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881.
Hien Thi Thu Pham Yeongsu Kim Young‐Jun Kim Jong‐Won Lee Min‐Sik Park 《Advanced functional materials》2019,29(31)
Given that the performance of a lithium–oxygen battery (LOB) is determined by the electrochemical reactions occurring on the cathode, the development of advanced cathode nanoarchitectures is of great importance for the realization of high‐energy‐density, reversible LOBs. Herein, a robust cathode design is proposed for LOBs based on a dual‐phasic carbon nanoarchitecture. The cathode is composed of an interwoven network of porous metal–organic framework (MOF) derived carbon (MOF‐C) and conductive carbon nanotubes (CNTs). The dual‐phasic nanoarchitecture incorporates the advantages of both components: MOF‐C provides a large surface area for the oxygen reactions and a large pore volume for Li2O2 storage, and CNTs provide facile pathways for electron and O2 transport as well as additional void spaces for Li2O2 accommodation. It is demonstrated that the synergistic nanoarchitecturing of the dual‐phasic MOF‐C/CNT material results in promising electrochemical performance of LOBs, as evidenced by a high discharge capacity of ≈10 050 mAh g?1 and a stable cycling performance over 75 cycles. 相似文献
882.
Chengan Liao Baopeng Yang Ning Zhang Min Liu Guoxin Chen Xiaoming Jiang Gen Chen Junliang Yang Xiaohe Liu Ting‐Shan Chan Ying‐Jui Lu Renzhi Ma Wei Zhou 《Advanced functional materials》2019,29(40)
Combining transition metal oxide catalysts with conductive carbonaceous material is a feasible way to improve the conductivity. However, the electrocatalytic performance is usually not distinctly improved because the interfacial resistance between metal oxides and carbon is still large and thereby hinders the charge transport in catalysis. Herein, the conductive interface between poorly conductive NiO nanoparticles and semi‐conductive carbon nitride (CN) is constructed. The NiO/CN exhibits much‐enhanced oxygen evolution reaction (OER) performance than corresponding NiO and CN in electrolytes of KOH solution and phosphate buffer saline, which is also remarkably superior over NiO/C, commercial RuO2, and mostly reported NiO‐based catalysts. X‐ray photoelectron spectroscopy and extended X‐ray absorption fine structure spectrum reveal that a metallic Ni–N bond is formed between NiO and CN. Density functional theory calculations suggest that NiO and CN linked by a Ni–N bond possess a low Gibbs energy for OER intermediate adsorptions, which not only improves the transfer of charge but also promotes the transmission of mass in OER. The metal–nitrogen bonded conductive and highly active interface pervasively exists between CN and other transition metal oxides including Co3O4, CuO, and Fe2O3, making it promising as an inexpensive catalyst for efficient water splitting. 相似文献
883.
Bo‐Quan Li Shu‐Yuan Zhang Xiang Chen Chen‐Yu Chen Zi‐Jing Xia Qiang Zhang 《Advanced functional materials》2019,29(29)
Organic framework materials constructed by covalently linking organic building blocks into framework structures are highly regarded as paragons to precisely control the material structure at the atomic level. Herein, a direct synthesis methodology is proposed as a guidance for the bulk synthesis of organic framework materials. Framework porphyrin (POF) materials are one‐pot synthesized to demonstrate the advances of the direct synthesis methodology. The as‐synthesized POF materials are intrinsically 2D and exhibit impressive versatility in composition, structure, morphology, and function, delivering a free‐standing POF film, hybrids of POF and nanocarbon, and cobalt‐coordinated POF. When applied as electrocatalysts for oxygen reduction reaction and oxygen evolution reaction, the cobalt‐coordinated POF exhibits excellent bifunctional electrocatalytic performances comparable with noble‐metal‐based electrocatalysts. The direct synthesis methodology and resultant POF materials demonstrate the ability of controlling materials at the atomic level for energy electrocatalysis. 相似文献
884.
