A Long‐Cycling Aqueous Zinc‐Ion Pouch Cell: NASICON‐Type Material and Surface Modification

Aqueous zinc‐ion batteries (ZIBs) have become the highest potential energy storage system for large‐scale applications owing to the high specific capacity, good safety and low cost. In this work, a NASICON‐type Na₃V₂(PO₄)₃ cathode modified by a uniform carbon layer (NVP/C) has been synthesized via a facile solid‐state method and exhibited significantly improved electrochemical performance when working in an aqueous ZIB. Specifically, the NVP/C cathode shows an excellent rate capacity (e. g., 48 mAh g^?1 at 1.0 A g^?1). Good cycle stability is also achieved (e. g., showing a capacity retention of 88% after 2000 cycles at 1.0 A g^?1). Furthermore, the Zn²⁺ (de)intercalation mechanism in the NVP cathode has been determined by various ex‐situ techniques. In addition, a Zn||NVP/C pouch cell has been assembled, delivering a high capacity of 89 mAhg^?1 at 0.2 A g^?1 and exhibiting a superior long cycling stability.     

Zero‐Dimensional Hybrid Cd‐Based Perovskites with Broadband Bluish White‐Light Emissions

Recently, low‐dimensional organic‐inorganic hybrid metal halide perovskites acting as single‐component white‐light emitting materials have attracted extensive attention, but most studies concentrate on hybrid lead perovskites. Herein, we present two isomorphic zero‐dimensional (0D) hybrid cadmium perovskites, (HMEDA)CdX₄ (HMEDA=hexamethylenediamine, X=Cl ( 1 ), Br ( 2 )), which contain isolated [CdX₄]^2? anions separated by [HMEDA]²⁺ cations. Under UV light excitation, both compounds display broadband bluish white‐light emission (515 nm for 1 and 445 nm for 2 ) covering the entire visible light spectrum with sufficient photophysical stabilities. Remarkably, compound 2 shows a high color rendering index (CRI) of 83 enabling it as a promising candidate for single‐component WLED applications. Based on the temperature‐dependent, powder‐dependent and time‐resolved PL measurements as well as other detailed studies, the broadband light emissions are attributed to self‐trapped excitons stemming from the strong electron‐phonon coupling.     

Regulation of Cathode‐Electrolyte Interphase via Electrolyte Additives in Lithium Ion Batteries

As the power supply of the prosperous new energy products, advanced lithium ion batteries (LIBs) are widely applied to portable energy equipment and large‐scale energy storage systems. To broaden the applicable range, considerable endeavours have been devoted towards improving the energy and power density of LIBs. However, the side reaction caused by the close contact between the electrode (particularly the cathode) and the electrolyte leads to capacity decay and structural degradation, which is a tricky problem to be solved. In order to overcome this obstacle, the researchers focused their attention on electrolyte additives. By adding additives to the electrolyte, the construction of a stable cathode‐electrolyte interphase (CEI) between the cathode and the electrolyte has been proven to competently elevate the overall electrochemical performance of LIBs. However, how to choose electrolyte additives that match different cathode systems ideally to achieve stable CEI layer construction and high‐performance LIBs is still in the stage of repeated experiments and exploration. This article specifically introduces the working mechanism of diverse electrolyte additives for forming a stable CEI layer and summarizes the latest research progress in the application of electrolyte additives for LIBs with diverse cathode materials. Finally, we tentatively set forth recommendations on the screening and customization of ideal additives required for the construction of robust CEI layer in LIBs. We believe this minireview will have a certain reference value for the design and construction of stable CEI layer to realize desirable performance of LIBs.     

Synthesis,crystal structures and magnetic and electrochemiluminescence properties of three manganese(II) complexes

Three novel complexes, namely, penta‐μ‐acetato‐bis(μ₂‐2‐{[2‐(6‐chloropyridin‐2‐yl)hydrazinylidene]methyl}‐6‐methoxyphenolato)‐μ‐formato‐tetramanganese(II), [Mn₄(C₁₃H₁₁ClN₃O₂)₂(C₂H₃O₂)_5.168(CHO₂)_0.832], 1 , hexa‐μ₂‐acetato‐bis(μ₂‐2‐{[2‐(6‐bromopyridin‐2‐yl)hydrazinylidene]methyl}‐6‐methoxyphenolato)tetramanganese(II), [Mn₄(C₁₃H₁₁BrN₃O₂)₂(C₂H₃O₂)₆], 2 , and catena‐poly[[μ₂‐acetato‐acetatoaqua(μ₂‐2‐{[2‐(6‐chloropyridin‐2‐yl)hydrazinylidene]methyl}‐6‐methoxyphenolato)dimanganese(II)]‐μ₂‐acetato], [Mn₂(C₁₃H₁₁ClN₃O₂)(C₂H₃O₂)₃(H₂O)]_n, 3 , have been synthesized using solvothermal methods. Complexes 1 – 3 were characterized by IR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. Complexes 1 and 2 are tetranuclear manganese clusters, while complex 3 has a one‐dimensional network based on tetranuclear Mn₄(L¹)₂(CH₃COO)₆(H₂O)₂ building units (L¹ is 2‐{[2‐(6‐chloropyridin‐2‐yl)hydrazinylidene]methyl}‐6‐methoxyphenolate). Magnetic studies reveal that complexes 1 – 3 display dominant antiferromagnetic interactions between Mn^II ions through μ₂‐O bridges. In addition, 1 – 3 also display favourable electrochemiluminescence (ECL) properties.     

