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Research on wearable sensing technologies has been gaining considerable attention in the development of portable bio-monitoring devices for personal health. However, traditional energy storage systems with defined size and shape have inherent limitations in satisfying the performance requirements for flexible electronics. To overcome this constraint, three different configurations of flexible asymmetric supercapacitor (FASC) are fabricated on polyester/cellulose blend (PCB) cloth substrate using Ti 3 C 2 nanosheet (NS) and 1T WS 2 NS as electrodes, and aqueous pluronic gel as an electrolyte. Benefiting from the 2D material electrodes, the interdigitated FASC configuration exhibits excellent performance, flexibility, cyclic stability, wearability and can be configured into multiple units and shapes, which far exceed that exhibited by the textile-based FASC. Furthermore, the arbitrary ("AFN") and sandwich ("FLOWER") configurations Ti 3 C 2 NS/1T WS 2 NS FASC can be assembled directly on a PCB cloth substrate, thereby offering good structural integrity coupled with ease of assembly into integrated circuits of different shapes. More specifically, a lightweight, flexible, and wearable bio-monitoring system is developed by integrating force sensing device with interdigitated FASC, which can be used to monitor the physical status of human body during various activities. A potential application of this system in healthcare is successfully demonstrated and discussed.

Hydrothermally grown one-dimensional ZnO nanowire (1D ZnO NW) and a newly synthesized metal-free, D-π-A type, carbazole dye (SK1) sensitizer-based photovoltaic device with a power conversion efficiency (PCE) of more than 5% have been demonstrated by employing the cobalt tris(2,2'-bipyridyl) redox shuttle. A short-circuit current density (Jsc) of ∼12.0 mA/cm(2), an open-circuit voltage (Voc) of ∼719 mV, and a fill factor (FF) of ∼65% have been afforded by the 1D ZnO NW-based dye-sensitized solar cell (DSSC) incorporating [Co(bpy)3](3+/2+) complex as the one-electron redox mediator. In contrast, the identical DSSC with traditional I3(-)/I(-) electrolyte has shown a Jsc ≈ 12.2 mA/cm(2), a Voc ≈ 629 mV, and a FF ≈ 62%, yielding a PCE of ∼4.7%. The persuasive role of the inherent superior electron transport property of 1D ZnO NWs in enhancing the device efficiency is evidenced from the impoverished performance of the DSSCs with photoanodes fabricated using ZnO nanoparticles (NPs). The DSSCs having ZnO NP-based photoanodes have achieved the PCEs of ∼3.6% and ∼3.2% using cobalt- and iodine-based redox electrolytes, respectively. The electronic interactions between the SK1 sensitizer and ZnO (NWs and NPs) to induce the photogenerated charge transfer from SK1 to the conduction band (CB) of ZnO are evidenced from the significant quenching of photoluminescence and exciton lifetime decay of SK1, when it is anchored onto the ZnO architectures. The energetics of the SK1 dye molecule are estimated by combining the spectroscopic and electrochemical techniques. The electronic distributions of SK1 dye molecule in its HOMO and LUMO energy levels are interpreted using density functional theory (DFT)-based calculations. The electron donor-π linker-acceptor (D-π-A) configuration of SK1 dye provides an intramolecular charge transfer within the molecule, prompting the electron migration from the carbazole donor to cyanoacrylic acceptor moiety via the oligo-phenylenevinylene linker group. The D-π-A-mediated electron movement witnesses the favorable photoexcited electron transfer from the LUMO of SK1 dye to the CB of ZnO through the carboxyl anchoring group.

DSSCs with >9% PCE based on a new D–π–A dye (SK3) having carbazole as a donor, vinylene-phenylene (π-bridge) and cyanoacrylic acid as electron withdrawing–injecting as well as anchoring groups are reported.

Efficient electron donors, phenothiazine (PTZ)/phenoxazine (POZ) substituted imidazolium (IMI) and benzimidazolium (BIMI) iodide solid organic ionic conductors (SOICs) possessing good thermal stability and high conductivity are synthesized and used as electrolytes in solid state dye solar cell (ss-DSSC).

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Nano/micromotor technology is evolving as an effective method for water treatment applications in comparison to existing static mechanisms. The dynamic nature of the nano/micromotor particles enable faster mass transport and a uniform mixing ensuring an improved pollutant degradation and removal. Here we develop thermosensitive magnetic nanorobots (TM nanorobots) consisting of a pluronic tri-block copolymer (PTBC) that functions as hands for pollutant removal. These TM nanorobots are incorporated with iron oxide (Fe3O4) nanoparticles as an active material to enable magnetic propulsion. The pickup and disposal of toxic pollutants are monitored by intermicellar agglomeration and separation of PTBC at different temperatures. The as-prepared TM nanorobots show excellent arsenic and atrazine removal efficiency. Furthermore, the adsorbed toxic contaminants on the TM nanorobots can be disposed by a simple cooling process and exhibit good recovery retention after multiple reuse cycles. This combination of temperature sensitive aggregation/separation coupled with magnetic propulsion opens a plethora of opportunities in the applicability of nanorobots in water treatment and targeted pollutant removal approaches.

Owing to the rise of miniaturized wearable electronic devices in the last decade, significant demands have arisen to obtain high-performance flexible supercapacitors (FSCs). Recently, a lot of research has been focused on developing smart components of FSCs and integrating them into new device configurations. In this work, FSCs based on a Ti3C2 nanosheet (NS) and an organic ionic conductor (OIC)-induced hydrogel as the electrode and the electrolyte, respectively, were used. The FSCs fabricated have three different configurations (sandwich, twisted fiber, and interdigitated) and a comparative study of their electrochemical performance was investigated in terms of cycle stability, bending stability, power density, and energy density. Finally, the experimental validation of practical application was conducted, which suggested excellent electrochemical stability of Ti3C2 NS FSCs for driven commercial electronic gadgets. This study presents mechanically robust, lightweight, high-performance FSCs, which can be assembled in different configurations for powering wearable electronic devices.