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91.
Kaiping Zhu Liyun Wu Can Guo Jun Pu Yang Liu Xiang Chen Yuting Chen Pan Xue Jie Han Yagang Yao 《Advanced functional materials》2023,33(47):2305098
Zn metal batteries have garnered considerable scientific and technological interests. However, the widespread commercial application of these batteries is impeded by the uncontrollable dendrite growth and consequent severe side effects. Herein, a functionalized separator is prepared by spraying polyaniline-modified graphene oxide (denoted as NPGO)/polyvinylidene difluoride solution directly on one side of a common separator of glass fibers (GFs). The reversible transition between protonated and deprotonated states of quinolone imide on NPGO nanosheets can facilitate the rapid desolvation and transfer of Zn2+. Therefore, the spatial electric field as well as the Zn2+ flux is effectively homogenized due to the ion-sieving effect of NPGO nanosheets that are oriented toward Zn anode. This engineering design of the NPGO@GFs separator harvests excellent rate and cycling performance (over 3000 cycles at 20 mA cm−2) for Zn metal symmetric batteries. Meanwhile, it provides an impressive commercial prospect (500 cycles with a capacity retention of 91.6% under 2000 mA g−1) for MnO2||Zn full batteries. Such a strategy can be generalized as a common way to protect metal anodes (Na, Zn, and K) in rechargeable batteries, which is highly cost-effective and scalable. 相似文献
92.
Anees A. Ansari M. A. M. Khan M. Naziruddin Khan Salman A. Alrokayan M. Alhoshan M. S. Alsalhi 《半导体学报》2011,32(4):043001-6
This paper reports the optical and electrical properties of electrochemically deposited polyaniline (PANI)-cerium oxide (CeO2) hybrid nano-composite film onto indium-tin-oxide (ITO) glass substrate. UV–visible spectroscopy and I-V characteristic were performed to study the optical and electrical parameters of the electrochemically deposited film. The film exhibited a strong absorption below 400 nm (3.10 eV) with a well defined absorbance peak at around 285nm (4.35 eV). The estimated band gap of the CeO2 sample was 3.44 eV and this value is higher than bulk CeO2 powder (Eg = 3.19 eV) due to quantum confinement effect. 相似文献
93.
Hollow Multishelled Structure of Heterogeneous Co3O4–CeO2−x Nanocomposite for CO Catalytic Oxidation
Huan Wang Dan Mao Jian Qi Qinghua Zhang Xiaohong Ma Shuyan Song Lin Gu Ranbo Yu Dan Wang 《Advanced functional materials》2019,29(15)
Herein, hollow multishelled structure (HoMS) of Co3O4–CeO2?x nanocomposites with controllable molar ratio of Co and Ce elements is synthesized by a general strategy sequential templating approach (STA) with a facile and efficient electrostatic spray process. As a catalyst of carbon monoxide (CO) catalytic oxidation, Co3O4–CeO2?x (Co/Ce = 4/1) HoMS achieves good catalytic activity (complete conversion temperature is 166.9 °C) and stability (100 h). This performance is attributed to synergistic effects between the two components. The combination of Co3O4 and CeO2 not only generates more interfaces of Co3O4–CeO2?x, which is more favorable for the activation of oxygen, but also improves the oxidizability of Co3O4 as well as the capacity of oxygen storage of CeO2. In addition, the relatively larger effective specific surface area of the HoMS can provide more active sites, while the unique structure of HoMS can facilitate gas diffusion and maintain structural stability. 相似文献
94.
