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Using simple methods to obtain efficient catalysts has been a long-standing goal for researchers. In this work, the employment of a one-pot pyrolysis reaction to achieve molecular confinement, has led to the preparation of ruthenium (Ru)-based nanoclusters in a carbon matrix. A unique feature of the synthetic approach employed is that solvent and substrates were calcined together. As solvent evaporates, during calcination, the substrates form a dense solid which has the effect of limiting the aggregation of Ru centers during the carbonization process. The catalyst prepared in this simple manner showed an impressively high activity with respect to the hydrogen/oxygen evolution reaction (HER/OER). The Ru nanoclusters (Ru NCs), as the hydrogen evolution reaction (HER) catalysts, require ultralow overpotentials of 5 mV and 5.1 mV at −10 mA·cm−2 in 1.0 M KOH, and 0.5 M H2SO4, respectively. Furthermore, the catalyst prepared by the one-pot method has higher crystallinity, a higher Ru content and an ultrafine cluster size, which contributes to its exceptional electrochemical performance. Meanwhile, the RuOX nanoclusters (RuOX NCs), obtained by oxidizing the aforementioned Ru NCs, exhibited good oxygen evolution reaction (OER) performance with an overpotential of 266 mV at 10 mA·cm−2. When applied to overall water splitting, Ru/RuOX nanoclusters as the cathode and anode catalysts can reach 10 mA·cm−2 at cell voltages of only 1.49 V in 1 M KOH.

Controlling the morphology of highly homogeneous nanoribbons is one of the main goals for synthesizing catalysts with excellent activity and durability. In this Communication, platinum (Pt) nanoribbons were synthesized by a one-pot method. We used ammonium fluoride (NH4F) as the regulator, under 8 atm of hydrogen (H2), to synthesize zigzag-shaped two-dimensional Pt nanoribbons. Benefiting from their unique morphology, the Pt nanoribbons display superior electrocatalytic activity and stability.

The porous polymer matrix with good stability and confined microenvironment is considered as ideal support to stabilize isolated metal centers for catalysis. Herein, we report a "one-pot" method to prepare a kind of palladium complexed with azo porous organic polymer nanospheres (Pd-azo-POPs). The method combines the synthesis of Azo-POPs with the reduction of the Pd ion, where azo is conducted as an anchoring group to limit the growth of Pd. The unique structure is conductive to the formation of a uniform active center and providing better electron transfer. Pd-azo-POPs-80 exhibits high catalytic activity and recycle stability both in 4-nitrophenol reduction and Suzuki-Miyaura coupling. The k nor for the 4-nitrophenol reduction was 174.7 min -1 mM -1 and remains the conversion above 90% after 6 cycles. Meanwhile, the yield was still up to 94.5% after 5 cycles for the Suzuki-Miyaura coupling reaction of benzene derivatives with I/Br under milder conditions.

Transition metal selenides have attracted enormous research attention as anodes for lithium-ion batteries (LIBs) due to their high theoretical specific capacities. Nevertheless, the low electronic conductivity and dramatic volume variation in electrochemical reaction processes result in rapid capacity fading and poor rate capability. Herein, a metal–organic framework is used as a template to in situ synthesize Sb2Se3 nanoparticles encapsulated in N-doped carbon nanotubes (N-CNTs) grafted on reduced graphene oxide (rGO) nanosheets. The synergistic effects of N-doped carbon nanotubes and reduced graphene oxide nanosheets are beneficial for providing good electrical conductivity and maintaining the structural stability of electrode materials, leading to stable cycling performance and superior rate performance. Kinetic analysis suggests that the electrochemical reaction kinetics is dominated by pseudocapacitive contribution. Notably, a high discharge capacity of 451.1 mA h g−1 at a current density of 2.0 A g−1 is delivered after 450 cycles. Even at a high current density of 10.0 A g−1, a discharge capacity of 192.6 mA h g−1 is maintained after 10 000 cycles. When coupled with a commercial LiFePO4 cathode, the full batteries show an excellent discharge specific capacity of 534.5 mA h g−1 at 0.2 A g−1. This work provides an effective strategy for constructing high-performance anodes for Li+ storage.

