石墨炔衍生物的合成与应用

石墨炔是由sp和sp²两种杂化碳构成的新型二维碳同素异形体。基于石墨炔化学合成规律和独特优势,利用其他芳炔前体替代六乙炔基苯,可以获得结构特异、尺寸可控的石墨炔基衍生物,而局域碳骨架的改变可以实现石墨炔衍生物性能调控,包括电导率、带隙、迁移率、空腔尺寸和电荷分离等。这类具有优良半导体性能的石墨炔基衍生物可以广泛应用于电化学储能、电催化、光电转换器件、非线性光学等诸多领域。本文主要综述了近年来石墨炔衍生物的优化设计、结构表征和光电性能,并对其代表性应用进行了总结和展望。     

Formation of colloidal CuO nanocrystallites and their spherical aggregation and reductive transformation to hollow Cu2O nanospheres

In this work, we demonstrate that cuprous oxide Cu(2)O nanospheres with hollow interiors can be fabricated from a reductive conversion of aggregated CuO nanocrystallites without using templates. A detailed process mechanism has been revealed: (i) formation of CuO nanocrystallites; (ii) spherical aggregation of primary CuO crystallites; (iii) reductive conversion of CuO to Cu(2)O; and (iv) crystal aging and hollowing of Cu(2)O nanospheres. In this template-free process, Ostwald ripening is operative in (iv) for controlling crystallite size in shell structures and thus for precisely tuning the optical band gap energy (E(g)) of resultant semiconductor nanostructures. For the first time, a wealth of colorful Cu(2)O hollow nanospheres (outer diameters in 100-200 nm), with variable E(g) in the range of 2.405-2.170 eV, has been fabricated via this novel chemical route. Considering their unique hollow structure and facile tuning in band gap energy, the prepared Cu(2)O hollow spheres can be potentially useful for harvesting solar energy in the visible range. Possibility of fabrication of Cu-Cu(2)O nanocomposites has also been discussed.     

Conversion of CuO Nanoplates into Porous Hybrid Cu2O/Polypyrrole Nanoflakes through a Pyrrole‐Induced Reductive Transformation Reaction

Porous hybrid Cu₂O/polypyrrole nanoflakes have been synthesized from solid CuO nanoplate templates through the pyrrole‐induced reductive transformation reaction at elevated temperature. The conversion mechanism involves the reductive transformation of CuO to Cu₂O and the in situ oxidative polymerization of pyrrole to polypyrrole. In addition, the morphology of the as‐converted nanohybrids depends on the shape of the CuO precursors. The strategy enables us to transform single‐crystalline CuO nanosheets into hollow hybrid Cu₂O/polypyrrole nanoframes. The ability to transform CuO and an organic monomer into porous hybrid materials of conducting polymer and Cu₂O with macrosized morphological retention opens up interesting possibilities to create novel nanostructures. Electrochemical examinations show that these porous hybrid Cu₂O/polypyrrole nanostructures exhibit efficient catalytic activity towards oxygen reduction reaction (ORR), excellent methanol tolerance ability, and catalytic stability in alkaline solution, thus making them promising nonprecious‐metal‐based catalysts for ORR in alkaline fuel cells and metal–air batteries.     

担载CuO基催化剂上2,4-二氯酚的有效氧化降解

研究了2,4-二氯酚的催化氧化降解.结果表明,CuO/y-Al2O3催化剂表现出较高的活性,且碱土金属氧化物助剂的添加可进一步显著提高2,4-二氯酚氯离子的释放率,其中以SrO的促进作用最强,该催化剂循环使用3次,2,4-二氯酚转化率及氯离子的释放率均维持100％.X射线衍射和NH3程序升温脱附结果表明,催化剂上CuO...     

