共查询到20条相似文献,搜索用时 31 毫秒
1.
James Guo Sheng Moo Dr. Adriano Ambrosi Dr. Alessandra Bonanni Prof. Martin Pumera 《化学:亚洲杂志》2012,7(4):759-770
Graphene research is currently at the frontier of electrochemistry. Many different graphene‐based materials are employed by electrochemists as electrodes in sensing and in energy‐storage devices. Because the methods for their preparation are inherently different, graphene materials are expected to exhibit different electrochemical behaviors depending on the functionalities and density of defects present. Electrochemical treatment of these “chemically modified graphenes” (CMGs) represents an easy approach to alter surface functionalities and consequently tune the electrochemical performance. Herein, we report a preliminary electrochemical characterization of four common chemically modified graphenes, namely: graphene oxide, graphite oxide, chemically reduced graphene oxide, and thermally reduced graphene oxide. These CMGs were compared with graphite as a reference material. Cyclic voltammetry was used to ascertain the chemical functionalities present and to understand the potential ranges in which the materials were electroactive. Electrochemical treatment with either an oxidative or a reductive fixed potential were then carried out to activate these chemically modified graphenes. The effects of such electrochemical treatments on their electrocatalytic properties were then investigated by cyclic voltammetry in the presence of well‐known redox probes, such as [Fe(CN)6]4?/3?, Fe3+/2+, [Ru(NH3)6]2+/3+, and ascorbic acid. Thermally reduced graphene oxide exhibited the best electrochemical behavior amongst all of the CMGs, with the fastest rate of heterogeneous electron transfer (HET) and the lowest overpotentials. These findings will have far‐reaching consequences for the evaluation of different CMGs as electrode materials in electrochemical devices. 相似文献
2.
Hwee Ling Poh Prof. Zdeněk Sofer Michal Nováček Prof. Martin Pumera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(15):4284-4291
Doped graphene materials are of huge importance because doping with electron‐donating or electron‐withdrawing groups can significantly change the electronic structure and impact the electronic and electrochemical properties of these materials. It is highly important to be able to produce these materials in large quantities for practical applications. The only method capable of large‐scale production is the oxidative treatment of graphite to graphene oxide, followed by its consequent reduction. We describe a scalable method for a one‐step doping of graphene with phosphorus, with a simultaneous reduction of graphene oxide. Such a method is able to introduce significant amount of dopant (3.65 at. %). Phosphorus‐doped graphene is characterized in detail and shows important electronic and electrochemical properties. The electrical conductivity of phosphorus‐doped graphene is much higher than that of undoped graphene, owing to a large concentration of free carriers. Such a graphene material is expected to find useful applications in electronic, energy storage, and sensing devices. 相似文献
3.
Designed nitrogen and sulfur co‐doped graphene wrapped magnetic core‐shell supported Pd nanoparticles were synthesized through the following steps. Firstly, Fe3O4 was prepared, coated with silica and then functionalized with amine groups to create a positive charge on the structure for enhancing the interaction of the Fe3O4@SiO2 with graphene oxide. Secondary, the pre‐catalyst wrapped with graphene to enhance adsorption of aromatic substrates through π–π stacking. Thirdly, graphene was doped with nitrogen and sulfur to increase the grafting of Pd in hybrid. Finally, Pd NPs were attached on the surface of pre‐engineered structure to produce Fe3O4@SiO2@N,S‐wG@Pd which exhibited high performance in Suzuki reactions. This superior activity can be indexed to the incorporation of N and S atoms into graphene led to high anchoring and well‐dispersion of Pd NPs on the nanocomposite surface offering large amounts of active centers, that strongly increased the interaction between Pd and substrates to decreases Pd leaching. 相似文献
4.
