• Energy Research
• 2021-2025close

In this study, poly-lactic acid (PLA), nanohydroxyapatite (NHA), and graphene nanoplatelets (GNP) were blended to develop a nanocomposite material suitable for load-bearing bone implants with the potential for strain-sensing applications. The tensile properties and impact strength of the PLA-NHA nanocomposite were analyzed, as these are crucial biomechanical properties for load-bearing and strain-sensing applications. It was found that the impact strength decreased by 7.9% (0.05 wt% GNP) and 25.7% (0.1 wt% GNP) with increasing GNP loading compared to 0.01 wt% GNP. Besides, the biocompatibility of nanocomposites (PLA-NHA, PLA-mNHA, and PLA-mNHA-GNP) was evaluated through in-vitro analysis by attaching MG63 cells to the nanocomposites and observing their proliferation and differentiation over 7 and 21 days of incubation. The biocompatibility of the prepared nanocomposites was determined based on their ability to attach with MG63 cells, thus allowing the cells to proliferate and enhance their ability to differentiate. Results showed that the PLA-5wt%NHA nanocomposite provided better cell spreading compared to pure PLA, while the PLA-5wt%mNHA nanocomposite had the highest rate of cell proliferation. The biocompatibility of the nanocomposites was further confirmed by field emission scanning electron microscope (FESEM) imaging, MTT assays, and alkaline phosphatase (ALP) assays.

The treatment of wastewater is an expensive and energy-extensive practice that not only ensures the power generation requirements to sustain the current energy demands of an increasing human population but also aids in the subsequent removal of enormous quantities of wastewater that need to be treated within the environment. Thus, renewable energy source-based wastewater treatment is one of the recently developing techniques to overcome power generation and environmental contamination issues. In wastewater treatment, microbial fuel cell (MFC) technology has demonstrated a promising potential to evolve as a sustainable approach, with the simultaneous recovery of energy and nutrients to produce bioelectricity that harnesses the ability of electrogenic microbes to oxidize organic contaminants present in wastewater. Since traditional wastewater treatment has various limitations, sustainable implementations of MFCs might be a feasible option in wastewater treatment, green electricity production, biohydrogen synthesis, carbon sequestration, and environmentally sustainable sewage treatment. In MFCs, the electrochemical treatment mechanism is based on anodic oxidation and cathodic reduction reactions, which have been considerably improved by the last few decades of study. However, electricity production by MFCs remains a substantial problem for practical implementations owing to the difficulty in balancing yield with overall system upscaling. This review discusses the developments in MFC technologies, including improvements to their structural architecture, integration with different novel biocatalysts and biocathode, anode, and cathode materials, various microbial community interactions and substrates to be used, and the removal of contaminants. Furthermore, it focuses on providing critical insights and analyzing various types, processes, applications, challenges, and futuristic aspects of wastewater treatment-related MFCs and thus sustainable resource recovery. With appropriate planning and further studies, we look forward to the industrialization of MFCs in the near future, with the idea that this will lead to greener fuels and a cleaner environment for all of mankind.