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Inverse opal manganese dioxide constructed by few-layered ultrathin nanosheets as high-performance cathodes for aqueous zinc-ion batteries

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Nano Research 2019年第6期12卷 1347-1353页

作者： Hao Ren Jin Zhao Lan Yang Qinghua Liang Srinivasan Madhavi Qingyu Yan School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Energy Research Institute(ERI@N) Nanyang Technological UniversitySingapore 637553Singapore

Considering the high safety,low-cost and high capacity,aqueous zinc ion batteries have been a potential candidate for energy storage ensuring smooth electricity ***,we have synthesized inverse opal manganese dioxide constructed by few-layered ultrathin nanosheets by a solution template method at mild *** ultrathin nanosheets with the thickness as small as 1 nm are well separated without obvious *** as cathode material for aqueous zinc ion batteries,the few-layered ultrathin nanosheets combined with the inverse opal structure guarantee excellent performance.A high specific discharge capacity of 262.9 mAh·g^-1 is retained for the 100th cycle at a current density of 300 mA·g^-1 with a high capacity retention of 95.6%.A high specific discharge capacity of 121 mAh·g^-1 at a high current density of 2,000 mA·g^-1 is achieved even after 5,000 long-term *** ex-situ X-ray diffraction (XRD) patterns,selected-area electron diffraction (SAED) patterns and high-resolution transmission electron microscopy (HRTEM) results demonstrate that the discharge/charge processes involve the reversible formation of zinc sulfate hydroxide hydrate on the cathode while in-plane crystal structure of the layered bimessite MnO2 could be *** unique structured MnO2 is a promising candidate as cathode material for high capacity,high rate capability and long-term aqueous zinc-ion batteries.

关键词： inverse opal ultrathin few-layered nanosheets MnO2 zinc ion batteries

PAM-PAA microgel inverse opal photonic crystal and pH response

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Chinese Chemical Letters 2007年第11期18卷 1395-1398页

作者： Yong Qiang He Xiao Dong Wang Jian Ying Wang Yan Feng Yong Qiang Zhao Xiu Dong You School of Science Tianjin University Tianjin 300072 China Insititute of Medical Equipment Academy of Military Medical Sciences Tianjin 300161 China

The colloidal crystal template or opal with a closed-packed face-centered cubic （fcc） lattice was prepared from monodisperse polystyrene （PS） spheres by vertical sedimentation. The template provided void space for infiltration of monomer precursor composed of acrylate acid, acrylamide and ammonium-persulfate, as well as microgel from the subsequent copolymerization. The sample was immersed in dimethylbenzene for completely removing PS spheres to form PAM inverse opal hydrogels （IOHPAM） or PAM/PAA inverse opal hydrogels （IOHPAM/PAA） photonic crystals. The PS spheres were replaced by air spheres, which interconnected each other through the windows. The study of responses to pH show that there are two peaks for both IOHPAM and IOHPAM/PAA films, but the IOHPAM/PAA peaks shift to higher pH, and the peaks are independent with the AA content.

关键词： Photonic crystal pH response PAM/PAA opal Inverse opal hydrogel

Fabrication of BaTiO_3 Inverse opal Photonic Crystal

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Chinese Chemical Letters 2004年第2期15卷 228-230页

作者： AnXIANG JianPingGAO HongKuiCHEN JiuGaoYU RuiXianLIU SchoolofScience TianjinUniversityTianjin300072

The colloidal crystal template or opal with a closed-packed face centered cubic (fcc) lattice, was prepared from monodisperse polystyrene (PS) spheres by gravity sedimentation. The template was used for the generation of photonic crystal. The template provided void space for infiltration of liquid precursor composed of titanium butyloxide, barium acetate, ethanol, and acetic acid. The opal composite was hydrolyzed, dried, sintered by heating for completely removing PS spheres to form BaTiO3 photonic crystals with inverse opal structure. The PS spheres were replaced by air spheres, which interconnected each other through the windows on the BaTiO3 wall. So both the BaTiO3 wall and air void constitute continuous phases.

关键词： Photonic crystal barium titanate opal inverse opal.