Electrochemically Exfoliated Graphene and Graphene Oxide for Energy Storage and Electrochemistry Applications
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Dr. Adriano Ambrosi Prof. Martin Pumera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(1):153-159
Top‐down methods are of key importance for large‐scale graphene and graphene oxide preparation. Electrochemical exfoliation of graphite has lately gained much interest because of the simplicity of execution, the short process time, and the good quality of graphene that can be obtained. Here, we test three different electrolytes, that is, H2SO4, Na2SO4, and LiClO4, with a common exfoliation procedure to evaluate the difference in structural and chemical properties that result for the graphene. The properties are analyzed by means of scanning transmission electron microscopy (STEM), Raman spectroscopy, and X‐ray photoelectron spectroscopy. We then tested the graphene materials for electrochemical applications, measuring the heterogeneous electron transfer (HET) rates with a Fe(CN)63?/4? redox probe, and their capacitive behavior in alkaline solutions. We correlate the electrochemical features with the presence of structural defects and oxygen functionalities on the graphene materials. In particular, the use of LiClO4 during the electrochemical exfoliation of graphite allowed the formation of highly oxidized graphene with a C/O ratio close to 4.0 and represents a possible avenue for the mass production of graphene oxide as valid alternative to the current laborious and dangerous chemical procedures, which also have limited scalability. 相似文献
5.
Heteroatom‐doped carbon materials have been widely used in energy storage and conversion such as supercapacitors and electrocatalysts. In this work, L‐asparagine (Asn), an amino acid derivative, has been used as a doping agent to prepare nitrogen‐ doped reduced graphene oxide gels (N‐GAs). The 3D interconnected structure gives rise to the superior electrochemical properties for supercapacitor and electrocatalytic oxygen reduction reaction (ORR). The N‐GA‐4 (the mass ratio of Asn to graphene oxide (GO) is 4 : 1 by hydrothermal method) electrode shows the capacitance of 291.6 F·g–1 at 0.5 A·g–1. Meanwhile, the assembled symmetric supercapacitor achieves a maximum energy density of 23.8 Wh· kg–1 when the power density is 451.2 W·kg–1, and demonstrates an ultralong cycling life that the retention of capacitance is 99.3% after 80000 cycles. What's more, the annealed aerogel N‐GA‐4‐900 exhibits an onset potential (Eonset) of 0.95 V, half wave potential (E1/2) of 0.84 V (vs. RHE) and the oxygen reduction current density of 5.5 mA·cm–2 at 0.1 V with nearly four‐electron transfer, which are superior to commercial Pt/C. This work offers a new insight into the synthesis and applications of N‐GAs materials towards high performance in supercapacitors and ORR. 相似文献
6.
High Catalytic Activity of Nitrogen and Sulfur Co‐Doped Nanoporous Graphene in the Hydrogen Evolution Reaction
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Dr. Yoshikazu Ito Weitao Cong Dr. Takeshi Fujita Prof. Zheng Tang Prof. Mingwei Chen 《Angewandte Chemie (International ed. in English)》2015,54(7):2131-2136
Chemical doping has been demonstrated to be an effective way to realize new functions of graphene as metal‐free catalyst in energy‐related electrochemical reactions. Although efficient catalysis for the oxygen reduction reaction (ORR) has been achieved with doped graphene, its performance in the hydrogen evolution reaction (HER) is rather poor. In this study we report that nitrogen and sulfur co‐doping leads to high catalytic activity of nanoporous graphene in HER at low operating potential, comparable to the best Pt‐free HER catalyst, 2D MoS2. The interplay between the chemical dopants and geometric lattice defects of the nanoporous graphene plays the fundamental role in the superior HER catalysis. 相似文献
7.
Yuxin Liu Prof. Ping Liu Prof. Dongqing Wu Yanshan Huang Yanping Tang Prof. Yuezeng Su Prof. Fan Zhang Prof. Xinliang Feng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5617-5622
Heteroatom doping is an effective method to adjust the electrochemical behavior of carbonaceous materials. In this work, boron‐doped, carbon‐coated SnO2/graphene hybrids (BCTGs) were fabricated by hydrothermal carbonization of sucrose in the presence of SnO2/graphene nanosheets and phenylboronic acid or boric acid as dopant source and subsequent thermal treatment. Owing to their unique 2D core–shell architecture and B‐doped carbon shells, BCTGs have enhanced conductivity and extra active sites for lithium storage. With phenylboronic acid as B source, the resulting hybrid shows outstanding electrochemical performance as the anode in lithium‐ion batteries with a highly stable capacity of 1165 mA h g?1 at 0.1 A g?1 after 360 cycles and an excellent rate capability of 600 mA h g?1 at 3.2 A g?1, and thus outperforms most of the previously reported SnO2‐based anode materials. 相似文献
8.