Template Based Synthesis of Porous Graphdiyne Nanosheet for Reversible and Fast NO2 Detection by UV Irradiation

Two-dimensional graphdiyne (GDY) formed by sp and sp² hybridized carbon has been found to be an efficient toxic gas sensing material by density functional theory (DFT). However, little experimental research concerning its gas sensing capability has been reported owing to the complex preparation process and harsh experimental conditions. Herein, porous GDY nanosheets are successfully synthesized through a facile solvothermal synthesis technique by using CuO microspheres (MSs) as both template and source of catalyst. The porous GDY nanosheets exhibit a broadband optical absorption, rendering it suitable for the light-driven optoelectronic gas sensing applications. The GDY-based gas sensor was demonstrated to have excellent reversible to NO₂ behaviors at 25 °C for the first time. More importantly, higher response value and faster response-recovery time once exposed to NO₂ gas molecules are achieved by the illumination of UV light. In this way, our work paves the way for the exploration of GDY-based gas detection experimentally.     

Graphdiyne: Bridging SnO2 and Perovskite in Planar Solar Cells

The matching of charge transport layer and photoactive layer is critical in solar energy conversion devices, especially for planar perovskite solar cells based on the SnO₂ electron‐transfer layer (ETL) owing to its unmatched photogenerated electron and hole extraction rates. Graphdiyne (GDY) with multi‐roles has been incorporated to maximize the matching between SnO₂ and perovskite regarding electron extraction rate optimization and interface engineering towards both perovskite crystallization process and subsequent photovoltaic service duration. The GDY doped SnO₂ layer has fourfold improved electron mobility due to freshly formed C?O σ bond and more facilitated band alignment. The enhanced hydrophobicity inhibits heterogeneous perovskite nucleation, contributing to a high‐quality film with diminished grain boundaries and lower defect density. Also, the interfacial passivation of Pb?I anti‐site defects has been demonstrated via GDY introduction.     

Heteroatom Doped Graphdiyne and Analogues:Synthesis,Structures and Applications

As a new carbon allotrope,graphdiyne(GDY)has shown intensive practical application prospects in the energy field,catalysis,gas separation,etc.,due to its unique 2D π-conjugated structure,rich sp-hybridized carbon atoms and semiconductor characteristics.Considerable efforts have been made to the development of well-defined GDY materials in recent years.The doping heteroatoms can further tune the structures,semiconductor properties of GDY,and expand the promising applications.This review summarized a comprehensive development of heteroatom doped GDYs,including their synthesis,structures,properties,applications in nanotechnology,as well as the forecast in the future.     

Bacteriostatic effect of 4,7-dicyanobenzofurazan due to inactivation of 2,3-dihydroxyisovalerate dehydratase.

As part of our research on benzofurazans (BZs), we have reported the bacterioses of BZs in Escherichia coli, which may be due to O2-. produced within E. coli in the presence of dioxygen (O2). Incubation of E. coli with 4,7-dicyanobenzofurazan (1) lowered the 2,3-dihydroxyisovalerate dehydratase activity detectable in extracts from these cells. Addition of branched chain amino acids such as valine and leucine protected E. coli from growth inhibition by compound 1, though it could not protect E. coli from the damage by paraquat (PQ). Addition of Fe(III)-tris[N-(2-pyridylmethyl)-2-aminoethyl]amine (Fe-TPAA), a novel superoxide dismutase mimic, protected the dehydratase in a dose-dependent manner, which confirms that inactivation of the dehydratase is largely due to production of O2-.. The possibility was discussed that the bacteriostatic effect of compound 1 is due to the inactivation of 2,3-dihydroxyisovalerate dehydratase.     

氧化铈稳定的CuO簇在CO,C3H6和NO消除中的催化性能（英文）

研究了CuO与γ-Al2O3和CeO2的相互作用,并由此制备出能有效脱除CO,C3H6和NO的催化剂,考察了不同载体表面CuO簇的分散稳定性和耐老化性能.结果发现,随CuO负载量的增加,CuO簇因与CeO2载体的强相互作用而稳定存在;而在γ-Al2O3表面,CuO簇易聚集成较大的颗粒.另一方面,由于CeO2本身较差的热稳定性,表面分散的CuO在950oC高温处理后烧结.因此,基于γ-Al2O3载体优越的耐老化性能,在γ-Al2O3载体分散CeO2,然后再担载CuO,从而得到了稳定的CuO簇,所得催化剂比CuO/γ-A12O3和CuO/CeO2具有更好的催化性能和抗热老化性能.     

