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Tao Tao

Bio: Tao Tao is an academic researcher from Nanjing University. The author has contributed to research in topics: Materials science & Epitaxy. The author has an hindex of 18, co-authored 116 publications receiving 1182 citations. Previous affiliations of Tao Tao include Nanjing University of Information Science and Technology & Xiamen University.


Papers
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Journal ArticleDOI
TL;DR: In this paper, a review of the development of pristine 2D metal-organic framework (MOF) nanosheets for electrocatalytic reactions is presented, including the oxygen evolution reaction (OER), the oxygen reduction reaction (ORR), the hydrogen evolution reaction, the carbon dioxide reduction reaction, and the urea oxidation reaction.
Abstract: Due to their appealing properties such as abundant number of coordinatively unsaturated atoms, enhanced conductivity, high porosity, large surface area and tunable structure, 2D metal–organic framework (MOF) nanosheets have stimulated extensive research interest in the field of electrocatalysis. During the past several years, significant advances have been made in the direct applications of pristine 2D MOF nanosheets as efficient electrocatalysts. This review first discusses the synthetic strategies of MOF nanosheets. Then recent progress on pristine MOF nanosheets for electrocatalytic reactions, including the oxygen evolution reaction (OER), the oxygen reduction reaction (ORR), the hydrogen evolution reaction (HER), the carbon dioxide reduction reaction (CRR) and the urea oxidation reaction (UOR) is summarized. In particular, engineering electronic structures of pristine MOF nanosheets to favor efficient electrocatalytic processes are discussed. Despite the encouraging accomplishments achieved, more engineered pristine MOF nanosheets with enhanced electrocatalytic performance are still needed. Therefore, bottlenecks faced by current pristine MOF nanosheets for electrocatalysis and potential solutions to these problems are finally proposed to promote further development in this research field.

148 citations

Journal ArticleDOI
TL;DR: A novel method to immobilize hydrous zirconium oxide nanoparticle within quaternary-aminated wheat straw and obtained an inexpensive, eco-friendly nanocomposite Ws-N-Zr, which has a great potential in efficient removal of phosphate in contaminated waters.
Abstract: Advanced removal of phosphate by low-cost adsorbents from municipal wastewater or industrial effluents is an effective and economic way to prevent the occurrence of eutrophication. Here, we proposed a novel method to immobilize hydrous zirconium oxide nanoparticle within quaternary-aminated wheat straw, and obtained an inexpensive, eco-friendly nanocomposite Ws–N–Zr. The biomass-based Ws–N–Zr exhibited higher preference toward phosphate than commercial anion exchanger IRA-900 when competing sulfate ions coexisted at relatively high levels. Such excellent performance of Ws–N–Zr resulted from its specific hybrid structure, the quaternary ammonium groups bonded on the host favor the preconcentration of phosphate ions inside the wheat straw based on Donnan effect, and the encapsulated HZO nanoparticle exhibits preferable sequestration of phosphate ions through specific interaction, as further demonstrated by FTIR and X-ray photoelectron spectroscopy. Cycle adsorption and regeneration experiments demonstrated ...

122 citations

Journal ArticleDOI
TL;DR: The azo-hydrazone tautomerism of two pyridine-2,6-dione based Disperse Yellow dyes has been achieved by pH control and metal-ion complexation, respectively, which is evidenced by UV-visible spectra using pH-titration, (1)H NMR and X-ray single-crystal diffraction techniques for two dyes and one neutral dinuclear dye-metal complex.
Abstract: The azo-hydrazone tautomerism of two pyridine-2,6-dione based Disperse Yellow dyes has been achieved by pH control and metal-ion complexation, respectively, which is evidenced by UV-visible spectra using pH-titration, 1H NMR and X-ray single-crystal diffraction techniques for two dyes and one neutral dinuclear dye–metal complex. pH-titration experiments under strong and weak acidic conditions (HCl and HOAc) as well as strong and weak alkaline conditions (NaOH and ammonia) demonstrate that there is an equilibrium between the azo (HL1-A and HL2-A) and hydrazone (HL1-H and HL2-H) tautomers for two dyes in solution but the hydrazone form is dominant under conventional conditions. The hydrazone proton is also observed in the 1H NMR spectra of HL1-H and HL2-H which can be verified by the hydrogen–deuterium exchange and the presence of cooperative six-membered intramolecular hydrogen rings involving the hydrazone proton in their X-ray single-crystal structures. Moreover, the azo-hydrazone tautomerism is evidenced by the formation of a novel neutral dinuclear dye–metal complex Cu2(L2-A)4, where all the ligands are in the azo form and two types of coordination modes are present for four L2-A ligands. Namely, the side two ligands serve as the bidentate capping ligands, while the middle ones act as the quadridentate bridging ligands linking adjacent CuII centers in a reverse fashion.

