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921.
Dr. Ding Yi Fei Lu Fengchu Zhang Dr. Shoujie Liu Dr. Bo Zhou Denglei Gao Prof. Xi Wang Prof. Jiannian Yao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):15989-15993
Single-atom catalysts have attracted much attention. Reported herein is that regulating charge transfer of lattice oxygen atoms in serial single-atom-doped titania enables tunable hydrogen evolution reaction (HER) activity. First-principles calculations disclose that the activity of lattice oxygen for the HER can be regularly promoted by substituting its nearest metal atom, and doping-induced charge transfer plays an essential role. Besides, the realm of the charge transfer of the active site can be enlarged to the second nearest atom by creating oxygen vacancies, resulting in further optimization for the HER. Various single-atom-doped titania nanosheets were fabricated to validate the proposed model. Taking advantage of the localized charge transfer to the lattice atom is demonstrated to be feasible for realizing precise regulation of the electronic structures and thus catalytic activity of the nanosheets. 相似文献
922.
Xiao-Qin Liu Ke Zhang Prof. Jian-Feng Gao Prof. Yu-Zhe Chen Prof. Chen-Ho Tung Prof. Li-Zhu Wu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(52):23662-23666
Hypoxia is a parameter related to many diseases. Ratiometric hypoxia probes often rely on a combination of an O2-insensitive fluorophore and an O2-sensitive phosphor in a polymer matrix, which require high cost and multi-step synthesis of transition metal complexes. The two-chromophore hypoxia probes encounter unfavorable energy transfer processes and different stabilities of the chromophores. Reported herein is a pure organic ratiometric hypoxia nanoprobe, assembled by a monochromophore, naphthalimide ureidopyrimidinone (BrNpA-UPy), bridged by a bis-UPy-functionalized benzyl skeleton. The joint factors of quadruple hydrogen bonding, the rigid backbone of UPy, and bromine substitution of the naphthalimide derivative facilitate bright phosphorescence (ΦP=7.7 %, τP=3.2 ms) and fluorescence of the resultant nanoparticles (SNPs) at room temperature, which enable accurate, ratiometric, sensitive oxygen detection (Ksv=189.6 kPa−1) in aqueous solution as well as in living HeLa cells. 相似文献
923.
Dr. Wei Bai Jingyu Gao Dr. Kun Li Gongrui Wang Dr. Tengfei Zhou Pengju Li Prof. Shengyong Qin Prof. Genqiang Zhang Prof. Zaiping Guo Prof. Chong Xiao Prof. Yi Xie 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(40):17647-17651
Volume expansion and poor conductivity are two major obstacles that hinder the pursuit of the lithium-ion batteries with long cycling life and high power density. Herein, we highlight a misfit compound PbNbS3 with a soft/rigid superlattice structure, confirmed by scanning tunneling microscopy and electrochemical characterization, as a promising anode material for high performance lithium-ion batteries with optimized capacity, stability, and conductivity. The soft PbS sublayers primarily react with lithium, endowing capacity and preventing decomposition of the superlattice structure, while the rigid NbS2 sublayers support the skeleton and enhance the migration of electrons and lithium ions, as a result leading to a specific capacity of 710 mAh g−1 at 100 mA g−1, which is 1.6 times of NbS2 and 3.9 times of PbS. Our finding reveals the competitive strategy of soft/rigid structure in lithium-ion batteries and broadens the horizons of single-phase anode material design. 相似文献
924.
Prof. Dr. Su-Yun Zhang Dr. Han Miao Dr. He-min Zhang Jun-Hao Zhou Prof. Dr. Qiang Zhuang Prof. Dr. Yu-Jia Zeng Prof. Dr. Zhiming Gao Prof. Dr. Jiayin Yuan Prof. Dr. Jian-Ke Sun 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22293-22300
The capability to significantly shorten the synthetic period of a broad spectrum of open organic materials presents an enticing prospect for materials processing and applications. Herein we discovered 1,2,4-triazolium poly(ionic liquid)s (PILs) could serve as a universal additive to accelerate by at least one order of magnitude the growth rate of representative imine-linked crystalline open organics, including organic cages, covalent organic frameworks (COFs), and macrocycles. This phenomenon results from the active C5-protons in poly(1,2,4-triazolium)s that catalyze the formation of imine bonds, and the simultaneous salting-out effect (induced precipitation by decreasing solubility) that PILs exert on these crystallizing species. 相似文献
925.
