There is a great challenge to employ an electrocatalyst that has high efficiency, is earth-abundant, and is a non-noble metal for oxygen evolution reaction (OER). Herein, we reported a low-cost and highly efficient OER catalyst, Fe-doped NiCoP nanosheet arrays in situ grown on nickel foam (NiCoFeP/NF), which was synthesized via a simple and mild hydrothermal and phosphorization method. In 1 M KOH solution, the as-prepared NiCoFeP/NF produces a larger current density of 200 mA·cm–2 at a low overpotential of 271 mV and exhibits a low Tafel slope of 45 mV·dec–1, which is superior to commercial RuO2. The outstanding OER performance of the as-prepared NiCoFeP/NF can be attributed to the synergetic effects among Fe, Ni, and Co elements, unique nanosheet arrays structure, and the great intrinsic electrocatalytic activity. On the basis of the above factors, the as-prepared NiCoFeP/NF may work as a promising OER electrocatalyst.

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The microscopic mechanism of potassium permanganate (KMnO 4 ) modification and the properties of ramie fiber/polypropylene (RF/PP) composites were investigated with experiments and molecular dynamics (MD) simulations at the molecular and atomic levels. The MD simulations suggested that the microscopic modification mechanism for the improved properties of the KMnO 4 modified RF/PP composites were contributed to the decrease of the free volume of cellulose molecular and increase of the weak Van der Waals force at the interface of the modified fiber and PP matrix. The decrease of the free volume of cellulose molecular can reduce the water absorption of natural fiber. Conversely, the increase in the weak Van der Waals force at interface can improve the interface adhesion strength of the composites and further result in the improvement of the compatibility of RF/PP composites. Additionally, the experimental work showed that KMnO 4 treatment led to a higher surface roughness of the modified fiber besides the oxidization effect of oxidizing hydroxyl groups within cellulose molecular to be aldehyde and carboxyl groups. This can achieve a better bond strength at interface of fiber and polymer matrix, and finally resulted in the good mechanical properties of the KMnO 4 modified RF/PP composites. POLYM. COMPOS., 00:000-000,

In this article, hydroxyl-terminated polybutadiene (HTPB) was chemically transformed into multiamine, hydroxy polybutadiene (AEHTPB) by the adoption of appropriate synthesis strategies. The structure of AEHTPB was confirmed by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR). The modification degree was altered by adjusting reaction conditions to find out the effect of structural change on various physical properties, including the viscosity and glass transition temperature (T g ) of AEHTPB. Adding AEHTPB to the HTPB binder system could improve the cross-link density and strength of the polyurethane elastomer. Meanwhile, the experiment results indicated that AEHTPB could inhibit the low-temperature decomposition of ammonium perchlorate (AP) by forming a dense coating on the surface of AP. Then, the propellant level studies were conducted with the use of AEHTPB/HTPB mixture as a binder. As a result, the burning rate of propellant containing AEHTPB (5 wt %) was found to be reduced by 10.8% compared to HTPB-based propellant, and the mechanical properties of the propellant were superior to those of HTPB-based propellant with an improvement of 46.2% in tensile strength and 35.1% enhancement in elongation at break. Finally, tensile testing and observation of fracture surface morphology further demonstrated that AEHTPB had a significant bonding effect on AP-based propellant.

Lithium‐ion capacitors (LICs), composed of a lithium ion battery (LIB)‐type electrode and an electrochemical capacitor (EC)‐type electrode (non‐Faradic), operating in a lithium ion‐containing electrolyte, have the potential to deliver high energy density, high power density and long cycle life simultaneously. In this minireview, we focus on the development of practical LICs, which has been barely introduced in previous reviews, to supplement their development course. This minireview includes the introduction of fundamentals, analysis of the key parameters, and review of the key technologies of practical LIC systems. The practical LIC technologies have been summarized and discussed in contrast to the commercial ECs. Finally, we propose the future research for LICs in terms of materials and their properties, which aims to provide guidelines for the researchers in the fields of LICs.

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