Developing the highly efficient and low-cost electrocatalysts for the oxygen evolution reactions (OERs), as vital half reactions of water splitting, is crucial for renewable energy technology. The electrocatalysts based on multi-component and hierarchically structured non-noble metal hydr(oxy)oxide materials are of great prospects. Herein, we report an efficient strategy at low temperatures for synthesizing amorphous iron-doped cobalt-molybdenum ultrathin hydroxide (Fe-CoMo UH) nanosheets. Benefiting from the ultrathin amorphous structure and multi-metal coordination, Fe-CoMo UH nanosheets exhibit outstanding performance for OERs with a low overpotential of 245 mV at 10 mA cm−2, a small Tafel slope of 37 mV dec−1 and an excellent stability for 90 h. The mass activity of Fe-CoMo UH is higher than that of commercial Ir/C and most of the transition metal hydroxide catalysts. This work provides a feasible consideration for the construction of promising efficient non-noble metal catalysts.

Over the past decades, metal selenides have drawn considerable attention due to their high theoretical specific capacity. However, huge volume changes and sluggish electrochemical transfer kinetics hinder their applications in energy storage and conversion. In this work, we demonstrate an efficient and ingenious synthesis strategy to regulate nickel selenide electrodes by the introduction of copper and in situ coating with carbon (Cu-NiSe2@C). When used as anodes for lithium-ion batteries, the as-synthesized Cu-NiSe2@C delivered a high capacity of 1630 mA h g−1 at 1.0 A g−1 after 200 cycles and excellent rate performance as well as long-term cycling stability with a high capacity of 489 mA h g−1 at 10 A g−1 after 20 000 cycles. When coupled with a commercial LiFePO4 cathode, the full cells showed a high capacity of 463 mA h g−1 at 0.2 A g−1. Their superior electrochemical performance can be attributed to the synergistic effect of the in situ carbon coating and copper doping, which can promote the electron/ion transfer kinetics, as well as alleviate the volume expansion during cycling. This work will open new opportunities for the development of high-performance anodes for lithium storage.

Molybdenum selenide is a potential alternative to counter electrode of a platinum-free dye-sensitized solar cell (DSSC). In this work, an in situ magnetron sputtering method is developed to prepare MoSe2 electrodes. The MoSe2 electrodes obtained at various temperatures from 300 and 550 °C are used as counter electrode for a dye-sensitized solar cell. Photovoltaic measurement results indicate that the MoSe2 electrodes prepared at 400 °C has the optimized performance, and the corresponding DSSCs provide an energy conversion efficiency of 6.83% which is comparable than that of the reference DSSC with platinum as counter electrode (6.51%). With further increas-ing the preparation temperature of the MoSe2 electrodes, the corresponding DSSCs decrease gradu-ally to 5.96% for 550 °C. Electrochemical impedance spectra (EIS) reveal that charge transfer resis-tance (Rct) of MoSe2 electrodes is rising with increase of the temperature from 400 to 500 °C, sug-gesting a downward electrocatalytic activity. Though the MoSe2 electrode prepared at 550 °C show a reduced Rct, its series resistance (Rs) and diffusion resistance (Zw) increase obviously. Considering that MoSe2 phase cannot be formed at 300 °C, it can be concluded that the prepared temperature as low as possible is favored for its final electrochemical performance. The results are very significant for developing low-cost and responsible counter electrodes for dye-sensitized solar cells

The rational-design and synthesis of transition-metal compounds with outstanding electrochemical activity and durability for renewable energy systems have attracted tremendous research interest in recent years. Herein, we report a facile and unique strategy to synthesize N-doped carbon nanotube-encapsulated Ni nanoparticles on reduced graphene oxide (Ni@NC-rGO). The optimized nanostructure determines the synergetic effects among the Ni nanoparticles, N-doped CNTs and graphene nanosheets, thus resulting in extraordinary electrochemical performances. When applied as an anode for lithium-ion batteries (LIBs), the Ni@NC-rGO electrode displayed high reversible capacity, stable cycling performance and superior rate capability. Moreover, the resulting Ni@NC-rGO nanocomposites exhibited low overpotential and considerable durability for the hydrogen evolution reaction (HER). Our study may provide a feasible methodology for the preparation of high-performance nanostructured materials for practical energy storage and conversion applications.

Metal-organic frameworks (MOFs)-derived catalysts exhibit highly-efficient hydrogen or oxygen evolution performance on water splitting. However, it is an urgent problem to construct bifunctional electrocatalysts for both hydrogen and oxygen evolution performance. Herein, we adopted Ag nanowires as templates to prepare one-dimensional Ag nanowire@ZIF-8@ZIF-67 precursors (1D AgNW@ZIF-8@ZIF-67). Through pyrolysis, AgNW@ZIF-8@ZIF-67 precursors transformed into nitrogen-doped carbon frameworks (NCF) embedded with zinc-cobalt (ZnCo) nanoparticles on the surface of Ag NWs (denoted as Ag@ZnCo/NCF nanohybrids). The nanohybrids were consisted of Ag NWs with good conductivity and ZnCo/NCF nanohybrids with rich accessible active sites. Benefiting from their large specific surface area, accessible active sites and synergistic effect among components, Ag@ZnCo/NCF nanohybrids exhibit lower overpotentials of 139 mV and 279 mV at the current density of 10 mA cm−2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline solution, severally. Compared with other catalysts, Ag@ZnCo/NCF nanohybrids possess smaller Tafel slope, indicating their higher catalytic activity. This work provides a new perspective for designing low-cost and highly efficient bifunctional electrocatalysts for overall water splitting.