91 citations

Journal ArticleDOI
TL;DR: A fully conjugated diradicaloid molecular cage is synthesized and its aromaticity was investigated, finding different types of aromaticity were accessed in one molecular cage platform, depending on the symmetry, number of π -electrons and spin state.
Abstract: Aromaticity is a vital concept that governs the electronic properties of π-conjugated organic molecules and has long been restricted to 2D systems. The aromaticity in 3D π-conjugated molecules has been rarely studied. Here we report a fully conjugated diradicaloid molecular cage and its global aromaticity at different oxidation states. The neutral compound has an open-shell singlet ground state with a dominant 38π monocyclic conjugation pathway and follows the [4n + 2] Huckel aromaticity rule; the dication has a triplet ground state with a dominant 36π monocyclic conjugation pathway and satisfies [4n] Baird aromaticity; the tetracation is an open-shell singlet with 52 π-electrons that are delocalized along the 3D rigid framework, showing 3D global antiaromaticity; and the hexacation possesses D3 symmetry with 50 globally delocalized π-electrons, showing [6n + 2] 3D global aromaticity. Different types of aromaticity were therefore accessed in one molecular cage platform, depending on the symmetry, number of π-electrons and spin state. A conjugated diradicaloid cage has been synthesized and its aromaticity was investigated. The neutral compound and the dication have dominant monocyclic conjugation pathways and both are aromatic (the former following Huckel’s rule and the latter Baird’s rule). The tetracation ([6n + 4] π-electrons) exhibits global 3D antiaromaticity whereas the hexacation ([6n + 2] π-electrons) exhibits global 3D aromaticity and has high D3 symmetry.

85 citations

Journal ArticleDOI
TL;DR: Four derivatives of two azulene-fused s-indacene isomers show larger radical character than the respective ones of DAI-1, and all experimental and theoretical analyses disclose a shift of local (anti)aromaticity along the backbone, with two aromatic tropylium rings at the termini.
Abstract: Non-alternant, non-benzenoid π-conjugated polycyclic hydrocarbons (PHs) are expected to exhibit very different electronic properties from all-benzenoid PHs. Reported herein are the syntheses and physical properties of four derivatives of two azulene-fused s-indacene isomers, the diazuleno[2,1-a:2',1'-g]-s-indacene (DAI-1) and diazuleno[2,1-a:1',2'-h]-s-indacene (DAI-2). The backbone of both isomers contains 28π electrons and is a 7-5-5-6-5-5-7 fused ring system. X-ray crystallographic analysis, NMR spectra, and theoretical calculations (ACID, NICS) reveal a structure with two aromatic azulene units fused with a central anti-aromatic s-indacene moiety. All compounds exhibit open-shell diradical character and are magnetically active, but the derivatives of DAI-2 show larger radical character than the respective ones of DAI-1. Their dications were isolated in crystalline form and all experimental and theoretical analyses disclose a shift of local (anti)aromaticity along the backbone, with two aromatic tropylium rings at the termini.

53 citations


Cited by
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Journal ArticleDOI
01 Jan 2020-Heliyon
TL;DR: This work has presented a very detailed review of the different classified azo dyes as a function of the number of azo groups and the appropriate functional groups and pointed out some chemical properties of these dyes such as reactivity, isomerization and tautomerism.

