This paper primarily focuses on areas within non-Newtonian fluid mechanics that remain underexplored or inadequately investigated. It highlights research domains that have not received sufficient attention or detailed study, while also considering the emergence of new areas unexplored by recent scientific and technological advancements. For example, this study explores research directions and innovative modeling and theoretical strategies for understanding fluid dynamics in complex, deformable, and branched flow systems across multiple scales. The elastoviscoplastic behavior of fluids under external forcing is used to model droplet spreading, coalescence, and filtering over porous and soft substrates. Wall slip and junction resistance effects of the flow are in a tree-like structure. The study also highlights and explores research directions in the flow physics of non-Newtonian fluids that exhibit odd viscosity and odd elasticity, focusing on their unconventional stress–strain responses and the resulting unique flow behaviors. The objective of this paper is to raise awareness about these relatively neglected or unexplored areas of research, encouraging researchers to put efforts toward these promising domains. By doing so, they can contribute to advancing the field in ways that diverge from which have already been sufficiently explored and may lead to breakthroughs and novel discoveries by generalizing the existing laws or creating new models and laws. Moreover, addressing these under-explored areas could have far-reaching implications for both theoretical and practical applications in non-Newtonian fluid mechanics. Investigating these areas more deeply could uncover new insights, enhance existing models, and drive forward technological advancements that were previously overlooked. In addition, this paper will briefly discuss the potential introduction of novel tools, techniques, and methodologies that could be applied to these research areas, as well as to the broader field of non-Newtonian fluid mechanics. Furthermore, we also discuss the current and upcoming applications using non-Newtonian fluids. These innovations could open up new avenues of exploration and help overcome some of the existing limitations in past and current research.

Electrode materials comprising SnO ₂ quantum dots embedded within ZnO hexagonal prisms were successfully synthesized for building cost-effective energy-storage devices. Extensive structural and functional characterizations were performed to assess the electrochemical performance of the electrodes. SEM–EDS results confirm a uniform distribution of SnO ₂ quantum dots across ZnO. The integration of SnO ₂ quantum dots with ZnO hexagonal prisms markedly improved the electrochemical behavior. The analysis of electrode functionality conducted in a 3 M KOH electrolyte revealed specific capacitances of 949.26 and 700.68 F g⁻ ¹ for SnO ₂ @ZnO and ZnO electrodes, respectively, under a current density of 2 A g⁻ ¹ . After undergoing 5,000 cycles at a current density of 15 A g⁻ ¹ , the SnO ₂ @ZnO and ZnO electrodes displayed impressive cycling stability, maintaining specific capacitance retention rates of 89.9 and 92.2%, respectively. Additionally, a symmetric supercapacitor (SSC) device constructed using the SnO ₂ @ZnO electrode showcased exceptional performance, exhibiting a specific capacitance of 83 F g⁻ ¹ at 1.2 A g⁻ ¹ . Impressive power and energy densities were achieved by the device, with values reaching 2,808 and 70.2 W kg⁻ ¹ , respectively. Notably, the SnO ₂ @ZnO SSC device maintained a capacity preservation of 75% throughout 5,000 galvanostatic charge–discharge sequences. The outcomes highlight the potential of SnO ₂ @ZnO hexagonal prisms as candidates for energy-storage applications, offering scalability and cost-effectiveness. The proposed approach enhances the electrochemical performance while ensuring affordability, facilitating the creation of effective and financially feasible energy storage solutions.

Supercapacitors have garnered substantial interest owing to their capacity to deliver power effectively for short-term applications. However, current supercapacitors suffer from limited stability and low-capacity storage. Metal-organic frameworks (MOFs) have emerged as a promising solution due to their high surface area and abundant active redox sites. MOF-based electrodes combined with aqueous based electrolytes have shown potential to enhance supercapacitor performance. While there is limited literature on MIL-101(Fe) MOF-based electrodes, a comparative study was conducted to investigate the supercapacitor performance of MIL-101(Fe) electrodes synthesized using hydrothermal and microwave-assisted processes. Processing parameters, such as the method used, alter the microstructure, morphology, and uniformity of supramolecular chemistry, impacting electrochemical characteristics. This study aimed to determine the active redox reactions, chemical stability, surface area, adsorption characteristics, and electrochemical characteristics of the electrodes. The electrodes from hydrothermal synthesis [MF(ht)] exhibited excellent electrochemical activity in comparison to the microwave-assisted [MF(m)] electrodes in the three-electrode configuration. At a high current density of 7 A/g, the MF(ht) electrode displayed a remarkable specific capacitance of 775.6 F/g and a good cyclic stability (82% @ 10 A/g) after 5000 galvanostatic charge–discharge cycles. At a current density of 1 A/g, the two-electrode configuration of MF(ht) yielded a high energy density of 74.7 Wh/kg at a power density of 2160 W/kg and a decent cyclic stability after 5000 cycles. The results suggest that the MF(ht) electrodes possess remarkable electrochemical properties that make them a promising candidate for advanced applications in energy storage.