In this manuscript, we utilize a facile and efficient step-by-step strategy to synthesize three-layered C@TiO2@MoS2 hierarchical nanocomposites. These novel hybrids serve as anode materials in lithium-ion batteries (LIBs). The designed structure, in which MoS2 nanosheets are uniformly grown on TiO2 coated carbon hollow spheres, can enhance the electrical conductivity of electrodes, shorten the diffusion length of Li+ ions, alleviate the expansion of electrode materials and provide more active sites for lithium ion storage. As anode materials for lithium-ion batteries (LIBs), the C@TiO2@MoS2 hierarchical nanocomposites exhibit a high initial specific capacity (1687 mA h g-1) and good cycling performance (993.2 mA h g-1 after 100 cycles at a current density of 0.2 A g-1). Furthermore, the C@TiO2@MoS2 electrode exhibits high rate capacities of 963, 860, 806, 743, 703, 664 and 633 mA h g-1 at different current densities of 200, 500, 1000, 2000, 3000, 4000 and 5000 mA h g-1, respectively. The electrochemical performances stated above prove that the as-prepared C@TiO2@MoS2 nanocomposites can be promising anode materials for high-performance lithium-ion batteries.

Herein, we have developed a facile and effective approach for synthesizing a novel kind of porous nitrogen-doped carbon-coated MnO nanosphere. The porous Mn2O3 nanospheres are initially obtained by the calcination treatment of a coordination self-assembled aggregation precursor (referred to as Mn(OAc)2-C-8). Then, MnO@N-doped carbon composites (MnO@NCs) are obtained by the calcination of the Mn2O3 nanospheres coated with polydopamine (Mn2O3@PDA). The MnO@NCs are evaluated as an anode for lithium ion batteries (LIBs), which exhibit high specific capacity, stable cycling performance (1096.6 mA h g−1 after 100 cycles at 100 mA g−1) and high coulombic efficiency (about 99% over 100 cycles). The unique structure design and synergistic effect not only settle the challenges of low conductivity and poor cycling stability of transition metal oxides but also resolve the imperfection of inferior specific capacity of traditional graphite materials. Importantly, it may provide a commendable conception for developing new-fashioned anode materials to improve the lithium storage capability and electrochemical performance.

This Communication demonstrates a novel and facial approach to achieving monodispersed sea-urchin-like Pt nanodendrites under a 1 bar hydrogen environment at 165 °C. These Pt nanodendrites can be further used as seeds for the formation of Pt/Au nanodendrites. Both Pt and Pt/Au nanodendrites exhibit the desired eletrocatalytic activities for the methanol oxidation reaction.

Highlights Bimetallic oxides nanoparticles derived from metal–oleate complexes embedded in 3D graphene networks were fabricated by a facile and rational design approach. The unique porous architecture promotes charge transfer so as to enhance the reversible capacity. The synergetic effect between the 0D nanoparticles and 3D graphene networks plays an essential role in the superb electrochemical performance. Electronic supplementary material The online version of this article (10.1007/s40820-019-0247-3) contains supplementary material, which is available to authorized users., In this manuscript, we have demonstrated the delicate design and synthesis of bimetallic oxides nanoparticles derived from metal–oleate complex embedded in 3D graphene networks (MnO/CoMn2O4 ⊂ GN), as an anode material for lithium ion batteries. The novel synthesis of the MnO/CoMn2O4 ⊂ GN consists of thermal decomposition of metal–oleate complex containing cobalt and manganese metals and oleate ligand, forming bimetallic oxides nanoparticles, followed by a self-assembly route with reduced graphene oxides. The MnO/CoMn2O4 ⊂ GN composite, with a unique architecture of bimetallic oxides nanoparticles encapsulated in 3D graphene networks, rationally integrates several benefits including shortening the diffusion path of Li+ ions, improving electrical conductivity and mitigating volume variation during cycling. Studies show that the electrochemical reaction processes of MnO/CoMn2O4 ⊂ GN electrodes are dominated by the pseudocapacitive behavior, leading to fast Li+ charge/discharge reactions. As a result, the MnO/CoMn2O4 ⊂ GN manifests high initial specific capacity, stable cycling performance, and excellent rate capability. Electronic supplementary material The online version of this article (10.1007/s40820-019-0247-3) contains supplementary material, which is available to authorized users.