通过氧化改性提高载银活性炭的抗菌性能

使用浓HNO3和浓H2O2对活性炭进行常温氧化改性,用FTIR和N2吸附法对活性炭进行表面分析,用AAS、SEM、XRD研究银在活性炭表面的吸附和分布特征,并研究了载银活性炭的抗茵性能.结果表明,活性炭经浓HNO3常温改性后,比表面积提高,而经浓H2O2常温改性后,比表面积略有下降,但都使活性炭表面含氧基团增加.改性后,活性炭表面增加的含氧基团为[Ag(NH3)2] 的还原吸附提供更多的活性点,使银的吸附量增大5倍多,银颗粒更加密集,大小更加均一.研究表明,载银活性炭具有明显的抗茵作用,其中对金黄色葡萄球菌的杀灭效果优于对大肠杆菌的杀灭效果,氧化改性使载银活性炭抗茵作用显著增强,其中硝酸改性现象更加明显.     

Synergistic effects of CuO and Au nanodomains on Cu2O cubes for improving photocatalytic activity and stability

Cu₂O is a promising photocatalyst, but it suffers from poor photocatalytic activity and stability, especially for Cu₂O cubes. Herein, we report the deposition of CuO and Au nanodomains on Cu₂O cubes to form dual surface heterostructures (HCs) to improve photocatalytic activity and stability. The apparent quantum efficiency of Au/CuO/Cu₂O HCs was ca. 123 times that of pristine Cu₂O. In addition, the Au/CuO/Cu₂O HCs maintained nearly 80% of its original activity after eight cycles in contrast to five cycles for the Au/Cu₂O material. Therefore, CuO and Au domains greatly improved the photocatalytic activity and stability of the Cu₂O cubes due to the synergistic effect of the HCs.     

Confined Interfacial Synthesis of Highly Crystalline and Ultrathin Graphdiyne Films and Their Applications for N2 Fixation

Graphdiyne (GDY), as a new carbon allotrope, possessing both sp- and sp²-hybridized carbon atoms, has attracted extensive attention due to great application potentials in various fields. To realize a fundamental understanding of the intrinsic properties of GDY, the controllable synthesis of ultrathin and highly crystalline GDY is necessary and challenging. Herein, a confined interfacial synthetic strategy towards highly crystalline ultrathin GDY at the water/oil/organogel interface, with greatly improved control over GDY structures, is reported. The morphology and chemical composition of GDY was characterized accordingly. After loading with gold, the as-prepared hydrophobic Au/GDY system showed excellent performance in the nitrogen reduction reaction, reaching the highest yield of 4.15 μg cm⁻² h⁻¹ with a Faraday efficiency of 1.95 %.     

Reduction of CuO and Cu2O with H2: H embedding and kinetic effects in the formation of suboxides

Time-resolved X-ray diffraction, X-ray absorption fine structure, and first-principles density functional calculations were used to investigate the reaction of CuO and Cu(2)O with H(2) in detail. The mechanism for the reduction of CuO is complex, involving an induction period and the embedding of H into the bulk of the oxide. The in-situ experiments show that, under a normal supply of hydrogen, CuO reduces directly to metallic Cu without formation of an intermediate or suboxide (i.e., no Cu(4)O(3) or Cu(2)O). The reduction of CuO is easier than the reduction of Cu(2)O. The apparent activation energy for the reduction of CuO is about 14.5 kcal/mol, while the value is 27.4 kcal/mol for Cu(2)O. During the reduction of CuO, the system can reach metastable states (MS) and react with hydrogen instead of forming Cu(2)O. To see the formation of Cu(2)O, one has to limit the flow of hydrogen, slowing the rate of reduction to allow a MS --> Cu(2)O transformation. These results show the importance of kinetic effects for the formation of well-defined suboxides during a reduction process and the activation of oxide catalysts.     

