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901.
Jingjing Liu Min Wu Yutong Pan Yukun Duan Ziliang Dong Yu Chao Zhuang Liu Bin Liu 《Advanced functional materials》2020,30(13)
Nowadays various inorganic nanoparticles that generate highly reactive hydroxyl radical ( · OH) on the basis of Fenton‐like catalytic activity of metal ions have been designed for chemodynamic therapy. However, the high level of adaptive antioxidants [glutathione (GSH)] in cancer cells could effectively consume · OH to compromise the treatment efficiency and biosafety of these inorganic nanoparticles, and this is a general concern in chemodynamic therapy. Herein, a new biodegradable nanoscale coordination polymer (NCP) is developed by integration of cisplatin prodrug (DSCP) and iron (III) ions through a reverse microemulsion method. The DSCP in the NCPs could react with GSH to release free cisplatin, while the iron (III) ions could be reduced by GSH into iron (II) to enable Fenton reaction, subsequently leading to amplified intracellular oxidative stress. After surface modification of polyethylene glycol (PEG) and cyclo[Arg‐Gly‐Asp‐D‐Phe‐Lys(mpa)] peptide (cRGD), Fe‐DSCP‐PEG‐cRGD shows an excellent targeting effect against αvβ3‐integrin overexpressed tumor cells. Furthermore, Fe‐DSCP‐PEG‐cRGD enables significant chemo and chemodynamic therapy with dramatically enhanced therapeutic efficiency in comparison to relative monotherapies. Importantly, Fe‐DSCP‐PEG‐cRGD could be efficiently cleared out from mice through feces and urine postinjection 7 days. The NCP presented in this work is simple and economical, which shows great biodegradability and biosafety for potential clinical translation. 相似文献
902.
Yuchen Qin Wenlong Zhang Kai Guo Xiaobiao Liu Jiaqi Liu Xiaoyu Liang Xiaopeng Wang Daowei Gao LiYong Gan Yating Zhu Zhicheng Zhang Wenping Hu 《Advanced functional materials》2020,30(11)
Tuning the intrinsic strain of Pt‐based nanomaterials has shown great promise for improving the oxygen reduction reaction (ORR) performance. Herein, reported is a tunable surface strain in penta‐twinned ternary Pt–Cu–Mn nanoframes (NFs). Pt–Cu–Mn ultrafine NFs (UNFs) exhibit ≈1.5% compressive strain compared to Pt–Cu–Mn pentagonal NFs (PNFs) and show the superior activity toward ORR in an alkaline environment. Specifically, the specific and mass activity of Pt–Cu–Mn UNFs are 3.38 mA cm?2 and 1.45 A mg?1, respectively, which is 1.45 and 1.71 times higher than that of Pt–Cu–Mn PNFs, demonstrating that compressive strain in NFs structure can effectively enhance the catalytic activity of ORR. Impressively, Pt–Cu–Mn UNFs exhibit 8.67 and 9.67 times enhanced specific and mass activity compared with commercial Pt/C. Theoretical calculations reveal that compression on the surface of Pt–Cu–Mn UNFs can weaken the bonding strengths and adsorption of oxygen‐containing intermediates, resulting in an optimal condition for ORR. 相似文献
903.
Xin Guan Hao‐Hao Yin Xiao‐Hong Xu Guang Xu Yan Zhang Bang‐Guo Zhou Wen‐Wen Yue Chang Liu Li‐Ping Sun Hui‐Xiong Xu Kun Zhang 《Advanced functional materials》2020,30(27)
Reactive oxygen species (ROS) depletion and low ROS production that result from the intratumoral redox metabolism equilibrium and low energy conversion efficiency from ultrasound mechanical energy to ROS‐represented chemical energy, respectively, are two vital inhibitory factors of sonodynamic therapy (SDT). To address the two concerns, a tumor metabolism‐engineered composite nanoplatform capable of intervening intratumoral ROS metabolism, breaking the redox equilibrium, and reshaping the tumor microenvironment is constructed to reinforce SDT against tumors. In this metabolism‐engineered nanoplatform, Nb2C nanosheets serve as the scaffold to accommodate TiO2 sonosensitizers and l ‐buthionine‐sulfoximine. Systematic experiments show that such nanoplatforms can reduce ROS depletion via suppressing glutathione synthesis and simultaneously improving ROS production via the Nb2C‐enhanced production and separation of electron–hole pairs. Contributed by the combined effect, net ROS content can be significantly elevated, which results in the highly efficient anti‐tumor outcomes in vivo and in vitro. Moreover, the combined design principles, that is, tumor metabolism modulation for reducing ROS depletion and electron–hole pair separation for facilitating ROS production, can be extended to other ROS‐dependent therapeutic systems. 相似文献
904.