375 citations

Journal ArticleDOI
TL;DR: The most fundamental aspects of selective phosphate removal processes are discussed and gains from the latest developments of phosphate-selective sorbents are highlighted, along with a discussion of some overlooked facts regarding the development of high-performance sor bents for selective phosphate Removal from water and wastewater.
Abstract: Eutrophication of water bodies is a serious and widespread environmental problem. Achieving low levels of phosphate concentration to prevent eutrophication is one of the important goals of the wastewater engineering and surface water management. Meeting the increasingly stringent standards is feasible in using a phosphate-selective sorption system. This critical review discusses the most fundamental aspects of selective phosphate removal processes and highlights gains from the latest developments of phosphate-selective sorbents. Selective sorption of phosphate over other competing anions can be achieved based on their differences in acid-base properties, geometric shapes, and metal complexing abilities. Correspondingly, interaction mechanisms between the phosphate and sorbent are categorized as hydrogen bonding, shape complementarity, and inner-sphere complexation, and their representative sorbents are organic-functionalized materials, molecularly imprinted polymers, and metal-based materials, respectively. Dominating factors affecting the phosphate sorption performance of these sorbents are critically examined, along with a discussion of some overlooked facts regarding the development of high-performance sorbents for selective phosphate removal from water and wastewater.

339 citations

Journal ArticleDOI
TL;DR: In this article, the authors provide an overview of different aspects of 2D MOF layered architectures such as topology, interpenetration, structural transformations, properties, and applications.
Abstract: Among the recent developments in metal-organic frameworks (MOFs), porous layered coordination polymers (CPs) have garnered attention due to their modular nature and tunable structures. These factors enable a number of properties and applications, including gas and guest sorption, storage and separation of gases and small molecules, catalysis, luminescence, sensing, magnetism, and energy storage and conversion. Among MOFs, two-dimensional (2D) compounds are also known as 2D CPs or 2D MOFs. Since the discovery of graphene in 2004, 2D materials have also been widely studied. Several 2D MOFs are suitable for exfoliation as ultrathin nanosheets similar to graphene and other 2D materials, making these layered structures useful and unique for various technological applications. Furthermore, these layered structures have fascinating topological networks and entanglements. This review provides an overview of different aspects of 2D MOF layered architectures such as topology, interpenetration, structural transformations, properties, and applications.

300 citations

Posted Content
01 Feb 2020-viXra
TL;DR: In this article, the authors discuss strategies to achieve high C2+ selectivity through rational design of the catalyst and electrolyte, focusing on findings extracted from in situ and operando characterizations.
Abstract: CO2 electroreduction reaction (CO2RR) to fuels and feedstocks is an attractive route to close the anthropogenic carbon cycle and store renewable energy. The generation of more reduced chemicals, especially multicarbon oxygenate and hydrocarbon products (C2+) with higher energy density is highly desirable for industrial applications. However, selective conversion of CO2 to C2+ suffers from high overpotential, low reaction rate and low selectivity, and the process is extremely sensitive to the catalyst structure and electrolyte. Here we discuss strategies to achieve high C2+ selectivity through rational design of the catalyst and electrolyte. Current state-of-the-art catalysts, including Cu and Cu-bimetallic catalysts as well as alternative materials are considered. The importance of taking into consideration the dynamic evolution of the catalyst structure and composition are highlighted, focusing on findings extracted from in situ and operando characterizations. Additional theoretical insight into the reaction mechanisms underlying the improved C2+ selectivity of specific catalyst geometries/compositions in synergy with a well-chosen electrolyte are also provided.

259 citations

Journal ArticleDOI
TL;DR: In this paper, the fundamental understanding of the semiconductor physics and chemistry of Ga2O3 in terms of electronic band structures, optical properties, and the chemistry of defects and impurity doping is provided.
Abstract: Gallium oxide (Ga2O3) is an emerging wide bandgap semiconductor that has attracted a large amount of interest due to its ultra-large bandgap of 4.8 eV, a high breakdown field of 8 MV/cm, and high thermal stability. These properties enable Ga2O3 a promising material for a large range of applications, such as high power electronic devices and solar-blind ultraviolet (UV) photodetectors. In the past few years, a significant process has been made for the growth of high-quality bulk crystals and thin films and device optimizations for power electronics and solar blind UV detection. However, many challenges remain, including the difficulty in p-type doping, a large density of unintentional electron carriers and defects/impurities, and issues with the device process (contact, dielectrics, and surface passivation), and so on. The purpose of this article is to provide a timely review on the fundamental understanding of the semiconductor physics and chemistry of Ga2O3 in terms of electronic band structures, optical properties, and chemistry of defects and impurity doping. Recent progress and perspectives on epitaxial thin film growth, chemical and physical properties of defects and impurities, p-type doping, and ternary alloys with In2O3 and Al2O3 will be discussed.

240 citations