mentioned piezoelectric device was integrated into a shoe-based prototype where it has shown 18–20[Formula: see text]V energy harvesting upon walking at leisurely pace.

Cantilever-based piezoelectric has been the most preferred technique for energy harvesting and sensing application due to its simple design. The energy conversion efficiency has been continuously improved by exploring alternative cantilever geometries by increasing the stress distribution on the beam surface. In this paper, we have introduced half elliptical and full elliptical profile modification in the cantilever structure to improve and uniformly distribute the stress at the beam surface. Stress distribution characteristics of the modified cantilever beams were investigated and compared using finite element analysis. Based on the theoretical and finite element analysis, cantilever beams were fabricated using 3D print technology. Fabricated cantilever beams were then used to investigate the piezoelectric performances of polyvinylidene fluoride (PVDF) in composite of barium titanate (BaTiO3) nanoparticles in the form of electrospun composite nanofibers. FTIR analysis shows successful conversion of alpha phase to beta phase of PVDF and PVDF/BaTiO3 nanocomposites. During 6[Formula: see text]Hz cyclic actuating experiment, maximum voltage output of 0.15[Formula: see text]V and 1.5[Formula: see text]nA current output were observed. The concept was proposed to replace MEMS-based sensor in hand tremor quantification to assist Parkinson disease management.

Recent advances in bioprinting technology have been used to precisely dispense cell-laden biomaterials for the construction of complex 3D functional living tissues or artificial organs. Organ printing and biofabrication provides great potential for the freeform fabrication of 3D living organs using cellular spheroids, biocomposite nanofibers, or bioinks as building blocks for regenerative therapy. Vascularization is often identified as a main technological barrier for building 3D organs in tissue engineering. 3D printing of living tissues starts with potential support of biomaterials to maintain structural integrity and degradation of certain time periods after printing of the scaffolds. Biofabrication is the production of complex living and nonliving biological products from raw materials such as cells, molecules, ECM, and biomaterials. Generally, two basic methods are used for the fabrication of scaffolds such as conventional/traditional fabrication processes and advance fabrication processes for engineering organs. A wide range of polymers and biomaterials are used for the fabrication of scaffolds in tissue engineering applications. 3D additive manufacturing is advancing day-by-day; however, there are various critical challenging factors used for fabricating 3D scaffolds. This review is aimed at understanding the various scaffold fabrication techniques, types of polymers and biomaterials used for the fabrication processes, various fields of applications, and different challenges faced in their fabrication of scaffolds in regenerative therapy.