Observation of anomalously large Nernst effects in conducting polymers.

As a fundamental thermoelectric phenomenon in many solid-state materials, the Nernst effect has yet to be observed in conducting polymers. This knowledge could provide important insight into their elusive mechanism, which are crucial for flexible optoelectronic and thermoelectric applications. However, within the Landau's Fermi-liquid picture, the Nernst coefficient has demonstrated to be proportional to the charge mobility, and thus should be negligible in less ordered polymers with inherent low mobility.

Structural Modifications for Tuning Performance and Operational Modes in n-Type Organic Electrochemical Transistors.

Organic mixed ionic-electronic conductors (OMIECs) are crucial in defining the operational modes and performance of organic electrochemical transistors (OECTs). However, studies on the design and structure-performance correlations of small-molecule n-type OMIECs remain scarce. Herein, we designed and synthesized a series of naphthalene diimide (NDI)-based n-type small molecules by extending π-conjugation and increasing the number of electron-withdrawing groups, achieving performance optimization and even changes in operational modes through structural regulations.

Lateral intercalation-assisted ionic transport towards high-performance organic electrochemical transistor.

Efficiently mixed conduction between ionic and electronic charges stands to revolutionize the studies in organic electrochemical transistors (OECTs). However, inefficient ion transport due to the long-range injection and migration process in the bulk film presents challenges for enhancing the steady and transient performance of OECTs. In this work, we proposed a lateral intercalation-assisted ion transport strategy to assist volumetric ion charging, by introducing a striped microstructure in the conductive channel.

A Comparatively Low Cost, Easy-To-Fabricate, and Environmentally Friendly PVDF/Garnet Composite Solid Electrolyte for Use in Lithium Metal Cells Paired with Lithium Iron Phosphate and Silicon.

Solid electrolytes may be the answer to overcome many obstacles in developing the next generation of renewable batteries. A novel composite solid electrolyte (CSE) composed of a poly(vinylidene fluoride) (PVDF) base with an active nanofiber filler of aluminum-doped garnet Li ceramic, Li salt lithium -(trifluoromethanesulfonyl)imide (LiTFSI), Li fluoride (LiF) stabilizing additive, and plasticizer sulfolane was fabricated. In a Li|CSE|LFP cell with this CSE, a high capacity of 168 mAh g with a retention of 98% after 200 cycles was obtained, representing the best performance to date of a solid electrolyte with a PVDF base and a garnet inorganic filler.

Morphology-Controlled Ion Transport in Mixed-Orientation Polymers.

Advancing iontronics with precisely controlled ion transport is fundamentally important to bridge external organic electronics with the biosystem. This long-standing goal, however, is thus far limited by the trade-off between the active ion electromigration and idle diffusion leakage in the (semi)crystalline film. Here, we presented a mixed-orientation strategy by blending a conjugated polymer, allowing for simultaneously high ion electromigration efficiency and low leakage.

Nanoscale doping of polymeric semiconductors with confined electrochemical ion implantation.

Nanoresolved doping of polymeric semiconductors can overcome scaling limitations to create highly integrated flexible electronics, but remains a fundamental challenge due to isotropic diffusion of the dopants. Here we report a general methodology for achieving nanoscale ion-implantation-like electrochemical doping of polymeric semiconductors. This approach involves confining counterion electromigration within a glassy electrolyte composed of room-temperature ionic liquids and high-glass-transition-temperature insulating polymers.

Achieving Stable Lithium Metal Anode at 50 mA cm Current Density by LiCl Enriched SEI.

Lithium metal batteries are intensively studied due to the potential to bring up breakthroughs in high energy density devices. However, the inevitable growth of dendrites will cause the rapid failure of battery especially under high current density. Herein, the utilization of tetrachloroethylene (C Cl ) is reported as the electrolyte additive to induce the formation of the LiCl-rich solid electrolyte interphase (SEI).

Improving the Performance of Red Organic Light-Emitting Transistors by Utilizing a High- Organic/Inorganic Bilayer Dielectric.

Integration of electrical switching and light emission in a single unit makes organic light-emitting transistors (OLETs) highly promising multifunctional devices for next-generation active-matrix flat-panel displays and related applications. Here, high-performance red OLETs are fabricated in a multilayer configuration that incorporates a zirconia (ZrO)/cross-linked poly(vinyl alcohol) (C-PVA) bilayer as a dielectric. The developed organic/inorganic bilayer dielectric renders high dielectric constant as well as improved dielectric/semiconductor interface quality, contributing to enhanced carrier mobility and high current density.

Identifying the Molecular Origins of Green BN-TADF Material Degradation and Device Stability via in situ Raman Spectroscopy.