稀土长链配合物的合成及其性质研究

通过筛选配体、优化合成条件,设计合成了以Tb3 为中心离子,以苯甲酸、水杨酸、对羟基苯甲酸、对甲基苯甲酸、大茴香酸、间氯苯甲酸、对氨基苯甲酸、磺基水杨酸为第一配体,以十一烯酸为第二配体合成8种铽三元荧光配合物。通过红外光谱分析、紫外光谱分析、元素分析、EDTA配位滴定分析以及电导率的测定确定了铽三元荧光配合物的分子结构和组成,采用热分析仪研究了铽三元荧光配合物的热稳定性能,其热稳定性强弱顺序为:Tb(SSA)(UA).3H2O磺基水杨酸>大茴香酸>对氨基苯甲酸>苯甲酸>水杨酸>对羟基苯甲酸>间氯苯甲酸,同时对产生上述现象的原因进行了初步的理论探讨。     

Lu-Eu共掺杂Ga2O3的光电性质的第一性原理计算

宽禁带半导体β-Ga₂O₃因为具有优良的物理化学性能而成为研究热点.本文基于DFT(Density Functional Theory)的第一性原理方法,先采用PBE(Perdew-Burke-Ernzerhof)中的GGA(Generalized Gradient Approximation)和GGA+U(Generalized Gradient Approximation-Hubbard U)的方法计算了本征β-Ga₂O₃,Lu掺杂浓度为12.5%的β-Ga₂O₃及Lu-Eu共掺杂浓度为25%的β-Ga₂O₃结构的晶格常数、能带结构和体系总能量.发现采用GGA+U的方法计算的带隙值更接近实验值,于是采用GGA+U的方法计算了本征β-Ga₂O₃,Lu掺杂的β-Ga₂O₃以及Lu-Eu共掺杂的β-Ga₂O...     

Enhanced Reproducibility of Positive Temperature Coefficient Effect of CB/HDPE/PVDF Composites with the Addition of Ionic Liquid

Developing an effective method for improving the reproducibility of positive temperature coefficient(PTC) effect is of great significance for large-scale application of polymer based PTC composites, owing to its contribution to the security and reliability. Herein, we developed a carbon black(CB)/high density polyethylene(HDPE)/poly(vinylidene fluoride)(PVDF) composite with outstanding PTC reproducibility, by incorporating 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([OMIm][NTf_2]) into the composite. After multiple repeated temperature cycles, the PTC performance of as-prepared material keeps almost unchanged and the varition of resistance at room temperature is less than 7%. Our studies revealed that [OMIm][NTf2] contributes to the improvement of PTC reproducibility in two ways:(i)it acts as an efficient plasticizer for refining the co-continuous phase morphology of HDPE/PVDE blends;(ii) it inhibits the crystallization of PVDF through the dilution effect, leading to more overlaps of the volume shrinkage process of HDPE and PVDF melt which results in the decrease of interface gap between HDPE and PVDF. This study demonstrated that ionic liquids as the multifunctional agents have great potential for improving the reproducibility in the application of the binary polymer based PTC composites.     

Natural Polyphenols for the Preservation of Meat and Dairy Products

Food spoilage makes foods undesirable and unacceptable for human use. The preservation of food is essential for human survival, and different techniques were initially used to limit the growth of spoiling microbes, e.g., drying, heating, salting, or fermentation. Water activity, temperature, redox potential, preservatives, and competitive microorganisms are the most important approaches used in the preservation of food products. Preservative agents are generally classified into antimicrobial, antioxidant, and anti-browning agents. On the other hand, artificial preservatives (sorbate, sulfite, or nitrite) may cause serious health hazards such as hypersensitivity, asthma, neurological damage, hyperactivity, and cancer. Thus, consumers prefer natural food preservatives to synthetic ones, as they are considered safer. Polyphenols have potential uses as biopreservatives in the food industry, because their antimicrobial and antioxidant activities can increase the storage life of food products. The antioxidant capacity of polyphenols is mainly due to the inhibition of free radical formation. Moreover, the antimicrobial activity of plants and herbs is mainly attributed to the presence of phenolic compounds. Thus, incorporation of botanical extracts rich in polyphenols in perishable foods can be considered since no pure polyphenolic compounds are authorized as food preservatives. However, individual polyphenols can be screened in this regard. In conclusion, this review highlights the use of phenolic compounds or botanical extracts rich in polyphenols as preservative agents with special reference to meat and dairy products.