Progress on High Voltage PEO-based Polymer Solid Electrolytes in Lithium Batteries

Polymer electrolytes have attracted great interest for next-generation lithium-based batteries on account of safety and high energy density. In this review, we assess recent progress on the design of poly(ethylene oxide)(PEO)-based solid polymer electrolytes in high voltage lithium batteries and identify possible side reactions between PEO-based electrolytes and existing cathodes. We provide an overview of the ways to enhance high voltage resistance of PEO-based electrolytes. Those include components blend, molecular design and interface modification. With these efforts, we want to present new insights into rational design of PEO-based electrolytes to develop solid-state lithium batteries for advanced performance.     

Revealing the Cell Entry Dynamic Mechanism of Single Rabies Virus Particle

The rabies virus is a neurotropic virus that causes fatal diseases in humans and animals. Although studying the interactions between a single rabies virus and the cell membrane is necessary for understanding the pathogenesis, the internalization dynamic mechanism of single rabies virus in living cells remains largely elusive. Here, we utilized a novel force tracing technique based on atomic force microscopy(AFM) to record the process of single viral entry into host cell. We revealed that the force of the rabies virus internalization distributed at (65±25) pN, and the time was identified by two peaks with spacings of (237.2±59.1) and (790.3±134.4) ms with the corresponding speed of 0.12 and 0.04 μm/s, respectively. Our results provide insight into the effects of viral shape during the endocytosis process. This report will be meaningful for understanding the dynamic mechanism of rabies virus early infection.     

Recent Progress in Mass Spectrometry-based Metabolomics for Colorectal Cancer

Metabolomics, one of the latest omics technologies, is employed to reveal overall metabolic trajectories, identify disease causative mechanisms and provide information for preventive diagnosis and drug targeting. Cancer is a disease known to alter cellular metabolism and so metabolomics can play an important role in the early diagnosis of cancer and in the evaluation of medical interventions and treatments for cancer. Many metabolomics studies rely on high-sensitive and high-throughput mass spectrometry platforms. In recent years, various mass spectrometry(MS) methodologies have been developed and enriched the scope of metabolite detection, contributing to disease studies, such as diabetes, cancer, and depression. Colorectal cancer is the third most diagnosed cancer worldwide and its incidence ranked third in China. This review focuses on the mass spectrometry technologies in metabolomics and summarizes the progress of metabolomics research in colorectal cancer.     

Pore Engineering for Covalent Organic Framework Membranes

Membrane technology is of particular significance for the sustainable development of society owing to its potential capacity to tackle the energy shortage and environmental pollution. Membrane materials are the core part of membrane technology. Researchers have always been pursuing predictable structures of advanced membrane materials, which provides a possibility to fully unlock the potential of membranes. Covalent organic frameworks(COFs), with the advantage of controllable pore microenvironment, are considered to be promising candidates to achieve this design concept. The customizable function of COF membranes through pore engineering does well in the enhancement of selective permeability performance, which offers COF membranes with great application potentials in separation and transportation fields. In this context, COF-based membranes have been developed rapidly in recent years. Herein, we present a brief overview on the strategies developed for pore engineering of COF membranes in recent years, including skeleton engineering, pore surface engineering, host-guest chemistry and membrane fabrication. Moreover, the features of transmission or separation of molecules/ions based on COF membranes and corresponding applications are also introduced. In the last part, the challenges and prospects of the development of COF membranes are discussed.     

二维钙钛矿光伏器件

有机-无机杂化卤化物钙钛矿太阳能电池(perovskite solar cells, PSCs)由于其成本低廉、制备工艺简单、光电转换率高等优点引起了越来越多的关注,在下一代半导体光伏技术中显示出巨大的发展潜力。然而PSCs器件在商业化生产应用之前,必须解决某些关键问题,例如器件在湿度、光照和过热条件下缺乏稳定性,性能会急剧衰退。层状二维(two-dimensional, 2D)钙钛矿由于其优异的环境稳定性而受到研究人员的广泛关注。通过引入不同种类的疏水性大体积有机铵阳离子可以在钙钛矿体内形成稳定的2D结构。然而,由于绝缘有机间隔阳离子的存在,使其电荷输运能力受阻并影响光电转换性能。本文根据不同种类2D钙钛矿光伏器件的发展进程,总结了影响2D钙钛矿结构和性能的关键问题,如晶体垂直取向设计、量子阱调控和有机层间隔阳离子替换工程等。最后对2D PSCs的未来发展进行展望。     

Highly Active Electrocatalyst Derived from ZIF-8 Decorated with Iron(III) and Cobalt(III) Porphyrin Toward Efficient Oxygen Reduction in Both Alkaline and Acidic Media

