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Hydrogel membranes have emerged as promising candidates for solid-state supercapacitors (SSCs), overcoming limitations associated with traditional liquid electrolytes like leakage, thermal hazards, and flammability. However, single-network hydrogels often suffer from poor mechanical properties, making them inadequate for wearable applications. Herein, solution casting technique is used to develop a novel dual-crosslinked semi-interpenetrating polymer network (semi-IPN) hydrogel membrane through in-situ polymerisation of acrylic acid (AA) in a polyvinyl alcohol (PVA) matrix, followed by doping with KOH solution. By adjusting the composition between PVA and AA, the phase separation pathway is controlled, resulting in a homogeneously distributed porous architecture that enhances ion-conductive pathways. The hydrogel exhibited excellent properties, including high ionic conductivity (174 mS cm−1), considerable tensile strength (5 MPa), and significant elongation at break (460 %). Dielectric studies confirmed its significantly improved capacitive behaviour and low conductivity relaxation characteristics. Additionally, the resulting pseudocapacitor assembled with graphite-silvernanowire-polyaniline based composite electrode demonstrated a high specific capacitance (302 F g−1 at 0.2 A g−1) with outstanding capacity retention (75 % up to 500 cycles). Overall, the incorporation of this novel material provides great potential for high-performance SSC applications. [Display omitted] • Quasi-sold state semi-IPN membranes prepared via dual crosslinking method. • The homogeneously distributed porous novel architecture enhances ion transmission. • High ionic conductivity of 174 mS cm−1 achieved with >500 % KOH uptake. • The assembled pseudocapacitor gives a capacitance of 302 F g−1 at 0.2 A g−1. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbon dots (NCDs), exhibiting strong yellow emission in aqueous solution and solid matrices, have been utilized for fabricating heterostructure white electroluminescence devices. These devices consist of nitrogen-doped carbon dots as an emissive layer sandwiched between an organic hole transport layer (PEDOT:PSS) and an array of rutile TiO2 nanorods, acting as an electron transport layer. Under an applied forward bias of 5 V, the device exhibits broadband electroluminescence covering the wavelength range of 390–900 nm, resulting in pure white light emission characteristics at room temperature. The result demonstrates the successful fabrication of all solution-processed, low-cost, eco-friendly NCDs-based LEDs with CIE (Commission Internationale d'Éclairage) coordinate of (0.31, 0.34) and color rendering index (CRI) > 90, which are close to ideal white light emission characteristics. The device functionalities are achieved based on defect-related NIR emission from TiO2 nanorods array and visible emission from nitrogen-doped carbon dots. This result paves a new opportunity to develop low-cost, solution-processed nitrogen-doped carbon dots based on warm White light emitting diodes with high CRI for large-area display and lighting applications. [ABSTRACT FROM AUTHOR]

Hot carrier extraction is crucial for efficient solar energy harvesting, and lead halide perovskite nanocrystals (NCs) are potential candidates for photovoltaic and light-emitting applications. Therefore, swift extraction of hot carriers is an immediate requirement to improve the energy conversion efficiency, which need longer thermalization time. To address this issue, we synthesized nominally Cu-doped CsPbI3 NCs with enhanced structural and optical characteristics compared to undoped CsPbI3 NCs. We investigated the hot carrier dynamics in both the NCs at different fluences using ultrafast transient absorption spectroscopy. Interestingly, we observed very fast thermalization at higher fluences that indicated breaking of the phonon bottleneck. On the contrary, doped NCs preserved the effects and decayed over a longer period of time possibly due to increase in size and introduction of shallow trap states of Cu 3d and Cu 4s electrons in the conduction band, as computed using density functional theory. Notably, as the carrier–carrier interaction increased, we observed a dominating bandgap renormalization in the doped system compared to the undoped system. Overall, our studies improve the understanding of Cu doping in enhancing the hot carrier dynamics in perovskites and open possibilities for further investigation in the quantum phenomenon of these materials. [ABSTRACT FROM AUTHOR]

Although α‐CsPbI3 is regarded as an attractive optical luminophore, it is readily degraded to the optically inactive δ‐phase under ambient conditions. Here, we present a simple approach to revive degraded ("optically sick") α‐CsPbI3 through "medication" with thiol‐containing ligands. The effect of different types of thiols is systematically studied through optical spectroscopy. The structural reconstruction of degraded α‐CsPbI3 nanocrystals to cubic crystals in the presence of thiol‐containing ligands is visualized through high‐resolution transmission electron microscopy and supported by X‐ray diffraction analysis. We found that 1‐dodecanethiol (DSH) effectively revives degraded CsPbI3 and results in high immunity towards moisture and oxygen, hitherto unreported. DSH facilitates the passivation of surface defects and etching of degraded Cs4PbI6 phase, thus reverting them back to the cubic CsPbI3 phase, leading to enhanced PL and environmental stability. [ABSTRACT FROM AUTHOR]