Treating temperature effect on bandgap in polymer opal photonic crystals

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Chinese Science Bulletin 2002年第11期47卷 960-962页

作者： Bo Li Ji Zhou Wei Hu Longtu Li Zhilun Gui Tsing Hua Univ State Key Lab New Ceram & Fine Proc Dept Mat Sci & Engn Beijing 100084 Peoples R China

The optical reflective spectra and microstruc-tures of polystyrene opal photonic crystals treated with different temperatures have been investigated. With temperature increasing, the polystyrene spheres in opal structure transform to dodecahedrons, and the peak of reflective spectrum moves to shorter wavelength. The experiment result testifies the effect of the effective refractive index and the filling ratio to the bandgap position, and it corresponds to the theoretical simulative result.

关键词： photonic crystals opal temperature self-assemble.

Variations of opal accumulation rates and paleoproductivity over the past 12 Ma at ODP Site 1143, southern South China Sea

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Chinese Science Bulletin 2002年第7期47卷 596-598页

作者： Li Jianru Wang Rujian Li Baohua Laboratory of Marine Geology MEOTongji University200092ShanghaiChina Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences210008NanjingChina

The biogenic silica analysis was performed on 463 samples from ODP 184 Site 1143, the southern South China Sea. The results show that the opal content and MAR evidently increased between 12.3 and 5.7 Ma, which was contemporary with the high carbonate and total MARs, reflecting the high biogenic productivity in the late Miocene. This demonstrates the occurrence of the late Miocene 'Biogenic Bloom Event' in the southern South China Sea, corresponding to the late Miocene-early Pliocene 'Biogenic Bloom Event' in the Indian-Pacific Ocean. The increases of opal content and MAR after the middle Pleistocene (about 0.7 Ma) is inferred to result from the enhanced upwelling and nutrient supply, which was induced by the intensified monsoon circulation after the 'Mid-Pleistocene Revolution'.

关键词： opal MAR biogenic productivity Biogenic Bloom Event late Miocene South China Sea.

Hydrothermal Dissolution of opal in Sodium Hydroxide Lyes for the Synthesis of Water Glass

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Advances in Chemical Engineering and Science 2017年第1期7卷 76-90页

作者： Thomas Pfeiffer Dirk Enke Robert Roth Hans Roggendorf Institute of Physics Martin-Luther-University Halle-Wittenberg Halle Germany OPTERRA Zement GmbH Karsdorf Germany Institute of Chemical Technology University of Leipzig Leipzig Germany Institute of Physics Martin-Luther-University Halle-Wittenberg Halle Germany

Common opal was dissolved in NaOH lyes in rotating autoclaves. The starting material was characterized by X-ray diffraction and adsorption spectroscopy, thermal and chemical analysis, electron and atomic force microscopy. The opal proved to be an opal-CT with a microstructure consisting of microcrystalline tridymite, traces of low-quartz, and amorphous parts built up by random packings of size distributed amorphous silica colloids. The dissolution conditions have been inspired by the technological process of hydrothermal water glass synthesis by dissolving silica. Temperature and time of the dissolution process as well as initial molar SiO2:Na2O (Rm) ratios of the starting materials were varied systematically. The particle size of the samples was varied, too, but due to the nanoscopic microstructure without greater impact on dissolution kinetics. The process products were analyzed chemically. Additionally, some of them were characterized by X-ray diffraction, viscosimetry and dynamic light scattering. Already after short dissolution times, water glasses with quite high silica concentrations of up to 27 wt.% and SiO2:Na2O ratios of up to 3.7 were obtained. At longer dissolution times low-quartz and analcime precipitated and the SiO2 contents were reduced to about 22 wt.% and Rm to about 2.7. The silica contents in equilibrium with low-quartz were almost independent on temperature.