CuO/Al2O3吸附SO2后氢再生及一体化回收硫磺

考察了添加Na助剂对CuO/Al2O3 的H2再生过程、硫磺产量及后续脱SO2过程活性的影响。结果表明,400℃再生温度下Na助剂添加后,CuO/Al2O3吸附剂的H2再生循环过程的硫磺产量及后续脱SO2过程硫容均变为添加前的1.3倍。Na助剂的添加明显增大吸附剂上载体Al2O3的硫化程度;且在Cu相和Na相共同存在情况下,吸附剂上生成的部分物质Al2(SO4)3在400℃以下即可被还原再生,从而明显提高了H2再生过程的硫磺产量和后续脱SO2硫容。     

Urea Assisted Synthesis of Flower Like CuO Nanostructures and Their Chemical Sensing Application for the Determination of Cadmium Ions

The novel nanostructures of CuO with improved morphology are strongly required for the development of devices with enhanced performance. In this study flower like nanostructures of CuO are synthesized by hydrothermal method using urea as tuning material for the morphology of CuO during the growth process. Scanning electron microscopy (SEM) and X‐ray diffraction (XRD) techniques were used for the characterization of these nanostructures. The nanostructures are highly dense, uniform and well aligned on the gold coated glass substrate. Moreover, CuO nanostructures exhibited pure phase of CuO. These novel CuO nanostructures were potentially used for the construction of cadmium ion sensor by functionalizing with tetrathia‐12‐crown‐4 a selective cadmium ion ionophore. The proposed cadmium ion sensor has detected the wide range of cadmium ion concentrations from 1.0×10^?9–1.0×10^?1 M with a sensitivity of 29.3±0.3 mV/decade and also a fast response time of less than 10.0 s is demonstrated. CuO nanostructures based cadmium ion selective electrode has also shown excellent reproducibility, repeatability, selectivity, and stability. The sensor electrode was also used as indicator electrode for the confirmation of practical utility and the obtained result describes the good behavior of the sensor in the potentiometric titration for the determination of cadmium ions.     

原位合成氧化镍硼/石墨炔杂化材料用于提高光/电催化产氢性能

当今世界面临严峻的能源紧缺和环境污染问题,发展高效无污染的清洁能源替代传统化石能源成为近几十年科研工作者的研究热点.其中,氢能由于具有高燃烧值和产物无污染等优点成为理想的替代能源.光/电催化水分解产生氢气是最有效的制氢方法之一.目前,高活性的产氢催化剂仍以贵金属为主,但贵金属价格高昂和稀缺性等限制了其大规模应用,因此,开发和设计廉价、高效的非贵金属产氢催化剂变得尤为重要.为了提高非贵金属催化剂的催化活性,基于非贵金属的复合材料的构建被广泛研究.例如,通过非贵金属和碳材料的复合,能够提高比表面积和电子传输速率,优化活性位点的电子结构,从而提高催化活性.石墨炔(GDY)作为一种新兴碳材料,由sp²-和sp-杂化碳共同组成.由于GDY具有高度π共轭结构,大的比表面积和独特的双炔键,可作为载体与非贵金属离子相互作用形成复合材料,制备高效产氢催化剂.基于此,本文在室温下原位合成了强耦合相互作用的氧化镍硼/石墨炔(NiBi/GDY)催化剂,并将其应用于光/电催化产氢反应.在光催化产氢反应中,采用曙红为光敏剂,三乙醇胺为牺牲剂,可见光下NiBi/GDY的光催化产氢速率可达4.54 mmol g^-1h^-1,产氢速率分别是氧化镍硼/石墨烯(NiBi/graphene)和NiBi的2.9倍和4.5倍.此外,NiBi/GDY在1.0 M KOH溶液中也表现出良好电催化产氢性能,电流密度为400 mA/cm²时其过电位为478.0 mV,低于商业铂碳(505.3 mV@400 mA/cm2).NiBi/GDY在光/电催化产氢实验中表现出的较好催化性能可归因于NiBi和GDY之间强耦合相互作用对NiBi电子结构的优化.上述研究结果表明,石墨炔可作为理想载体制备高效的光/电催化剂,同时本文为设计高效稳定的非贵金属产氢催化剂提供了一定的借鉴意义.     

