A B S T R A C TThe paradigm modifications in the metallic crystals from bulky to micro-size to nano-scale have resulted in excellent and amazing properties; which have been the remarkable interests in a wider range of applications. Particularly, Ag NPs have much attention owing to their distinctive optical, chemical, electrical and catalytic properties that can be tuned with surface nature, size, shapes, etc. and hence these crystals have been used in various fields such as catalysis, sensor, electronic components, antimicrobial agents in the health industry etc. Among them, Ag NPs based disinfectants have paid attention due to the practical applications in our daily life.

Complementary circuits based on organic electrochemical transistors (OECTs) are attractive for the development of inexpensive and disposable point-ofcare bioelectronic devices. Ambipolar OECTs, which employ a single channel material, could decrease the fabrication complexity and manufacturing costs of such circuits. An ideal channel material for ambipolar OECTs should be electrochemically stable in aqueous environments, afford facile ion insertion for both cations and anions, and also facilitate high and balanced electron and hole transport. In this study, triethylene glycol functionalized diketopyrrolopyrrole (DPP)-based polymer is proposed for the development of ambipolar OECTs. It is shown that DPP-based OECTs have a high and comparable figure of merit for both n-and p-type operations. Logic NOT, NAND, and NOR operations with corresponding complementary circuits constructed from identical DPP-based OECT devices are demonstrated. This study is an important step toward the development of sophisticated complementary metal-oxidesemiconductor-like logic circuits using single-component OECTs.

Nanostructured titanium dioxide (TiO2) has a potential platform for the removal of organic contaminants, but it has some limitations. To overcome these limitations, we devised a promising strategy in the present work, the heterostructures of TiO2 sensitized by molybdenum disulfide (MoS2) nanoflowers synthesized by the mechanochemical route and utilized as an efficient photocatalyst for methyl orange (MO) degradation. The surface of TiO2 sensitized by MoS2 was comprehensively characterized by X-ray diffraction (XRD), Raman spectroscopy, Fourier transform–infrared spectroscopy (FT–IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), UV–vis diffuse reflectance spectroscopy (UV–vis DRS), photoluminescence spectroscopy (PL), Brunauer–Emmett–Teller (BET) surface area, and thermogravimetric analysis (TGA). From XRD results, the optimized MoS2–TiO2 (5.0 wt %) nanocomposite showcases the lowest crystallite size of 14.79 nm than pristine TiO2 (20 nm). The FT–IR and XPS analyses of the MoS2–TiO2 nanocomposite exhibit the strong interaction between MoS2 and TiO2. The photocatalytic results show that sensitization of TiO2 by MoS2 drastically enhanced the photocatalytic activity of pristine TiO2. According to the obtained results, the optimal amount of MoS2 loading was assumed to be 5.0 wt %, which exhibited a 21% increment of MO photodegradation efficiency compared to pristine TiO2 under UV–vis light. The outline of the overall study describes the superior photocatalytic performance of 5.0 wt % MoS2–TiO2 nanocomposite which is ascribed to the delayed recombination by efficient charge transfer, high surface area, and elevated surface oxygen vacancies. The context of the obtained results designates that the sensitization of TiO2 with MoS2 is a very efficient nanomaterial for photocatalytic applications.

Redox-active conjugated polymers are an emerging class of organic charge storage materials for lithium-ion batteries. The electron conducting conjugated backbone linking the localized redox moieties enables fast electron transfer kinetics. Polymers with redox moieties that have fast redox kinetics and high redox potentials with respect to Li + /Li while being stable under electrochemical environments are ideal for energy storage applications. In this work, we propose diketopyrrolopyrrole (DPP) as a suitable redox moiety for realizing redox-active conjugated polymer-based Li-ion cathodes. Li-ion batteries using DPP-based polymers proposed in this work show stable cycling up to 1000 cycles, a high rate performance with ∼70% capacity retention at a C-rate of 500 C, and reasonably high potentials of ∼2.2 V vs Li + /Li. We also demonstrate that these polymers could potentially find applications as cathode materials in other ion insertion batteries such as, for example, Na-ion batteries. The results of our work set an encouraging precedent for designing versatile, high energy density, and long-life charge storage materials based on DPP-based redox-active conjugated polymers.

Resonance energy transfer (RET) can potentially improve device efficiencies of ternary blend organic solar cells (TBSCs). However, several parameters such as domain morphology, exciton lifetimes, energy and charge transfer influence...

Probing structural changes of a molecule induced by charge transfer is important for understanding the physicochemical properties of molecules and developing new electronic devices. Here, we interrogate the structural changes of a single diketopyrrolopyrrole (DPP) molecule induced by charge transport at a high bias using scanning tunneling microscope break junction (STM-BJ) techniques. Specifically, we demonstrate that application of a high bias increases the average nonresonant conductance of single Au−DPP−Au junctions. We infer from the increased conductance that resonant charge transport induces planarization of the molecular backbone. We further show that this conformational planarization is assisted by thermally activated junction reorganization. The planarization only occurs under specific electronic conditions, which we rationalize by ab initio calculations. These results emphasize the need for a comprehensive view of single-molecule junctions which includes both the electronic properties and structure of the molecules and the electrodes when designing electrically driven single-molecule motors.

Herein, a protocol strategy has been designed for the preparation of ternary silver nanoparticles-supported polyaniline multiwalled carbon nanotube (Ag NPs–PANI/MWCNT) nanocomposites with a chemical interaction for catalytic and antibacterial activity. The morphological study confirmed that Ag NPs were immobilized on the surface of PANI, and afterward, Ag NPs–PANI were mixed with the MWCNTs. The X-ray diffraction technique revealed the face-centered cubic structure of Ag NPs, and the X-ray photoelectron spectroscopy study revealed the chemical constituent and signature of π–π* and C–N interactions in the nanocomposites. The ternary Ag NPs–PANI/MWCNTs nanocomposites have the apparent rate of reaction (K app) as 5.4 × 10–3 s–1, higher than binary nanocomposites for catalytic reduction of 4-nitrophenol to 4-aminophenol at room temperature. Antibacterial activity of Ag NPs–PANI/MWCNT nanocomposites is higher against pathogenic bacteria. Thereafter, because of multifold applications of ternary nanocomposites, they have a broad scope in the field of environmental and healthcare sectors.

Organic solar cells (OSCs) fabricated from ternary blend thin film absorbers are designed to maximize the range of absorption in the solar spectrum and thus increase the short-circuit current density (J SC) of the device. Herein, we report OSCs formed with two different compositions of ternary blend thin films comprising two electron donors and one acceptor, namely, PTB7-Th/PCDTBT/IT4F and PTB7-Th/PBDB-T/IT4F. We evaluate the role of Förster resonance energy transfer (FRET) and blend morphology to achieve composition-dependent device performance. We observed ≥10% increment in J SC for both the ternary blends as compared to that for the PTB7-Th:IT4F binary blend, resulting in an enhanced power conversion efficiency (PCE) up to 10.34% for the PTB7-Th:PBDB-T:IT4F blend. We provide evidence that the two foremost parameters that control the PCE are blend morphology and FRET between donor components. The improved exciton generation rate for PCDTBT-based ternary blends was achieved, suggesting effective contribution of FRET toward enhanced device photocurrent, whereas the PBDB-T-based ternary blend excelled mainly due to suppressed carrier recombination as a result of favorable orientation with PTB7-Th/IT4F.