Large‐scale Synthesis of Urchin‐like Mesoporous TiO2 Hollow Spheres by Targeted Etching and Their Photoelectrochemical Properties 下载免费PDF全文
Jia Hong Pan Xing Zhu Wang Qizhao Huang Chao Shen Zhen Yu Koh Qing Wang Astrid Engel Detlef W. Bahnemann 《Advanced functional materials》2014,24(1):95-104
A versatile targeted etching strategy is developed for the large‐scale synthesis of urchin‐like mesoporous TiO2 hollow spheres (UMTHS) with tunable particle size. Its key feature is the use of a low‐temperature hydrothermal reaction of surface‐fluorinated, amorphous, hydrous TiO2 solid spheres (AHTSS) under the protection of a polyvinylpyrrolidone (PVP) coating. With the confinement of PVP and water penetration, the highly porous AHTSS are selectively etched and hollowed by fluoride without destroying their spherical morphology. Meanwhile TiO2 hydrates are gradually crystallized and their growth is preferentially along anatase (101) planes, reconstructing an urchin‐like shell consisting of numerous radially arranged single‐crystal anatase nanothorns. Complex hollow structures, such as core–shell and yolk–shell structures, can also be easily synthesized via additional protection of the interior by pre‐filling AHTSS with polyethylene glycol (PEG). The hollowing transformation is elucidated by the synergetic effect of etching, PVP coating, low hydrothermal reaction temperature, and the unique microstructure of AHTSS. The synthesized UMTHS with a large surface area of up to 128.6 m2 g‐1 show excellent light‐harvesting properties and present superior performances in photocatalytic removal of gaseous nitric oxide (NO) and photoelectrochemical solar energy conversion as photoanodes for dye‐sensitized mesoscopic solar cells. 相似文献
95.
Synergistic Sonodynamic/Chemotherapeutic Suppression of Hepatocellular Carcinoma by Targeted Biodegradable Mesoporous Nanosonosensitizers 下载免费PDF全文
Zhenli Li Jun Han Luodan Yu Xiaoqin Qian Hao Xing Han Lin Mengchao Wu Tian Yang Yu Chen 《Advanced functional materials》2018,28(26)
Hepatocellular carcinoma (HCC) is one of the deadliest malignancies worldwide featured with the poor prognosis and high mortality in affected patients. Given its insensitivity to conventional systemic chemotherapy, the development of novel modalities for HCC management is highly urgent. Sonodynamic therapy (SDT) has gained considerable momentum in cancer therapy. Especially, through synergistic SDT/chemotherapy, SDT would enhance the chemotherapeutic process on inhibiting tumor growth, which holds great potential on combating HCC. In this work, we report on the design/fabrication of targeted biodegradable nanosonosensitizers based on hollow mesoporous organosilica nanoparticles (HMONs), followed by pore‐engineering including covalent anchoring of protoporphyrin (PpIX, HMONs‐PpIX) and conjugation of arginine‐glycine‐aspartic acid in order to specifically targeting HCC cells. Such nanosonosensitizers provide efficient loading and controllable stimuli‐responsive release of chemotherapeutic agents for HCC‐targeting chemotherapy, thus promoting an enhancing chemotherapeutic process via the unique sonotoxicity under ultrasound irradiation. The HMONs matrix with biologically active organic groups in the framework (disulfide bond) are endowed with intrinsic tumor microenvironment‐responsive biodegradability and improved biocompatibility/biosafety. In particular, a synergistic inhibition effect of drug‐loaded HMONs‐PpIX‐arginine‐glycine‐aspartic acid on HCC growth has been systematically demonstrated both in vitro and in vivo (84.7% inhibition rate), which brings insights and meets the versatile therapeutic requirements for HCC management. 相似文献
96.
Hollow Cu nano/microstructures are prepared by reduction of CuSO4 · 5 H2O with glucose by using a mild hydrothermal process. The X‐ray powder diffraction and energy‐dispersive X‐ray analysis indicate that the products are pure Cu and of cubic phase. The morphology of the products can be controlled between nanotubes and microspheres assembled from hollow nanoparticles by adjusting the concentration of sodium dodecyl sulfate. A series of experiments confirm that the concentration of the glucose and NaOH also play important roles in the formation of the hollow Cu nano/microstructures. 相似文献
97.
98.