Feng Zou Prof. Xianluo Hu Dr. Yongming Sun Dr. Wei Luo Fangfang Xia Long Qie Yan Jiang Prof. Yunhui Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(19):6027-6033
Zn2GeO4/N‐doped graphene nanocomposites have been synthesized through a fast microwave‐assisted route on a large scale. The resulting nanohybrids are comprised of Zn2GeO4 nanorods that are well‐embedded in N‐doped graphene sheets by in situ reducing and doping. Importantly, the N‐doped graphene sheets serve as elastic networks to disperse and electrically wire together the Zn2GeO4 nanorods, thereby effectively relieving the volume‐expansion/contraction and aggregation of the nanoparticles during charge and discharge processes. We demonstrate that an electrode that is made of the as‐formed Zn2GeO4/N‐doped graphene nanocomposite exhibits high capacity (1463 mAh g?1 at a current density of 100 mA g?1), good cyclability, and excellent rate capability (531 mAh g?1 at a current density of 3200 mA g?1). Its superior lithium‐storage performance could be related to a synergistic effect of the unique nanostructured hybrid, in which the Zn2GeO4 nanorods are well‐stabilized by the high electronic conduction and flexibility of N‐doped graphene sheets. This work offers an effective strategy for the fabrication of functionalized ternary‐oxide‐based composites as high‐performance electrode materials that involve structural conversion and transformation. 相似文献
9.
Germanium Quantum Dots Embedded in N‐Doping Graphene Matrix with Sponge‐Like Architecture for Enhanced Performance in Lithium‐Ion Batteries
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Jinwen Qin Xia Wang Prof. Dr. Minhua Cao Changwen Hu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(31):9675-9682
Germanium quantum dots embedded in a nitrogen‐doped graphene matrix with a sponge‐like architecture (Ge/GN sponge) are prepared through a simple and scalable synthetic method, involving freeze drying to obtain the Ge(OH)4/graphene oxide (GO) precursor and subsequent heat reduction treatment. Upon application as an anode for the lithium‐ion battery (LIB), the Ge/GN sponge exhibits a high discharge capacity compared with previously reported N‐doped graphene. The electrode with the as‐synthesized Ge/GN sponge can deliver a capacity of 1258 mAh g?1 even after 50 charge/discharge cycles. This improved electrochemical performance can be attributed to the pore memory effect and highly conductive N‐doping GN matrix from the unique sponge‐like structure. 相似文献
10.
Hwee Ling Poh Prof. Zdeněk Sofer Petr Šimek Dr. Ivo Tomandl Prof. Martin Pumera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8130-8136
Covalently functionalized graphene materials with well‐defined stoichiometric composition are of a very high importance in the research of 2D carbon material family due to their well‐defined properties. Unfortunately, most of the contemporary graphene‐functionalized materials do not have this kind of defined composition and, usually, the amount of heteroatoms bonded to graphene framework is in the range of 1–10 at. %. Herein, we show that by a well‐established hydroboration reaction chain, which introduces ?BH2 groups into the graphene oxide structure, followed by H2O2 or CF3COOH treatment as source of ?OH or ?H, we can obtain highly hydroxylated compounds of precisely defined composition with a general formula (C1O0.78H0.75)n, which we named graphol and highly hydroxylated graphane (C1(OH)0.51H0.14)n, respectively. These highly functionalized materials with an accurately defined composition are highly important for the field of graphene derivatives. The enhanced electrochemical performance towards important biomarkers as well as hydrogen evolution reaction is demonstrated. 相似文献
11.
