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With the incorporation of tailorable organic electronic materials as channel and storage materials, organic field‐effect transistor (OFET)‐based memory has become one of the most promising data storage technologies for hosting a variety of emerging memory applications, such as sensory memory, storage memory, and neuromorphic computing. Here, the recent state‐of‐the‐art progresses in the use of small molecules for OFET nonvolatile memory and artificial synapses are comprehensively reviewed, focusing on the characteristic features of small molecules in versatile functional roles (channel, storage, modifier, and dopant). Techniques for optimizing the storage capacity, speed, and reliability of nonvolatile memory devices are addressed in detail. Insight into the use of small molecules in artificial synapses constructed on OFET memory is also obtained in this emerging field. Finally, the strategies of molecular design for improving memory performance in view of small molecules as storage mediums are discussed systematically, and challenges are addressed to shed light on the future development of this vital research field.

Owing to their unique optical, electronic, and catalytic properties, metal nitrides nanostructures are widely used in optoelectronics, clean energy, and catalysis fields. Despite great progress has been achieved, synthesis of defect-rich (DR) bimetallic nitride nanocrystals or related nanohybrids remains a challenge, and their electrocatalytic application for oxygen evolution reaction (OER) has not been fully studied. Herein, the DR-Ni 3 FeN nanocrystals and N-doped graphene (N-G) nanohybrids (DR-Ni 3 FeN/N-G) are fabricated through temperature-programmed annealing and nitridation treatment of NiFe-layered double hydroxides/graphene oxide precursors by controlling annealing atmosphere. In the nanohybrids, the DR-Ni 3 FeN nanocrystals are anchored on N-G, and mainly show twin crystal defects besides ≈10% of stacking faults. Such nanohybrids can efficiently catalyze OER in alkaline media with a small overpotential (0.25 V) to attain the current density of 10 mA cm −2 and a high turnover frequency (0.46 s −1 ), superior to their counterparts (the nearly defect-free Ni 3 FeN/N-G), commercial IrO 2 , and the-state-of-art reported OER catalysts. Except for the superior activity, they show better durability than their counterparts yet. As revealed by microstructural, spectroscopic, and electrochemical analyses, the enhanced OER performance of DR-Ni 3 FeN/N-G nanohybrids originates from the abundant twin crystal defects in Ni 3 FeN active phase and the strong interplay between

Phase-inversion combined tape casting technology was applied to fabricate P-SOFCs, which demonstrated great performance for CH3OH containing fuel.

During the past decades, π-conjugated polymers have been studied intensively owing to their potential applications in organic optoelectronic devices, such as polymeric light-emitting diodes, bulk heterojunction solar cells, organic field-effect transistors (OFETs), organic memories, biosensors, and actuators. 1,2 The performance of organic devices is determined not only by the inherent electronic structures of individual polymer chain 3,4 but also by multiscale morphologies that were constructed by the drive of supramolecular interactions or van der Waals' forces. Many efforts have been made to design the controllable welldefined nanostructures or hierarchically ordered assemblies in the field of supramolecular semiconductors and electronics for the high-performance or new functional devices. 5,6 One typical example is that ordered self-organization of polythiophenes dramatically influences the performance of bulk heterojunction photovoltaic cells as well as the mobility of OFETs. 7,8 Lightemitting polyfluorenes (PFs) is another impressive example of polymorphisms, including amorphous phase, semicrystalline (R-) phase and R 0 -phase, β-phase, and nematic liquid crystalline (N-) phase. These abundant phases provide a unique opportunity to study the relationship between phase morphology and device performances. 9-13 For example, PFO thin film containing the β-phase exhibits the excellent spectral stability in PLEDs and the pumped lasers with low threshold. 14-16 In this context, it is of the utmost importance to explore further the unique morphology and phase of π-conjugated polymers, which are based on its unique self-assembly mode and supramolecular interactions. Supramolecular gel is a fascinating state that appears solid-like and yet is composed predominantly of a liquid and a small amount of gelators stabilized by supramolecular interactions with 3D networks. 17-20 Until now, low-molecular-mass organogels (LMOGs) have been applied in a wide range of fields, such as biomimetics, separations, drug delivery, soft templates, and tissue engineering. 21-24 Steroid or lipid units have served as gelators to generate cross-linking points in the 3D networks. 25 In addition, some electronically inactive comb-shaped polymers (isotactic and syndiotactic polystyrene (PS), 26 poly(methyl methacrylate), 27 and polyesters 28 ) have also been found to form gel networks easily owing to their unique helical conformations. However, little attention has been paid to π-conjugated polymers. 29-32 Supramolecular π-conjugated polymer gels (SCPGs) can be served as one kind of semiconducting soft materials with distinguished porous structures that may find applications in nanosensors, 33 mimic-artificial muscle, 34 super capacitor, 35 and lithium battery material. 36 Poly(3-alkylthiophene)-based gels were prepared by quenching xylene solution at 150°C, and its conductivity was improved. 37,38 ABSTRACT: Supramolecular π-conjugated polymer-based gels (SCPGs) are one important kind of semiconducting soft materials. Herein we demonstrate a p...