There is little investigation into the impact of molecular conformation on device efficiency and degradation of boron-nitrogen thermally activated delayed fluorescence emitters (BN-TADF). Herein, three highly-efficient green BN-TADF emitters have been designed to unveil the impact of peripheral phenyl groups on device efficiencies and lifetimes. Compared to BN-PhOH with the lowest EQE of 19 %, BN-PhOCH and BN-PhN(CH ) have achieved strongly enhanced EQE of 25.

Highly Foldable, Super-Sensitive, and Transparent Nanocellulose/Ceramic/Polymer Cover Windows for Flexible OLED Displays.

Polymer cover windows are important components of flexible OLED displays but they easily generate wrinkles because of their weak folding resistance. Increasing the polymer thickness can improve the folding resistance but it decreases the touch sensitivity. Thus, fabricating highly foldable and supersensitive polymer cover windows is still challenging.

Narrowband Deep-Blue Multi-Resonance Induced Thermally Activated Delayed Fluorescence: Insights from the Theoretical Molecular Design.

Multi-resonance thermal activated delayed fluorescence (MR-TADF) has been promising with large oscillator strength and narrow full width at half maxima of luminescence, overcoming the compromise of emission intensity and energy criteria of traditional charge transfer TADF frameworks. However, there are still limited theoretical investigations on the excitation mechanism and systematic molecular manipulation of MR-TADF structures. We systematically study the highly localized excitation (LE) characteristics based on typical blue boron-nitrogen (BN) MR-TADF emitters and prove the potential triangular core with theoretical approaches.

Highly Soluble and Stable, High Release Rate Nanocellulose Codrug Delivery System of Curcumin and AuNPs for Dual Chemo-Photothermal Therapy.

As a natural antitumor drug, curcumin (CUR) has received increasing attention from researchers and patients due to its various medicinal properties. However, currently CUR is still restricted due to its low and stand-alone therapeutic effects that seriously limit its clinical application. Here, by using cellulose nanocrystals (CNCs) as a nanocarrier to load CUR and AuNPs simultaneously, we developed a hybrid nanoparticle as a codrug delivery system to enhance the low and stand-alone therapeutic effects of CUR.

Flexible, transparent and tough silver nanowire/nanocellulose electrodes for flexible touch screen panels.

Flexible touch screen panel (f-TSP) has been emerging recently and metallic nanowire transparent conductive electrodes (TCEs) are its key components. However, most metallic nanowire (MNW) TCEs suffer from weak bonding strength between metal nanowire electrode layers and polymer substrates, which causes delamination of TCEs and produces serious declines in durability of f-TSPs. Here, we introduce AgS bonding and develop tough and strong electrode-substrate bonded MNW TCEs, which can enhance durability of f-TSPs significantly.

Disintegrable, transparent and mechanically robust high-performance antimony tin oxide/nanocellulose/polyvinyl alcohol thermal insulation films.

Polymer-based thermal insulation films are widely utilized to reduce the influence of solar radiation. However, current thermal insulation films face several challenges from poor thermal insulation performance and severe environmental pollution, which are caused by the non-disintegratability of polymer substrates. Here, cellulose nanofiber (CNF)/antimony tin oxide (ATO) hybrid films with and without polyvinyl alcohol (PVA) are presented and they can be used as window thermal barrier films and personal thermal management textiles.

Record-Low Subthreshold-Swing Negative-Capacitance 2D Field-Effect Transistors.

Power consumption is one of the most challenging bottlenecks for complementary metal-oxide-semiconductor integration. Negative-capacitance field-effect transistors (NC-FETs) offer a promising platform to break the thermionic limit defined by the Boltzmann tyranny and architect energy-efficient devices. However, it is a great challenge to achieving ultralow-subthreshold-swing (SS) (10 mV dec ) and small-hysteresis NC-FETs simultaneously at room temperature, which has only been reported using the hafnium zirconium oxide system.

Highly Thermally Stable, Green Solvent Disintegrable, and Recyclable Polymer Substrates for Flexible Electronics.

Flexible electronics require its substrate to have adequate thermal stability, but current thermally stable polymer substrates are difficult to be disintegrated and recycled; hence, generate enormous electronic solid waste. Here, a thermally stable and green solvent-disintegrable polymer substrate is developed for flexible electronics to promote their recyclability and reduce solid waste generation. Thanks to the proper design of rigid backbones and rational adjustments of polar and bulky side groups, the polymer substrate exhibits excellent thermal and mechanical properties with thermal decomposition temperature (T ) of 430 °C, upper operating temperature of over 300 °C, coefficient of thermal expansion of 48 ppm K , tensile strength of 103 MPa, and elastic modulus of 2.