Zhongliang Huang Longlong Fan Feigang Zhao Bin Chen Kaiji Xu Shu‐Feng Zhou Jinli Zhang Qingbiao Li Dan Hua Guowu Zhan 《Advanced functional materials》2019,29(42)
Hybrid metal oxides with multilayered structures exhibit unique physical and chemical properties, particularly important to heterogeneous catalysis. However, regulations of morphology, spatial location, and shell numbers of the hybrid metal oxides still remain a challenge. Herein, binary Co3O4/ZnO nanocages with multilayered structures (up to eight layers) are prepared via chemical transformation from diverse Matryoshka‐type zeolitic imidazolate frameworks (ZIFs) via a straightforward and scalable calcination method. More importantly, the obtained ZIF‐derived metal oxides (ZDMOs) with versatile layer numbers exhibit remarkable catalytic activity for both gas‐phase CO oxidation and CO2 hydrogenation reactions, which are directly related to the sophisticated shell numbers (i.e., Co3O4‐terminated layers or ZnO‐terminated layers). Particularly, in situ reflectance infrared Fourier transform spectroscopy (DRIFTS) results indicate that the promotional effects of the multilayered structures indeed exist in CO2 hydrogenation, wherein the key reaction intermediates are quite different for five‐layer and six‐layer ZDMOs. For instance, *HCOO is the predominant intermediate over the six‐layer ZDMO; on the contrary, *H3CO is the crucial species over the five‐layer ZDMO. The ZnO/Co3O4 interface should be the active sites for CO2 hydrogenation to *HCOO and *H3CO species, which are ultimately converted to the products (CH4 or methanol). Accordingly, the work here provides a convenient way to facilely engineer multilayered Co3O4/ZnO nanocomposites with precisely controlled shell numbers for heterogeneous catalysis applications. 相似文献
99.
Pan Xue Can Guo Nanyang Wang Kaiping Zhu Shuang Jing Shuo Kong Xiaojie Zhang Li Li Hongpeng Li Yongbao Feng Wenbin Gong Qiulong Li 《Advanced functional materials》2021,31(50):2106417
Aqueous rechargeable zinc–metal batteries are a promising candidate for next-generation energy storage devices due to their intrinsic high capacity, low cost, and high safety. However, uncontrollable dendrite formation is a serious problem, resulting in limited lifespan and poor coulombic efficiency of zinc–metal anodes. To address these issues, a 3D porous hollow fiber scaffold with well-dispersed TiO2, SiO2, and carbon is used as superzincophilic host materials for zinc anodes. The amorphous TiO2 and SiO2 allow for controllable nucleation and deposition of metal Zn inside the porous hollow fiber even at ultrahigh current densities. Furthermore, the as-fabricated interconnected conductive hollow SiO2 and TiO2 fiber (HSTF) possess high porosity, high conductivity, and fast ion transport. Meanwhile, the HSTF exhibits remarkable mechanical strength to sustain massive Zn loading during repeated cycles of plating/stripping. The HSTF with interconnected conductive network can build a uniform electric field, redistributing the Zn2+ ion flux and resulting in smooth and stable Zn deposition. As a result, in symmetrical cells, the Zn@HSTF electrode delivers a long cycle life of over 2000 cycles at 20 mA cm−2 with low overpotential (≈160 mV). The excellent cycling lifespan and low polarization are also realized in Zn@HSTF//MnO2 full cells. 相似文献
100.
Enhanced Electrochromism with Rapid Growth Layer‐by‐Layer Assembly of Polyelectrolyte Complexes 下载免费PDF全文
Mengqi Cui Wee Siang Ng Xu Wang Peter Darmawan Pooi See Lee 《Advanced functional materials》2015,25(3):401-408
In this work, a facile method to deposit fast growing electrochromic multilayer films with enhanced electrochemical properties using layer‐by‐layer (LbL) self‐assembly of complex polyelectrolyte is demonstrated. Two linear polymers, poly(acrylic acid) (PAA) and polyethylenimine (PEI), are used to formulate stable complexes under specific pH to prepare polyaniline (PANI)/PAA‐PEI multilayer films via LbL deposition. By introducing polymeric complexes as building blocks, [PANI/PAA‐PEI]n films grow much faster compared with [PANI/PAA]n films, which are deposited under the same condition. Unlike the compact [PANI/PAA]n films, [PANI/PAA‐PEI]n films exhibit porous structure that is beneficial to the electrochemical process and leads to improved electrochromic properties. An enhanced optical modulation of 30% is achieved with [PANI/PAA‐PEI]30 films at 630 nm compared with the lower optical modulation of 11% measured from [PANI/PAA]30 films. The switching time of [PANI/PAA‐PEI]30 films is only half of that of [PANI/PAA]30 films, which indicates a faster redox process. Utilizing polyelectrolyte complexes as building blocks is a promising approach to prepare fast growing LbL films for high performance electrochemical device applications. 相似文献