Shouzhi Wang Lili Li Weidong He Yongliang Shao Yanlu Li Yongzhong Wu Xiaopeng Hao 《Advanced functional materials》2020,30(27)
Binary metal oxides (such as NiCo2O4) are regarded as attractive electrode materials for advanced energy storage devices since they offer more electrochemical activity and higher capacity than monometal oxide. However, the volume expansion and low electronic conductivity are the main bottleneck seriously hindering their application. To overcome these barriers, a novel strategy that introduces a bimetallic oxynitride layer (NiCoON) with oxygen vacancy to the surface of NiCo2O4 nanowires as an anode for Li‐ion capacitors (LICs) is proposed. The oxygen vacancy on the surface and the modulation of multiple valence states are investigated by the electron paramagnetic resonance, X‐ray photoelectron spectroscopy characterization, and first‐principles calculation. Benefiting from the merits of substantially improved electrical conductivity and increased concentration of active sites, the optimized NiCoON electrode delivers remarkable capacity (1855 mAh g?1 at 0.2 A g?1) and rate performance. The LIC device assembled by NiCoON anodes and N‐doped carbon nanowire cathodes delivers excellent rate capability, high energy density (148.5 Wh kg?1), and outstanding power density (30 kW kg?1). This study provides a new pathway for developing bimetallic oxides with an improved performance in electrochemical energy storage, conversion fields, and beyond. 相似文献
905.
906.
Xin Sun Jiacheng Bao Kai Li Morris D. Argyle Gang Tan Hertanto Adidharma Kaihang Zhang Maohong Fan Ping Ning 《Advanced functional materials》2021,31(7):2006287
Plasma technology is an eco-friendly way to modify or fabricate carbon-based materials (CBMs) due to plasmas’ distinctive abilities in tuning the surface physicochemical properties by implanting functional groups or incorporating heteroatoms into the surface without changing the bulk structure. However, the mechanisms of functional groups formation on the carbon surface are still not clearly explained because of the variety of different discharge conditions and the complexity of plasma chemistry. Consequently, this paper contains a comprehensive review of plasma-treated carbon-based materials and their applications in environmental, materials, and energy fields. Plasma-treated CBMs used in these fields have been significantly enhanced in recent years because these related materials possess unique features after plasma treatment, such as higher adsorption capacity, enhanced wettability, improved electrocatalytic activity, etc. Meanwhile, this paper also summarizes possible reaction routes for the generation of functional groups on CBMs. The outlook for future research is summarized, with suggestions that plasma technology research and development shall attempt to achieve precise control of plasmas to synthesize or to modify CBMs at the atomic level. 相似文献
907.
Won-Jin Kwak Hyung-Seok Lim Peiyuan Gao Ruozhu Feng Sujong Chae Lirong Zhong Jeffrey Read Mark H. Engelhard Wu Xu Ji-Guang Zhang 《Advanced functional materials》2021,31(2):2002927
A stable electrolyte is critical for practical application of lithium–oxygen batteries (LOBs). Although the ionic conductivity and electrochemical stability of the electrolytes have been extensively investigated before, their oxygen solubility, viscosity, volatility, and the stability against singlet oxygen (1O2) still need to be comprehensively investigated to provide a full picture of the electrolytes, especially for an open system such as LOBs. Herein, a systematic investigation is reported on the localized high-concentration electrolytes (LHCEs) using different fluorinated diluents in comparison with those of conventional electrolytes. The physical properties and activation energies for reactions with singlet oxygen (1O2) of these electrolytes are calculated by density functional theory. The electrochemical performances of LOBs using these electrolytes are compared. This study reveals that the correlation between the stability of the electrolytes and their physical and electrochemical properties depends strongly on the diluents in LHCEs. Therefore, it shines light on the rational design of new electrolytes for LOBs. 相似文献
908.