Although α‐CsPbI3 is regarded as an attractive optical luminophore, it is readily degraded to the optically inactive δ‐phase under ambient conditions. Here, we present a simple approach to revive degraded ("optically sick") α‐CsPbI3 through "medication" with thiol‐containing ligands. The effect of different types of thiols is systematically studied through optical spectroscopy. The structural reconstruction of degraded α‐CsPbI3 nanocrystals to cubic crystals in the presence of thiol‐containing ligands is visualized through high‐resolution transmission electron microscopy and supported by X‐ray diffraction analysis. We found that 1‐dodecanethiol (DSH) effectively revives degraded CsPbI3 and results in high immunity towards moisture and oxygen, hitherto unreported. DSH facilitates the passivation of surface defects and etching of degraded Cs4PbI6 phase, thus reverting them back to the cubic CsPbI3 phase, leading to enhanced PL and environmental stability. [ABSTRACT FROM AUTHOR]

The utilization of lightweight materials that provide electromagnetic interference (EMI) shielding and impact attenuation is crucial for safeguarding fragile components in portable electronic devices. Although conductive foams have shown promise in providing lightweight electromagnetic interference (EMI) shielding, their potential for impact attenuation has yet to be thoroughly investigated. In this study, we fabricated a composite foam consisting of MXene and carboxylated nitrile rubber (MXene/XNBR) to achieve multifunctional properties such as electromagnetic interference (EMI) shielding and thermal management. The fabrication method involved the utilization of MXene nanoflakes and XNBR elastomer through a dual mixing approach, which encompassed both melt and solution mixing techniques. Utilizing a chemical blowing agent in integrating cellular structure inside a composite material has resulted in several advantageous properties, including reduced weight, enhanced processability, and improved thermal management capabilities. The MXene/XNBR foam composite exhibits a higher EMI shielding efficiency (SE) of − 30.9 dB. With a remarkably low density of 0.7 g.cm−3, this material exhibits a specific shielding effectiveness of 441.4 dB.cm2.g−1 with desirable stretchability and mechanical strength, positioning it as one of the most promising options for lightweight applications. Our multifunctional elastomeric foam composites collectively offer a significant pathway for developing high-performance foam material that exhibits exceptional shielding efficiency, thermal management, stretchability, and superior mechanical properties. [Display omitted] • Fabrication of lightweight microcellular MXene-loaded elastomeric foam composite. • Cellular structures reduces density of the MXene-loaded foam. • MXene enhanced foam composite's electrical conductivity. • MXene elastomeric foam shows absorption dominating EMI shielding effectiveness. [ABSTRACT FROM AUTHOR]

Due to the pressing need to mitigate current electromagnetic wave pollution (connecting to the 5 G era), lightweight, stretchable, thermally, and electrically conductive nanocomposite materials have attracted significant scientific interest. Herein, self-healable carboxylated nitrile butadiene elastomeric (XNBR) based nanocomposites were fabricated via sequential wet cum melt mixing technique utilizing multi-walled carbon nanotubes (MWCNTs). The metal-ligand complexes in the XNBR elastomer chain endow a reversible network that leads to self-healing ability. The higher aspect ratio of MWCNTs assists in constructing interconnected conductive pathways inside the XNBR matrix. The nanocomposite with MWCNTs (15 phr) provided an excellent EMI shielding effectiveness of − 27.4 dB, whereas the nanocomposite exhibited a thermal conductivity of 0.85 W.m−1. K−1. Interestingly, the interconnected networking pathway of MWCNTs in the XNBR matrix prepared a tunable analogical structure providing an absorption-dominant shielding mechanism. Under severe practical and environmental testing conditions, the nanocomposites showed a minute change in electromagnetic effectiveness, demonstrating their good performance for outdoor applications. These ultra-lightweight, self-healable, recyclable MWCNTs/ XNBR EMI shields are promising materials for next-generation super-stretchable and portable smart electronics. [Display omitted] • Elastomeric-based self-healable EMI radiation absorbing nanocomposites via continuous solution cum melt mixing technique. • The nanocomposites exhibited efficient self-healing behavior through the metal-to-ligand coordination bonds. • The nanocomposites with 15 phr MWCNTs offer an excellent EMI Shielding effectiveness and DC conductivity. • Negligible change in shielding efficiency after damage healing effect. [ABSTRACT FROM AUTHOR]