Cubic perovskite SrCoO3−δ was successfully prepared through simple anion F-doping and demonstrated great OER performance.

As one class of important functional materials, transition metal phosphides (TMPs) nanostructures show promising applications in catalysis and energy storage fields. Although great progress has been achieved, phase‐controlled synthesis of cobalt phosphides nanocrystals or related nanohybrids remains a challenge, and their use in overall water splitting (OWS) is not systematically studied. Herein, three kinds of cobalt phosphides nanocrystals encapsulated by P‐doped carbon (PC) and married with P‐doped graphene (PG) nanohybrids, including CoP@PC/PG, CoP‐Co2P@PC/PG, and Co2P@PC/PG, are obtained through controllable thermal conversion of presynthesized supramolecular gels that contain cobalt salt, phytic acid, and graphene oxides at proper temperature under Ar/H2 atmosphere. Among them, the mixed‐phase CoP‐Co2P@PC/PG nanohybrids manifest high electrocatalytic activity toward both hydrogen and oxygen evolution in alkaline media. Remarkably, using them as bifunctional catalysts, the fabricated CoP‐Co2P@PC/PG||CoP‐Co2P@PC/PG electrolyzer only needs a cell voltage of 1.567 V for driving OWS to reach the current density at 10 mA cm−2, superior to their pure‐phase counterparts and recently reported bifunctional catalysts based devices. Also, such a CoP‐Co2P@PC/PG||CoP‐Co2P@PC/PG device exhibits outstanding stability for OWS. This work may shed some light on optimizing TMPs nanostructures based on phase engineering, and promote their applications in OWS or other renewable energy options.

Driven by the demand to minimize fluctuation in common renewable energies, reversible solid oxide cells (RSOCs) have drawn increasing attention for they can operate either as fuel cells to produce electricity or as electrolysis cells to store electricity. Unfortunately, development of proton-conducting RSOCs (P-RSOCs) faces a major challenge of poor reliability because of the high content of steam involved in air electrode reactions, which could seriously decay the lifetime of air electrode materials. In this work, a very stable and efficient air electrode, SrEuFeCoO (SEFC) with layer structure, is designed and deployed in P-RSOCs. X-ray diffraction analysis and High-angle annular dark-filed scanning transmission electron microscopy images of SEFC reveal that Sr atoms occupy the center of perovskite slabs, whereas Eu atoms arrange orderly in the rock-salt layer. Such a special structure of SEFC largely depresses its Lewis basicity and therefore its reactivity with steam. Applying the SEFC air electrode, our button switches smoothly between both fuel cell and electrolysis cell (EC) modes with no obvious degradation over a 135 h long-term test under wet H (∼3% HO) and 10% HO-air atmospheres. A record of over 230 h is achieved in the long-term stability test in the EC mode, doubling the longest test that had been previously reported. Besides good stability, SEFC demonstrates great catalytic activity toward air electrode reactions when compared with traditional LaSrCoFeO air electrodes. This research highlights the potential of stable and efficient P-RSOCs as an important part in a sustainable new energy power system.