In this Article, bulk-quantity one-dimensional polyaniline (1D PANI) nanowire/tubes with rough surface were prepared by a simple chemical oxidation method. This kind of PANI nanostructure can not only remove Cr(VI) rapidly and effectively in one step from aqueous solution by reducing Cr(VI) to Cr(III) as well as adsorbing the reduced Cr(III) simultaneously, but also be easily regenerated for reuse. During the removal of Cr(VI) process, the as-synthesized PANI was oxidized from emeraldine salt to pernigraniline, and pernigraniline could be reconverted into emeraldine salt by acid treatment. In addition, the morphology of the PANI was not changed after used for Cr(VI) removal. This study not only provides a facile way to fabricate bulk-quantity 1D PANI nanostructure, but also shows a reproducible material for removal of toxic Cr(VI) from wastewater.

A non-precious metal catalyst (NPMC), with nano-porous structure and high BET surface area, is prepared by pyrolyzing the polyaniline on carbon nanospheres using ferric chloride both as an oxidant and iron source. Electrochemical test results show that the catalyst has a high activity and much better stability than that of commercial Pt/C in acid medium.

The van der Waals ferromagnet Fe5GeTe2 has a Curie temperature TC of about 270 K, which is tunable through controlling the Fe deficiency content and can even reach above room temperature. To achieve insights into its ferromagnetic exchange that gives the high TC, the critical behavior has been investigated by measuring the magnetization in Fe5GeTe2 crystal around the ferromagnetic ordering temperature. The analysis of the measured magnetization by using various techniques harmonically reached to a set of reliable critical exponents with TC = 273.7 K, β = 0.3457 ± 0.001, γ = 1.40617 ± 0.003, and δ = 5.021 ± 0.001. By comparing these critical exponents with those predicted by various models, it seems that the magnetic properties of Fe5GeTe2 could be interpreted by a three-dimensional magnetic exchange with the exchange distance decaying as J(r) ≈ r−4.916, close to that of a three-dimensional Heisenberg model with long-range magnetic coupling.

Solid polymer electrolyte (SPE) is one of the choices for many ionic devices, including organic transistors, ion batteries, memristors, and more. However, uncontrollable conductive filament formation seriously affects the performance of the device. In this paper, the PEDOT:PSS was doped to improve the electronic and ionic conductivity of amorphous polymer electrolyte poly­(vinylpyrrolidone) (PVP), realizing the transition of the filaments growth from cathode to anode in atomic switch memristors. Based on the difference in ion and electron mobility and scanning electron microscope observation, the in situ reductions of metal ions inside the dielectric layer can effectively prevent the formation of uncontrollable filaments. The formation of uniformly distributed metal particles in the dielectric layer is similar to co-sputter doping technology, which enables the device to exhibit excellent performance, such as smaller set/reset bias distribution, endurance, and retention. Obviously, this innovative way improves the conductive mechanism of ionic devices.

Cobalt sulfides have been popularly used in energy storage because of their high theoretical capacity and abundant redox reactions. However, poor reaction kinetics, rapid capacity decay, and severe polarization owing to volume changes during electrochemical reaction are still huge challenges for cobalt sulfides in practical applications. Herein, cobalt sulfide yolk–shell spheres were synthesized by phosphorus doping (P‐CoS) to stabilize the structure of cobalt sulfides and improve their electronic/ion conductivity. Kinetic tests and density functional theory calculations confirm that the introduction of phosphorus into cobalt sulfides greatly reduces the diffusion barrier of Li+ in the intrinsic structure, thereby improving the reaction kinetics of electrode materials during the Li+ insertion/extraction process. In consequence, the P‐CoS electrode delivers a high lithium storage capacity (781 mAh g−1 after 100 cycles at 0.2 A g−1), excellent rate capability (489 mAh g−1 at 10 A g−1), and outstanding cycling stability (no significant capacity decay over 4000 cycles at 5 A g−1). Especially for sodium‐ion battery application, the P‐CoS electrode expresses a striking capacity of approximately 260 mAh g−1 at 2 A g−1 after 900 cycles.

Organic luminogens with persistent room‐temperature phosphorescence (RTP) have found a wide range of applications. However, many RTP luminogens are prone to severe quenching in the crystalline state. Herein, we report a strategy to construct a donor‐sp3‐acceptor type luminogen that exhibits aggregation‐induced emission (AIE) while the donor‐sp2‐acceptor counterpart structure exhibits a non‐emissive solid state. Unexpectedly, it was discovered that a trace amount (0.01 %) of the structurally similar derivative, produced by a side reaction with the DMF solvent, could induce strong RTP with an absolute RTP yield up to 25.4 % and a lifetime of 48 ms, although the substance does not show RTP by itself. Single‐crystal XRD‐based calculations suggest that n–σ* orbital interactions as a result of structural similarity may be responsible for the strong RTP in the bicomponent system. This study provides a new insight into the design of multi‐component, solid‐state RTP materials from organic molecular systems.

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