Yuan Yue Ning Li Yang Ha Matthew J. Crafton Bryan D. McCloskey Wanli Yang Wei Tong 《Advanced functional materials》2021,31(14):2008696
Cation-disordered rocksalts (DRXs) have emerged as a new class of high-capacity Li-ion cathode materials. One unique advantage of the DRX chemistry is the structural flexibility that substantially lessens the elemental constraints in the crystal lattice, such as Li content, choice of transition metal redox center paired with appropriate d0 metal, and incorporation of F anion, which allows optimization of the key redox reactions. Herein, a series of the DRX oxyfluorides based on the Mn redox have been designed and synthesized. By tailoring the stoichiometry of the DRX compositions, high-capacity cycling by promoting the cationic Mn2+/Mn4+ redox reactions while suppressing those from anionic O is successfully demonstrated. A highly fluorinated DRX compound, Li1.2Mn0.625Nb0.175O1.325F0.675 (M0.625F0.675), delivers a capacity of ≈170 mAh g−1 at C/3 for 100 cycles. This work showcases the concept of balancing the cationic and anionic redox reactions in the DRX cathodes for improved electrochemical performance through the rational composition design. 相似文献
909.
Chul-Ho Jung Do-Hoon Kim Donggun Eum Kyeong-Ho Kim Jonghyun Choi Jongwon Lee Hyung-Ho Kim Kisuk Kang Seong-Hyeon Hong 《Advanced functional materials》2021,31(18):2010095
Ni-rich layered LiNixCoyMn1−x−yO2 (LNCM) with Ni content over >90% is considered as a promising lithium ion battery (LIB) cathode, attributed by its low cost and high practical capacity. However, Ni-rich LNCM inevitably suffers rapid capacity fading at a high state of charge due to the mechanochemical breakdown; in particular, the microcrack formation has been regarded as one of the main culprits for Ni-rich layered cathode failure. To address these issues, Ni-rich layered cathodes with a textured microstructure are developed by phosphorous and boron doping. Attributed by the textured morphology, both phosphorous- and boron-doped cathodes suppress microcrack formation and show enhanced cycle stability compared to the undoped cathode. However, there exists a meaningful capacity retention difference between the doped cathodes. By adapting the various analysis techniques, it is shown that the boron-doped Ni-rich layered cathode displays better cycle stability not only by its ability to suppress microcracks during cycling but also by its primary particle morphology that is reluctant to oxygen evolution. The present work reveals that not only restraint of particle cracks but also suppression of oxygen release by developing the oxygen stable facets is important for further improvements in state-of-the-art Li ion battery Ni-rich layered cathode materials. 相似文献
910.
Chaoqi Zhang Ruihu Lu Chao Liu Ling Yuan Jing Wang Yan Zhao Chengzhong Yu 《Advanced functional materials》2021,31(26):2100099
Hydrogen peroxide (H2O2) production by electrochemical two-electron water oxidation reaction (2e-WOR) is a promising approach, where high-performance electrocatalysts play critical roles. Here, the synthesis of nanostructured CaSnO3 confined in conductive carbon fiber membrane with abundant oxygen vacancy (OV) as a new generation of 2e-WOR electrocatalyst is reported. The CaSnO3@carbon fiber membrane can be directly used as a self-standing electrode, exhibiting a record-high H2O2 production rate of 39.8 µmol cm−2 min−1 and a selectivity of ≈90% (at 2.9 V vs reversible hydrogen electrode). The CaSnO3@carbon fiber membrane design improves not only the electrical conductivity and stability of catalysts but also the inherent activity of CaSnO3. Density functional theory calculation further indicates the crucial role of OV in increasing the adsorption free energy toward oxygen intermediates associated with the competitive four-electron water oxidation reaction pathway, thus enhancing the activity and selectivity of 2e-WOR. The findings pave a new avenue to the rational design of electrocatalysts for H2O2 production from water. 相似文献