Yanan Jiang Wenjie Ma Yujuan Qiao Yifei Xue Jiahao Lu Jun Gao Nannan Liu Fei Wu Prof. Ping Yu Prof. Lei Jiang Prof. Lanqun Mao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12895-12899
Biological ion channels and ion pumps with sub-nanometer sizes modulate ion transport in response to external stimuli. Realizing such functions with sub-nanometer solid-state nanopores has been an important topic with wide practical applications. Herein, we demonstrate a biomimetic photoresponsive ion channel and photodriven ion pump using a porphyrin-based metal–organic framework membrane with pore sizes comparable to hydrated ions. We show that the molecular-size pores enable precise and robust optoelectronic ion transport modulation in a broad range of concentrations, unparalleled with conventional solid-state nanopores. Upon decoration with platinum nanoparticles to form a Schottky barrier photodiode, photovoltage across the membrane is generated with “uphill” ion transport from low concentration to high concentration. These results may spark applications in energy conversion, ion sieving, and artificial photosynthesis. 相似文献
926.
Xuan Wei Diao Zheng Ming Zhao Dr. Hongzhong Chen Xun Fan Bin Gao Dr. Long Gu Dr. Yi Guo Dr. Jianbin Qin Prof. Jing Wei Prof. Yanli Zhao Prof. Guangcheng Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(34):14747-14754
Heteroatom-doped polymers or carbon nanospheres have attracted broad research interest. However, rational synthesis of these nanospheres with controllable properties is still a great challenge. Herein, we develop a template-free approach to construct cross-linked polyphosphazene nanospheres with tunable hollow structures. As comonomers, hexachlorocyclotriphosphazene provides N and P atoms, tannic acid can coordinate with metal ions, and the replaceable third comonomer can endow the materials with various properties. After carbonization, N/P-doped mesoporous carbon nanospheres were obtained with small particle size (≈50 nm) and high surface area (411.60 m2 g−1). Structural characterization confirmed uniform dispersion of the single atom transition metal sites (i.e., Co-N2P2) with N and P dual coordination. Electrochemical measurements and theoretical simulations revealed the oxygen reduction reaction performance. This work provides a solution for fabricating diverse heteroatom-containing polymer nanospheres and their derived single metal atom doped carbon catalysts. 相似文献
927.
Dr. Zhenhua Gao Baoyuan Xu Tongjin Zhang Zhen Liu Weiguang Zhang Xun Sun Yang Liu Dr. Xue Wang Dr. Zifei Wang Prof. Yongli Yan Prof. Fengqin Hu Prof. Xiangeng Meng Prof. Yong Sheng Zhao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(43):19222-19226
Micro/nanoscale photonic barcodes based on multicolor luminescent segmented heterojunctions hold potential for applications in information security. However, such multicolor heterojunctions reported thus far are exclusively based on static luminescent signals, thus restricting their application in advanced confidential information protection. Reported here is a strategy to design responsive photonic barcodes with heterobimetallic (Tb3+/Eu3+) metal—organic framework multicolor heterostructures. The spatial colors could be precisely controlled by thermally manipulating the energy-transfer process between the two lanthanides, thus achieving responsive covert photonic barcodes. Also demonstrated is that spatially resolved responsive barcodes with multi-responsive features could be created in a single heterostructure. These findings offer unique opportunities to purposely design highly integrated responsive microstructures and smart devices toward advanced anti-counterfeiting applications. 相似文献
928.