Qian Lu Jie Yu Xiaohong Zou Kaiming Liao Peng Tan Wei Zhou Meng Ni Zongping Shao 《Advanced functional materials》2019,29(38)
The self‐catalyzed growth of nanostructures on material surfaces is one of the most time‐ and cost‐effective ways to design multifunctional catalysts for a wide range of applications. Herein, the use of this technique to develop a multicomponent composite catalyst with CoSx core encapsulated in an ultrathin porous carbon shell entangled with Co, N‐codoped carbon nanotubes is reported. The as‐prepared catalyst has a superior catalytic activity for oxygen evolution and oxygen reduction reactions, an ultralow potential gap of 0.74 V, and outstanding durability, surpassing most previous reports. Such superiority is ascribed, in part, to the unique 3D electrode architecture of the composite, which is favorable for transporting oxygen species and electrons and creates a synergy between the components with different functionalities. Moreover, the flexible solid Zn–air battery assembled with such an air electrode shows a steady discharge voltage plateau of 1.25 V and a round‐trip efficiency of 70% at 1 mA cm?2. This work presents a simple strategy to design highly efficient bifunctional oxygen electrocatalysts and may pave the way for the practical application of these materials in many energy conversion/storage devices. 相似文献
885.
886.
Yangyang Xu Peilin Deng Guangda Chen Jinxi Chen Ya Yan Kai Qi Hongfang Liu Bao Yu Xia 《Advanced functional materials》2020,30(6)
The rational construction of efficient bifunctional oxygen electrocatalysts is of immense significance yet challenging for rechargeable metal–air batteries. Herein, this work reports a metal–organic framework derived 2D nitrogen‐doped carbon nanotubes/graphene hybrid as the efficient bifunctional oxygen electrocatalyst for rechargeable zinc–air batteries. The as‐obtained hybrid exhibits excellent catalytic activity and durability for the oxygen electrochemical reactions due to the synergistic effect by the hierarchical structure and heteroatom doping. The assembled rechargeable zinc–air battery achieves a high power density of 253 mW cm?2 and specific capacity of 801 mAh gZn?1 with excellent cycle stability of over 3000 h at 5 mA cm?2. Moreover, the flexible solid‐state rechargeable zinc–air batteries assembled by this hybrid oxygen electrocatalyst exhibits a high discharge power density of 223 mW cm?2, which can power 45 light‐emitting diodes and charge a cellphone. This work provides valuable insights in designing efficient bifunctional oxygen electrocatalysts for long‐life metal–air batteries and related energy conversion technologies. 相似文献
887.
Jiale Xia Hongyang Zhao Bolong Huang Lingling Xu Meng Luo Jianwei Wang Feng Luo Yaping Du Chun‐Hua Yan 《Advanced functional materials》2020,30(9)
Owing to the unique electronic properties, rare‐earth modulations in noble‐metal electrocatalysts emerge as a critical strategy for a broad range of renewable energy solutions such as water‐splitting and metal–air batteries. Beyond the typical doping strategy that suffers from synthesis difficulties and concentration limitations, the innovative introduction of rare‐earth is highly desired. Herein, a novel synthesis strategy is presented by introducing CeO2 support for the nickel–iron–chromium hydroxide (NFC) to boost the oxygen evolution reaction (OER) performance, which achieves an ultralow overpotential at 10 mA cm?2 of 230.8 mV, the Tafel slope of 32.7 mV dec?1, as well as the excellent durability in alkaline solution. Density functional theory calculations prove the established d–f electronic ladders, by the interaction between NFC and CeO2, evidently boosts the high‐speed electron transfer. Meanwhile, the stable valence state in CeO2 preserves the high electronic reactivity for OER. This work demonstrates a promising approach in fabricating a nonprecious OER electrocatalyst with the facilitation of rare‐earth oxides to reach both excellent activity and high stability. 相似文献
888.
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
889.
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
890.
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