High-performance near-infrared Schottky-photodetector based graphene/InS van der Waals heterostructures.

Two-dimensional (2D) β-InS is a natural defective n-type semiconductor attracting considerable interest for its excellent photoelectronic performance. However, β-InS based photodetectors exhibited a weak near-infrared photoresponse compared to visible wavelength in past reports. In this work, high-quality 2D β-InS nanosheets were prepared by a space-confined chemical vapor deposition (CVD) method.

Ultrabroadband Photodetectors up to 10.6 µm Based on 2D Fe O Nanosheets.

The ultrabroadband spectrum detection from ultraviolet (UV) to long-wavelength infrared (LWIR) is promising for diversified optoelectronic applications of imaging, sensing, and communication. However, the current LWIR-detecting devices suffer from low photoresponsivity, high cost, and cryogenic environment. Herein, a high-performance ultrabroadband photodetector is demonstrated with detecting range from UV to LWIR based on air-stable nonlayered ultrathin Fe O nanosheets synthesized via a space-confined chemical vapor deposition (CVD) method.

Multicolored Cathodically Coloring Electrochromism and Electrofluorochromism in Regioisomeric Star-Shaped Carbazole Dibenzofurans.

In this work, a series of fluorescent cathodically coloring electrochromic (EC) small molecules , , and with 3,5-di(9-carbazol-9-yl)benzene (DCz) linked to dibenzofuran (DBF) at different substitutional positions were synthesized and fully characterized. These compounds are electroactive and undergo quasi-reversible two-step single-electron reduction generating radical anions and dianions. The absorptions of , , and in the neutral states lie in the UV region (λ ≈ 350 nm), showing high transparency, while the absorption of their reduced states can be largely tuned across the visible region through driving voltage and substitutional positions.

Trifluoromethyl Group-Modified Non-Fullerene Acceptor toward Improved Power Conversion Efficiency over 13% in Polymer Solar Cells.

Herein, we report a new molecule structure modification strategy for non-fullerene small-molecule electron acceptors (NFAs) for solar cells through trifluoromethylation of end-capping groups. The synthesized trifluoromethylated acceptor ITCF3 exhibits narrower band gap, stronger light absorption, lower molecular energy levels, and better electron transport property compared to the reference NFA without the trifluoromethyl group (ITIC). Bulk heterojunction solar cells based on ITCF3 combined with the PM6 polymer donor exhibit a significantly improved power conversion efficiency of 13.

Self-Confined Growth of Ultrathin 2D Nonlayered Wide-Bandgap Semiconductor CuBr Flakes.

2D planar structures of nonlayered wide-bandgap semiconductors enable distinguished electronic properties, desirable short wavelength emission, and facile construction of 2D heterojunction without lattice match. However, the growth of ultrathin 2D nonlayered materials is limited by their strong covalent bonded nature. Herein, the synthesis of ultrathin 2D nonlayered CuBr nanosheets with a thickness of about 0.

SnS hollow nanofibers as anode materials for sodium-ion batteries with high capacity and ultra-long cycling stability.

In this study, a novel anode material of SnS hollow nanofibers (SnS HNFs) was rationally synthesized by a facile process and demonstrated to be a promising anode candidate for sodium-ion batteries. The synergetic effect of unique hollow and porous microstructures of SnS HNFs led to high capacity and ultra-long cycling stability.

Electrospun Kraft Lignin/Cellulose Acetate-Derived Nanocarbon Network as an Anode for High-Performance Sodium-Ion Batteries.

An innovative nanocarbon network material was synthesized from electrospun kraft lignin and cellulose acetate blend nanofibers after carbonization at 1000 °C in a nitrogen atmosphere, and its electrochemical performance was evaluated as an anode material in sodium-ion batteries. Apart from its unique network architecture, introduced carbon material possesses high oxygen content of 13.26%, wide interplanar spacing of 0.

Carbon-enhanced centrifugally-spun SnSb/carbon microfiber composite as advanced anode material for sodium-ion battery.

Antimony tin (SnSb) based materials have become increasingly attractive as a potential anode material for sodium-ion batteries (SIBs) owing to their prominent merit of high capacity. However, cyclic stability and rate capability of SnSb anodes are currently hindered by their large volume change during repeated cycling, which results in severe capacity fading. Herein, we introduce carbon-coated centrifugally-spun SnSb@carbon microfiber (CMF) composites as high-performance anodes for SIBs that can maintain their structural stability during repeated charge-discharge cycles.