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π‐Extended dithienopyrrolobenzothiadiazole‐isoindigo‐based conjugated polymers were synthesized and well characterized by using various analysis techniques like infrared (IR), 1H NMR, UV–Visible spectroscopy, thermogravimetric analysis, cyclic voltammetry analysis, and gel permeation chromatography. The bandgap of synthesized polymers, P‐1, P‐2, and P‐3, were determined to be 1.95, 1.91, and 1.93 eV, respectively. These polymers exhibited robust thermal stability up to 290°C. The highest occupied molecular orbital energy levels were below −5.0 eV for all polymers, while the lowest unoccupied molecular orbital energy levels ranged from −3.5 to −3.3 eV. The measured space charge limited current hole mobilities for polymers, P‐1, P‐2, and P‐3, were 1.02 ± 0.47 × 10−1, 1.17 ± 0.47 × 10−1, and 2.51 ± 0 0.47 × 10−2 cm2 V−1 s−1, respectively. [ABSTRACT FROM AUTHOR]

Mesoporous Co3O4/N‐PC in powder form was synthesized via a wet‐chemical approach, and the resulting material was deposited onto nickel foam as a substrate without the use of a binder. Prior to device fabrication, a thorough analysis of suitable and cost‐effective aqueous alkaline and neutral electrolytes was conducted. Electrolyte optimization was performed using Co3O4/N‐PC/NF electrode with Na2SO4, NaOH, LiOH, and KOH electrolytes. The supercapacitor performance of the binder‐free deposited materials was found to be superior in KOH electrolyte compared to other aqueous electrolytes at equal concentrations. Further optimization of the KOH electrolyte concentration was carried out to achieve the best electrochemical performance for the Co3O4/N‐PC/NF electrode. Electrochemical results demonstrated that the Co3O4/N‐PC/NF electrode performed well in 1 M KOH electrolyte, surpassing its performance at other concentrations. Subsequently, a solid‐state asymmetric device was fabricated, utilizing Co3O4/N‐PC, activated carbon, and a KOH+PVA gel as the cathode, anode, and electrolyte, respectively. The assembled asymmetric Co3O4/N‐PC/NF‐AC/NF device exhibited an energy density of 12.08 Wh kg−1 and a power density of 2500 W kg−1 within a potential window of 1.5 V. Impressively, after nearly 3000 continuous GCD cycles, the device showed negligible initial specific capacitance decay. The device was also successfully tested for powering the LED. [ABSTRACT FROM AUTHOR]

This research investigates the photoelectrochemical (PEC) water splitting capabilities of Cu-based metal–organic framework (MOF)-sensitized one-dimensional (1D) metal oxide nanostructures, specifically zinc oxide (ZnO) nanorod (NR)/multiwalled carbon nanotube (MWCNT) nanocomposites (ZC NCs). This study involves the synthesis of ZnO NRs as well as ZC NCs with varying content of MWCNTs (from 0.05 to 0.25 wt %) via the sol–gel technique, followed by a comprehensive analysis of their structural, optical, and surface properties. The incorporation of MWCNTs with ZnO revealed the enhanced optical and surface characteristics and high concentration of oxygen vacancies in ZC NCs as evidenced by electron spin resonance (ESR) analysis, contributing to improved PEC performance. Thereafter, binder-free thin films of the synthesized materials were deposited using the doctor-blade technique, and then, PEC water splitting performance was assessed through various electrochemical techniques. Herein, the PEC performance of ZC-0.1 NCs (with 0.1 wt % MWCNTs) was 4.5 times superior to that of bare ZnO NRs. Subsequently, the optimized ZC-0.1 NCs were further sensitized with CH3–Cu-BTC MOFs, forming ternary ZC-0.1/CH3–Cu-BTC NCs. For these ternary NCs, an impressive current density was observed (2.57 mA/cm2), nearly 9 times greater than that of pristine ZnO NRs (1.23 V) vs the reversible hydrogen electrode (RHE) and almost double that of ZC-0.1 NCs. Furthermore, the designed photoanode is stable over time, which was predicted and forecasted through the time series analysis (TSA) model. The higher PEC performance for ternary NCs was justified through surface topography, morphological, and contact angle studies to analyze the surface nature and its hydrophilicity. Hence, the present work demonstrates the systematic roadmap for a PEC water splitting study using valuable insights for the design and optimization of nanostructured metal oxides, photoactive organic moieties, and their composites. [ABSTRACT FROM AUTHOR]

The present research endeavor is focused on designing tungsten(VI) ion-doped TiO2/rGO nanocomposites (TR NCs) via a single-step in situ wet chemical route for Co2+/Co3+-based PEO–PEG polymer gel electrolyte-assisted D–π–A carbazole dye (SK3) sensitized solar cells (DSSCs). After the synthesis of the desired W@TiO2/rGO (WTR) NCs, their physicochemical (viz., optoelectrical, structural, morphological, electrochemical, etc.) properties are studied. BET reveals a higher surface area with improved pore volumes up to 344.04 m2 g−1 and 0.918 cm3 g−1, respectively, for W0.020@Ti0.980/rGO (WTR-2) NCs as compared to others. The doctor blade technique is deployed for depositing photoanodes. EIS and M–S analysis showed improved photogenerated charge transfer and a higher carrier density, respectively, for WTR-2 NCs. Thereafter, WTR-2 NCs were further sensitized with SK3 dye and sandwiched with a Pt-counter electrode for making DSSCs, and then photovoltaic performance was studied and compared to that of bare TiO2 NPs under an AM 1.5 solar simulator. The WTR-2 NC-based DSSCs exhibited the highest conversion efficiency (η) of 6.95%, which is 3.7 and 5.2 times greater than that of TR NC-based (1.84%) and bare TiO2 NP-based (1.32%) DSSCs, respectively. Hence, the present investigation validates the effectual photovoltaic performance of the DSSCs comprising TiO2 NP-based hybrids and SK3 dye and the utilization of Co2+/Co3+-based PEO–PEG polymer gel electrolyte. [ABSTRACT FROM AUTHOR]

As a part of our ongoing research, we have synthesized a new fluorescence probe, p-C4A, based on a calix[4]arene substituted with 4-aminoquinoline moieties with amide linkages. p-C4A can selectively recognize Li+ and PO43− ions and has been characterized via an emission study, an absorption study, ESI-MS spectroscopy, a 1H NMR study and cyclic voltammetry. The fluorescence sensor p-C4A can operate over a concentration range of 5–170 nM for Li+ sensing and 5–80 nM for PO43− sensing. The R2 values obtained for the sensing of Li+ and PO43− ions are 0.9962 and 0.9911, respectively. p-C4A demonstrates a minimum detection limit of 6.15 nM for Li+ and 9.0 nM for PO43−. The quantum yields of p-C4A as its Li+ and PO43− ion complexes were found to be 0.014 and 0.27, respectively. Herein, we report an easy-to-use, low-cost, disposable, paper-based, fluorescent, wax-printed device for the rapid chemical screening of Li+ and PO43−. This device can be used as a quick, portable, multiple-test panel that is simple, lightweight, and disposable. Moreover, in order to assess its analytical applicability, the prepared sensor was successfully used for the determination of Li+ and PO43− from wastewater samples, validating the proposed ion recovery method with 96–99% recovery rates. [ABSTRACT FROM AUTHOR]