Zeolite imidazole frameworks 8(ZIF-8) and modified ones after pyrolysis are highly promising toward oxygen reduction reaction(ORR). Especially, the compositional modification of ZIF-8 is crucial to the enhancement of ORR performance, yet limited to the substitution of skeletal Zn(II) with other cations or simple physical adsorption of cations. Herein, we report the decoration of ZIF-8 with ORR active hemin(FeP) and Co(III) protoporphyrin(CoP) via the coordination between the peripheral carboxylic group of FeP and CoP with skeletal Zn(II). This allows well control over the quantity of loaded FeP and CoP, critical to the synthesis of advanced electrocatalysts. Subsequent pyrolysis of FeP and CoP co-decorated ZIF-8 leads to highly active ORR electrocatalysts with a half-wave potential(E_1/2) of 0. 913 V(vs. RHE) in 0.1 mol/L KOH aq. and an E_1/2 of 0.803 V(vs. RHE) in 0.1 mol/L HClO₄ aq. Moreover, our electrocatalyst shows much more improved and comparable durability in alkaline and acidic media, respectively, during 3000 cycles of cyclic voltammetry(CV) scanning relative to commercial Pt/C.     

浅析高分子树脂无溶剂生产技术中的高分子凝聚态相关化学问题

在没有溶剂介质参与的高分子聚合反应中,高分子凝聚态的变化与化学反应之间的作用关系变得更加直接。以熔融聚合、反应挤出、固相聚合为代表的高分子树脂无溶剂生产技术是集高分子树脂合成、材料加工制备及工程一体化的新兴科学与技术,是当代材料科学领域发展的前沿领域,代表着高分子树脂生产技术发展的必然趋势。本文将上述这三种典型的树脂工业合成技术及相应机理进行了简要的介绍,并分别以聚对苯二甲酸乙二醇酯(PET)和聚乳酸(PLA)的实际生产研究情况为例,展示三种生产技术之间的相互联系,揭示这三种无溶剂型高分子制备技术过程中出现的高分子凝聚态变化与化学反应之间的基本问题,为广大科研工作提供一些有价值的参考。     

零价铁去除水中(类)金属(含氧)离子技术发展的黄金十年(2011-2021)

应用零价铁(ZVI)去除水中(类)金属(含氧)离子是近年来研究的热点。在ZVI除污染过程中,同步提升ZVI除污的反应活性与电子效率对该技术进一步推广应用至关重要。本文综述了近十年(2011-2021年)ZVI的提升技术,主要涉及硫化、外加弱磁场、投加Fe²⁺、投加氧化剂以及其他新型技术。从不同体系广谱研究以及单一体系具体研究的角度,系统分析了这些技术对ZVI去除含氧水体中(类)金属(含氧)离子的反应活性、去除容量、电子效率的提升表现及作用机制。最后,对ZVI技术未来的研究方向作出了展望,以期促进ZVI技术的进一步完善与发展。本文有望为增强零价铁去除污染物的实际效能提供新的探索方向并完备相关理论基础。     

Rational Design of Ratiometric Fe3+ Fluorescent Probes Based on FRET Mechanism

As the most abundant transition metal element in mammals, iron(Fe) plays a vital role in life activities. It is of great significance to study the variation of Fe³⁺ level in living organisms. In virtue of the advantages of high sensitivity, good selectivity and low damage to living systems, the fluorescence detection of Fe³⁺ has attracted much attention. Compared with the intensity-based fluorescent probe, the ratiometric fluorescent probe has less interference of environmental and can realize quantitative detection. In this study, four ratiometric Fe³⁺ fluorescent probes, R1, R2, R3 and R4_, were designed and synthesized using fluorescence resonance energy transfer(FRET) mechanism to achieve quantitative detection of Fe³⁺. In the FRET systems, 1,8-naphthalimide fluorophore derivatives were adopted as donors while rhodamine B derivatives were selected as receptors. The connection sites of the donor and acceptor in R3 and R4 are different from those in R1 and R2. All the four probes showed good response and selectivity to Fe³⁺. The energy transfer efficiencies of R3 and R4 were obviously higher than those of R1 and R2. This work provided a promising strategy for the development of fluorescent ratiometic Fe³⁺sensors.     

Development of the Self-doping Porous Carbon and Its Application in Supercapacitor Electrode

The massive discharge of biomass wastes not only causes waste of resources, but also pollutes the environment. Therefore, converting biomass wastes into carbon materials is an effective way to solve the above problems. Here, using biomass waste pig nails as raw materials and K₂CO₃ as chemical activators, the N-doped porous carbon(KPNC) is prepared by direct pyrolysis. As an electrode for supercapacitors, the electrochemical tests of KPNCs showed that they exhibited good electrochemical performance and excellent cycling stability. When the current density is 0.2 A/g, the specific capacitance is up to 344.6 F/g. Moreover, it still maintains 97.6% initial capacitance retention after 2000 cycles at a high current density of 5 A/g. Above exceptional electrochemical performances may be ascribed to an appropriate porous structure(S_micro/S_total=80.31%, V_micro/V_total=76.19%), high nitrogen contents(4.44%, atomic fraction), oxygen contents(9.13%, atomic fraction) as well as small internal resistance. The above experimental results show that the conversion of pig nails to porous carbon can reduce the waste of resources and alleviate environmental pollution.