Yongguang Liu Yingqiao Jiang Yanrong Lv Zhangxing He Lei Dai Ling Wang 《Molecules (Basel, Switzerland)》2021,26(16)
In spite of their low cost, high activity, and diversity, metal oxide catalysts have not been widely applied in vanadium redox reactions due to their poor conductivity and low surface area. Herein, SnO2/reduced graphene oxide (SnO2/rGO) composite was prepared by a sol–gel method followed by high-temperature carbonization. SnO2/rGO shows better electrochemical catalysis for both redox reactions of VO2+/VO2+ and V2+/V3+ couples as compared to SnO2 and graphene oxide. This is attributed to the fact that reduced graphene oxide is employed as carbon support featuring excellent conductivity and a large surface area, which offers fast electron transfer and a large reaction place towards vanadium redox reaction. Moreover, SnO2 has excellent electrochemical activity and wettability, which also boost the electrochemical kinetics of redox reaction. In brief, the electrochemical properties for vanadium redox reactions are boosted in terms of diffusion, charge transfer, and electron transport processes systematically. Next, SnO2/rGO can increase the energy storage performance of cells, including higher discharge electrolyte utilization and lower electrochemical polarization. At 150 mA cm−2, the energy efficiency of a modified cell is 69.8%, which is increased by 5.7% compared with a pristine one. This work provides a promising method to develop composite catalysts of carbon materials and metal oxide for vanadium redox reactions. 相似文献
12.
Self‐Assembling Synthesis of Free‐standing Nanoporous Graphene–Transition‐Metal Oxide Flexible Electrodes for High‐Performance Lithium‐Ion Batteries and Supercapacitors
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The synthesis of nanoporous graphene by a convenient carbon nanofiber assisted self‐assembly approach is reported. Porous structures with large pore volumes, high surface areas, and well‐controlled pore sizes were achieved by employing spherical silica as hard templates with different diameters. Through a general wet‐immersion method, transition‐metal oxide (Fe3O4, Co3O4, NiO) nanocrystals can be easily loaded into nanoporous graphene papers to form three‐dimensional flexible nanoarchitectures. When directly applied as electrodes in lithium‐ion batteries and supercapacitors, the materials exhibited superior electrochemical performances, including an ultra‐high specific capacity, an extended long cycle life, and a high rate capability. In particular, nanoporous Fe3O4–graphene composites can deliver a reversible specific capacity of 1427.5 mAh g?1 at a high current density of 1000 mA g?1 as anode materials in lithium‐ion batteries. Furthermore, nanoporous Co3O4–graphene composites achieved a high supercapacitance of 424.2 F g?1. This work demonstrated that the as‐developed freestanding nanoporous graphene papers could have significant potential for energy storage and conversion applications. 相似文献
13.
Sheng Chen Jingjing Duan Dr. Yonghong Tang Prof. Shi Zhang Qiao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(22):7118-7124
Graphene‐based hydrogels can be used as supercapacitor electrodes because of their excellent conductivity, their large surface area and their high compatibility with electrolytes. Nevertheless, the large aspect ratio of graphene sheets limits the kinetics of processes occurring in the electrode of supercapacitors. In this study, we have introduced in‐plane and out‐of‐plane pores into a graphene–nickel hydroxide (Ni(OH)2) hybrid hydrogel, which facilitates charge and ion transport in the electrode. Due to its optimised chemistry and architecture, the hybrid electrode demonstrates excellent electrochemical properties with a combination of high charge storage capacitance, fast rate capability and stable cycling performance. Remarkably, the Ni(OH)2 in the hybrid contributes a capacitance as high as 3138.5 F g?1, which is comparable to its theoretical capacitance, suggesting that such structure facilitates effectively charge‐transfer reactions in electrodes. This work provides a facile pathway for tailoring the porosity of graphene‐based materials for improved performances. Moreover, this work has also furthered our understanding in the effect of pore and hydrogel structures on the electrochemical properties of materials. 相似文献
14.
Synergistic Ternary Composite (Carbon/Fe3O4@Graphene) with Hollow Microspherical and Robust Structure for Li‐Ion Storage
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Xingxing Li Xueying Zheng Prof. Jie Shao Tian Gao Qiang Shi Prof. Dr. Qunting Qu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(1):376-381
The electrode materials with hollow structure and/or graphene coating are expected to exhibit outstanding electrochemical performances in energy‐storage systems. 2D graphene‐wrapped hollow C/Fe3O4 microspheres are rationally designed and fabricated by a novel facile and scalable strategy. The core@double‐shell structure SPS@FeOOH@GO (SPS: sulfonated polystyrene, GO: graphene oxide) microspheres are first prepared through a simple one‐pot approach and then transformed into C/Fe3O4@G (G: graphene) after calcination at 500 °C in Ar. During calcination, the Kirkendall effect resulting from the diffusion/reaction of SPS‐derived carbon and FeOOH leads to the formation of hollow structure carbon with Fe3O4 nanoparticles embedded in it. In the rationally constructed architecture of C/Fe3O4@G, the strongly coupled C/Fe3O4 hollow microspheres are further anchored onto 2D graphene networks, achieving a strong synergetic effect between carbon, Fe3O4, and graphene. As an anode material of Li‐ion batteries (LIBs), C/Fe3O4@G manifests a high reversible capacity, excellent rate behavior, and outstanding long‐term cycling performance (1208 mAh g?1 after 200 cycles at 100 mA g?1). 相似文献
15.