关键词： Water Glass opal Silica Hydrothermal Dissolution

Photovoltaic Properties of CdSe Quantum Dot Sensitized Inverse opal TiO<sub>2</sub>Solar Cells: The Effect of TiCl<sub>4</sub>Post Treatment

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Journal of Modern Physics 2017年第4期8卷 522-530页

作者： Motoki Hironaka Taro Toyoda Kanae Hori Yuhei Ogomi Shuzi Hayase Qing Sheng Department of Engineering Science The University of Electro-Communications Chofu Japan Graduate School of Life Science and Systems Engineering Kyushu Institute of Technology Kitakyushu Japan

Recently, semiconductor quantum dot (QD) sensitized solar cells (QDSSCs) are expected to achieve higher conversion efficiency because of the large light absorption coefficient and multiple exciton generation in QDs. The morphology of TiO2 electrode is one of the most important factors in QDSSCs. Inverse opal (IO) TiO2 electrode, which has periodic mesoporous structure, is useful for QDSSCs because of better penetration of electrolyte than conventional nanoparticulate TiO2 electrode. In addition, the ordered three dimensional structure of IO-TiO2 would be better for electron transport. We have found that open circuit voltage Voc of QDSSCs with IO-TiO2 electrodes was much higher (0.2 V) than that with nanoparticulate TiO2 electrodes. But short circuit current density Jsc was lower in the case of IO-TiO2 electrodes because of the smaller surface area of IO-TiO2. In this study, for increasing surface area of IO-TiO2, we applied TiCl4 post treatment on IO-TiO2 and investigated the effect of the post treatment on photovoltaic properties of CdSe QD sensitized IO-TiO2 solar cells. It was found that Jsc could be enhanced due to TiCl4 post treatment, but decreased again for more than one cycle treatment, which indicates excess post treatment may lead to worse penetration of electrolyte. Our results indicate that the appropriate post treatment can improve the energy conversion efficiency of the QDSSCs.

关键词： Quantum Dot Sensitized Solar Cells Inverse opal Structure TiCl4 Post Treatment Morphology of the TiO2 Electrode

Quaternary biogenic opal records in the South China Sea: Linkages to East Asian monsoon, global ice volume and orbital forcing

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Science China Earth Sciences 2007年第5期50卷 710-724页

作者： WANG RuJian JIAN ZhiMin XIAO WenShen TIAN Jun LI JianRu CHEN RongHua ZHENG YuLong CHEN JianFang State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China

Particulate fluxes investigated in the central South China Sea (SCS) during 1993―1996 indicate that opal flux can be used to show primary productivity change, which provides a foundation for tracing the evolutionary relationship between the surface productivity and East Asian monsoon in the SCS during the late Quaternary glacial and interglacial periods. Based on the studies of opal % and their mass accumulation rates (MAR) at the six sites recovered from the SCS during the “Resolution” ODP Leg 184 and “Sonne” 95 cruise of the Sino-Germany cooperation, opal % and their MARs increased evidently in the northern sites since 470―900 ka, and they enhanced and reduced, respectively, during the glacial and interglacial periods. Whereas they increased obviously in the southern sites since 420―450 ka, and they augmented and declined, respectively, during the interglacial and glacial periods. The vari- ability in opal % and their MARs in the late Quaternary glacial cyclicity indicate the “seesaw” pattern of surface productivity in the SCS. The winter monsoon intensified during the glacial periods, surface productivity increased and decreased, respectively, in the northern and southern SCS. The summer monsoon strengthened during the interglacial periods, surface productivity increased and decreased, respectively, in the southern and northern SCS. The cross spectral analyses between the opal % in the northern and southern SCS during the Quaternary and global ice volume (δ 18O) and orbital forcing (ETP) indicate that the East Asian winter and summer monsoons could be ascribed to the different drive mechanisms. On the orbital time scale, the global ice volume change could be a dominant factor for the winter monsoon intension and temporal variations. As compared with the winter monsoon, the correlative summer solar radiation with the obliquity and precession in the Northern Hemisphere could be a mostly controlling factor for the summer monsoon intension and temporal variations.

关键词： biogenic opal surface productivity East Asian monsoon global ice volume orbital forcing ODP Leg 184 Quaternary South China Sea

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反opal的形成过程及带隙特性的测量

反opal的形成过程及带隙特性的测量