Second Sphere Effects Promote Formic Acid Dehydrogenation by a Single-Atom Gold Catalyst Supported on Amino-Substituted Graphdiyne

Regulating the second sphere of homogeneous molecular catalysts is a common and effective method to boost their catalytic activities, while the second sphere effects have rarely been investigated for heterogeneous single-atom catalysts primarily due to the synthetic challenge for installing functional groups in their second spheres. Benefiting from the well-defined and readily tailorable structure of graphdiyne (GDY), an Au single-atom catalyst on amino-substituted GDY is constructed, where the amino group is located in the second sphere of the Au center. The Au atoms on amino-decorated GDY displayed superior activity for formic acid dehydrogenation compared with those on unfunctionalized GDY. The experimental studies, particularly the proton inventory studies, and theoretical calculations revealed that the amino groups adjacent to an Au atom could serve as proton relays and thus facilitate the protonation of an intermediate Au−H to generate H₂. Our study paves the way to precisely constructing the functional second sphere on single-atom catalysts.     

Selective Synthesis of 2D Mesoporous CuO Agglomerates by Pulsed Spark Discharge in Water

Metal oxide nanomaterials, including copper oxide, have attracted great attention due to their unique physical and chemical properties that are dependent on particle size and morphology. In this study, we propose an alternative technique for the synthesis of 2D mesoporous CuO agglomerates that is both efficient and ecological. This technique is based on the use of pulsed spark discharges between copper electrodes immersed in deionized water. Detailed TEM analyses show that the synthesized CuO nanostructures are composed of elementary nanocrystals with sizes in the order of a few nanometers. Assessments of the effects of applied voltage (5 and 20 kV) and discharge pulse width (100 and 500 ns) demonstrate that the latter parameter influences the size and density of nanocrystals in a nanostructure. Moreover, voltage and pulse width may both be used to finely control the direct optical band gap energy of CuO nanostructures between 3.0 and 3.4 eV. The efficient and ecological technique developed in this study produces 2D mesoporous CuO agglomerates that can be readily used in other processes.

     

Copper oxide nanostructures: Controlled synthesis and their catalytic performance

Oval-plate-like, sphere-like, bundle-like and plate-like copper oxide (CuO) nanostructures were prepared by hydrothermal method using Cu(CH₃COO)₂·H₂O and NaOH as the reagents in the absence of any surfactants or templates. The morphology and structure of CuO nanostructures could be easily tailored by adjusting the amount of NaOH. The catalytic activity of the as-prepared CuO nanostructures was demonstrated by catalytic oxidation of methylene blue (MB) in presence of hydrogen peroxide (H₂O₂). The oval-plate-like CuO exhibited better catalytic activity and which was mainly attributed to the larger specific surface area.     

Self-assembled Synthesis of 3D CuO Flocculus-like Nanosheet-based Hierarchical Nanostructures

A simple, surfactant-free, and environmentally benign method has been developed to synthesize a novel 3D flocculus-like CuO hierarchical nanostructure self-assembled with 2D nanosheet as building blocks. Detailed proofs demonstrate that the overall synthetic process underwent the dehydration and re-crystallization of precursor Cu(OH)₂ nanowires, and the subsequent two-step oriented attachment. In addition, 3D butterfly-like and flower-like CuO nanostructures consisted of 2D nanosheets could be obtained by adjusting the concentration of NaOH(c_NaOH) in the solution. c_NaOH played a key role in tailoring the thickness of the nanosheets and changing the morphology of the product. This report may be helpful to constructing fine-tune hierarchical CuO nanostructures under basic conditions.