Coated/Sandwiched rGO/CoSx Composites Derived from Metal–Organic Frameworks/GO as Advanced Anode Materials for Lithium‐Ion Batteries
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Dr. Dongming Yin Dr. Gang Huang Dr. Feifei Zhang Dr. Yuling Qin Dr. Zhaolin Na Prof. Yaoming Wu Prof. Limin Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1467-1474
Rational composite materials made from transition metal sulfides and reduced graphene oxide (rGO) are highly desirable for designing high‐performance lithium‐ion batteries (LIBs). Here, rGO‐coated or sandwiched CoSx composites are fabricated through facile thermal sulfurization of metal–organic framework/GO precursors. By scrupulously changing the proportion of Co2+ and organic ligands and the solvent of the reaction system, we can tune the forms of GO as either a coating or a supporting layer. Upon testing as anode materials for LIBs, the as‐prepared CoSx‐rGO‐CoSx and rGO@CoSx composites demonstrate brilliant electrochemical performances such as high initial specific capacities of 1248 and 1320 mA h g?1, respectively, at a current density of 100 mA g?1, and stable cycling abilities of 670 and 613 mA h g?1, respectively, after 100 charge/discharge cycles, as well as superior rate capabilities. The excellent electrical conductivity and porous structure of the CoSx/rGO composites can promote Li+ transfer and mitigate internal stress during the charge/discharge process, thus significantly improving the electrochemical performance of electrode materials. 相似文献
16.
Gi‐Hyeok Lee Jinpeng Wu Duho Kim Kyeongjae Cho Maenghyo Cho Wanli Yang Yong‐Mook Kang 《Angewandte Chemie (International ed. in English)》2020,59(22):8681-8688
Redox reactions of oxygen have been considered critical in controlling the electrochemical properties of lithium‐excessive layered‐oxide electrodes. However, conventional electrode materials without overlithiation remain the most practical. Typically, cationic redox reactions are believed to dominate the electrochemical processes in conventional electrodes. Herein, we show unambiguous evidence of reversible anionic redox reactions in LiNi1/3Co1/3Mn1/3O2. The typical involvement of oxygen through hybridization with transition metals is discussed, as well as the intrinsic oxygen redox process at high potentials, which is 75 % reversible during initial cycling and 63 % retained after 10 cycles. Our results clarify the reaction mechanism at high potentials in conventional layered electrodes involving both cationic and anionic reactions and indicate the potential of utilizing reversible oxygen redox reactions in conventional layered oxides for high‐capacity lithium‐ion batteries. 相似文献
17.
Synthesis of Phosphorus‐Doped Graphene and its Wide Potential Window in Aqueous Supercapacitors
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Yangyang Wen Dr. Bei Wang Congcong Huang Prof. Lianzhou Wang Dr. Denisa Hulicova‐Jurcakova 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):80-85
Phosphorus‐doped (P‐doped) graphene with the P doping level of 1.30 at % was synthesized by annealing the mixture of graphene and phosphoric acid. The presence of P was confirmed by elemental mapping and X‐ray photoelectron spectroscopy, while the morphology of P‐doped graphene was revealed by using scanning electron microscopy and transmission electron microscopy. To investigate the effect of P doping, the electrochemical properties of P‐doped graphene were tested as a supercapacitor electrode in an aqueous electrolyte of 1 M H2SO4. The results showed that doping of P in graphene exhibited significant improvement in terms of specific capacitance and cycling stability, compared with undoped graphene electrode. More interestingly, the P‐doped graphene electrode can survive at a wide voltage window of 1.7 V with only 3 % performance degradation after 5000 cycles at a current density of 5 A g?1, providing a high energy density of 11.64 Wh kg?1 and a high power density of 831 W kg?1. 相似文献
18.