Xiao-Xu Ba Tian Gao Mian Yang Peng Jiang Feng-Lei Jiang Yi Liu 《Journal of solution chemistry》2020,49(1):100-116
As one of the newly emerged nanomaterials, graphene quantum dots (GQDs) have shown great application potential as tracking probes and drug carriers in biological areas. The GQDs synthesized via the nitric acid reflux method in this study turned out to quench the fluorescence of human serum albumin (HSA) and gamma globulin (γ-globulin) in two different functional ways. The fluorescence quenching effect of GQDs on HSA is a static pattern and the predominant interaction forces are hydrogen bonds and van der Waals forces. Distinct from HSA, the interaction between GQDs and γ-globulins belongs to dynamic quenching and is driven by electrostatic forces. Ultraviolet–visible (UV–vis) differential spectrometry and transient state fluorescence spectrometry were also utilized to further confirm their quenching types. Also, thermodynamics parameters, the enthalpy change (ΔH) and entropy change (ΔS) of reaction between GQDs and proteins were obtained through a series of calculations from the van’t Hoff equation. Furthermore, the effect of GQDs on the conformational structure of proteins was characterized by synchronous fluorescence spectra (SFS), three-dimensional (3D) fluorescence and circular dichroism (CD) spectra. In addition, the binding mechanism of GQDs with HSA and γ-globulins were proposed based on the obtained experimental results. The research on the reaction between GQDs with HSA and γ-globulins offers promising insight for the further application of nanomaterials in biomedical fields. 相似文献
929.
Zidong Liu Zhe Gao Jiaqi Wang Jie Shi Jinding Liu Deqing Chen Wenyan Li Jiangling Guo Xiaojuan Cheng Ting Hao Zeqin Li Yanhua Li Jiangwei Yan Gengqian Zhang 《Electrophoresis》2020,41(15):1364-1373
In the past decades, messenger RNA (mRNA) biomarkers have been employed to identify the origin of body fluids in forensic medicine. We hypothesized that the polymorphism of mRNA could be applied to identify individuals in mixture samples composed of two body fluids. In this study, we selected five blood-specific mRNA biomarkers of venous blood (SPTB, CD3G, AMICA1, ANK1, and GYPA) that encompass 16 SNPs to identify the mixture contributor(s). Five specific gene markers for menstrual blood, semen, skin, saliva, and vaginal secretions were amplified and typed as body-fluid positive controls. We established the system of multiplex PCR and single base extension (SBE) reaction followed by CE. The amplicon size was between 90bp and 294bp. The peripheral blood specificity was examined against other human body fluids, including saliva, semen, skin, menstrual blood, and vaginal secretion. The 16 SNPs were peripheral blood specific and could be successfully typed in homemade mixtures which are composed of different body fluids with 1 ng peripheral blood mRNA added. This system showed a supersensitivity (1:100) in detecting the trace amount of peripheral blood mixed in other body fluids and a combined discrimination power (CDP) of 0.99929 in Chinese population. It was the first time to establish a method for identifying the blood donors and deconvoluting mixtures through detecting mRNA polymorphism with SNaPshot assay. This peripheral blood specific SNP typing system showed high sensitivity to the typing of blood source specific markers regardless of other body fluids in the mixture. 相似文献
930.
Jiajing Wu Dr. Jianyu Tong Dr. Yuan Gao Dr. Aifei Wang Prof. Tao Zhang Prof. Hairen Tan Prof. Shuming Nie Prof. Zhengtao Deng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(20):7812-7816
A novel triphenylphosphine (TPP) treatment strategy was developed to prepare the near-infrared emission CsPbI3 nanocrystal (NC)-polymer composite thin-film luminescent solar concentrators (LSCs) featuring high absolute photoluminescence quantum yield (PLQY), low reabsorption, and high stability. The PL emission of the LSCs is centered at about 700 nm with 99.4±0.4 % PLQY and narrow full width at half maximum (FWHM) of 75 meV (30 nm). Compared with LSCs prepared with classic CsPbI3 NCs, the stability of the LSCs after TPP treatments has been greatly improved, even after long-term (30 days) immersion in water and strong mercury-lamp irradiation (50 mW cm−2). Owing to the presence of lone-pair electrons on the phosphorus atom, TPP is also used as a photoinitiator, with higher efficiency than other common photoinitiators. Large-area (ca. 75 cm2) infrared LSCs were achieved with a high optical conversion efficiency of 3.1 % at a geometric factor of 10. 相似文献