Sun‐Min Jung Eun Kwang Lee Min Choi Dongbin Shin In‐Yup Jeon Jeong‐Min Seo Prof. Hu Young Jeong Prof. Noejung Park Prof. Joon Hak Oh Prof. Jong‐Beom Baek 《Angewandte Chemie (International ed. in English)》2014,53(9):2398-2401
Heteroatom‐doping into graphitic networks has been utilized for opening the band gap of graphene. However, boron‐doping into the graphitic framework is extremely limited, whereas nitrogen‐doping is relatively feasible. Herein, boron/nitrogen co‐doped graphene (BCN‐graphene) is directly synthesized from the reaction of CCl4, BBr3, and N2 in the presence of potassium. The resultant BCN‐graphene has boron and nitrogen contents of 2.38 and 2.66 atom %, respectively, and displays good dispersion stability in N‐methyl‐2‐pyrrolidone, allowing for solution casting fabrication of a field‐effect transistor. The device displays an on/off ratio of 10.7 with an optical band gap of 3.3 eV. Considering the scalability of the production method and the benefits of solution processability, BCN‐graphene has high potential for many practical applications. 相似文献
19.
Synthesis and characterization of graphene oxide‐based hybrid ligand and its metal complexes: Highly efficient sensor and catalytic properties
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A new graphene oxide‐based hybrid material (HL) and its Co(II), Cu(II) and Ni(II) metal complexes were prepared. Firstly, graphene oxide and (3‐aminopropyl)trimethoxysilane were reacted to give graphene oxide–3‐(aminopropyl)trimethoxysilane (GO‐APTMS) hybrid material. After that, hybrid material HL was synthesized from the reaction of GO‐APTMS and 2,6‐diformyl‐4‐methylphenol. Finally, Co(II), Cu(II) and Ni(II) complexes of HL were obtained. All the materials were characterized using various techniques. The chemosensor properties of HL were investigated against Na+, K+, Cd2+, Co2+, Cu2+, Hg2+, Ni2+, Zn2+, Al3+, Cr3+, Fe3+ and Mn3+ ions and it was found that HL has selective chemosensing to Fe3+ ion. All the graphene oxide‐supported complexes were used as heterogeneous catalysts in the oxidation of 2‐methylnaphthalene (2MN) to 2‐methyl‐1,4‐naphthoquinone (vitamin K3, menadione) in the presence of hydrogen peroxide, acetic acid and sulfuric acid. The Cu(II) complex showed good catalytic properties compared to the literature. The selectivity of 2MN to vitamin K3 was 60.23% with 99.75% conversion using the Cu(II) complex. 相似文献
20.
Maximizing the Catalytic Activity of Nanoparticles through Monolayer Assembly on Nitrogen‐Doped Graphene
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Dr. Chao Yu Xuefeng Guo Mengqi Shen Bo Shen Michelle Muzzio Zhouyang Yin Prof. Qing Li Zheng Xi Junrui Li Prof. Christopher T. Seto Prof. Shouheng Sun 《Angewandte Chemie (International ed. in English)》2018,57(2):451-455
We report a facile method for assembly of a monolayer array of nitrogen‐doped graphene (NG) and nanoparticles (NPs) and the subsequent transfer of two layers onto a solid substrate (S). Using 3 nm NiPd NPs as an example, we demonstrate that NiPd‐NG‐Si (Si=silicon wafer) can function as a catalyst and show maximum NiPd catalysis for the hydrolysis of ammonia borane (H3NBH3, AB) with a turnover frequency (TOF) of 4896.8 h?1 and an activation energy (Ea) of 18.8 kJ mol?1. The NiPd‐NG‐S catalyst is also highly active for catalyzing the transfer hydrogenation from AB to nitro compounds, leading to the green synthesis of quinazolines in water. Our assembly method can be extended to other graphene and NP catalyst materials, providing a new 2D NP catalyst platform for catalyzing multiple reactions in one pot with maximum efficiency. 相似文献