Developing stable, efficient and economical electrocatalytic materials is still challenging for hydrogen evolution reaction (HER). Hence, we develop a Pd/Ni bimetallic carbon electrocatalyst (Pd/Ni-NC) with outstanding electrocatalytic performance. The catalyst derived from Pd-doped Ni-MOF (Pd/Ni-MOF) has particles and needle-like carbon tubes on its surface and is similar in shape to setaria. Benefiting from the composition and the unique structure, Pd/Ni-NC shows excellent HER catalytic performance with 16 mV at 10 mA cm−2, superior to Pd or Ni single metal-carbon catalyst. Furthermore, it maintains stable catalytic activity under constant current for 25h. These results show the strategy that obtaining Pd and Ni bimetallic MOF by cation exchange and its corresponding bimetallic carbon material with setaria-shaped structure by calcination is powerful for high efficient HER performance.

Different from the conventional synthesis methods and substrates, we designed a brand new method for synthesizing amides with platinum nanowires as catalysts and tert -butylhydroperoxide (TBHP) as the oxidant. Influence of factors, such as the catalyst, solvents, and the reaction temperature, were studied to determine the optimal reaction conditions. In addition, we explored the substrate generality and observed excellent yields.

A novel type of transition bimetal–organic frameworks was described as a heterogeneous catalyst for the oxidative coupling of amines to imines under mild conditions, which was easily synthesized by the coordination assembly of manganese(II) and cobalt(II) with 1,3,5-benzenetricarboxylic acid (H3BTC) for the first time. The metal–organic framework material was characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetry and N2 sorption. As an environmentally benign heterogeneous catalyst, the catalytic ability of the metal–organic framework material was then detected to be excellent for the tert-butyl hydroperoxide (TBHP) promoted direct oxidative coupling of benzylamines to imines in excellent yields (up to 100%) in methanol for 3 h. More importantly, it could be recycled up to six runs, while still maintaining its high catalytic activity.

A novel kind of Co-based metal–organic frameworks (MOFs) are firstly prepared by coordination assembly of Co(II) and 1,3,5-benzenetricarboxylic acid (H3BTC) through a hydrothermal route (referred to as Co-BTC MOF). Such Co-BTC MOF have a zigzag vermicular-like shape with a length of 126 nm and a width of 55 nm. Co-BTC MOFs without calcination treatment are applied as anode materials for lithium-ion batteries (LIBs) and show superior electrochemical performance, including high lithium storage capacity (1739 mA h g−1 in the first discharge process at a current density of 100 mA g−1), excellent coulombic efficiency (above 99% in the 199th cycle) and cycling performance (>750 mA h g−1 over 200 cycles) in the potential range of 0.01–3.0 V vs. Li/Li+. Such excellent electrochemical performance may be derived from the conjugated carboxylate moiety and the linker structure. More importantly, the facile approach may also be extended to other metal-based MOFs and the intriguing results show that nano-sized MOFs will be regarded as futuristic anode materials for advanced lithium storage.

High step- and atom-economy are the endlessly pursued in organic and pharmaceutical syntheses. Herein, a new method for directly coupling benzyl/allyl alcohols with malonates via a palladium catalyzed Tsuji–Trost type reaction was developed. The reaction was carried out in an organic carbonate solvent which would activate alcohols in situ, replacing the traditional pre-synthesized carbonates. The new process demonstrated high efficiency, high selectivity and high generality. A wide variety of mono-substituted and bis-substituted malonates were selectively produced under different conditions, and this method represents a more step- and atom-economical and environmentally benign synthetic protocol.

Nanostructured hybrid metal sulfides have attracted intensive attention due to their fascinating properties that are unattainable by the single-phased counterpart. Herein, we report an efficient approach to construct cobalt sulfide/molybdenum disulfide (Co9 S8 /MoS2 ) wrapped with reduced graphene oxide (rGO). The unique structures constructed by ultrathin nanosheets and synergetic effects benefitting from bimetallic sulfides provide improved lithium ions reaction kinetics, and they retain good structural integrity. Interestingly, the conductive rGO can facilitate electron transfer, increase the electronic conductivity and accommodate the strain during cycling. When evaluated as anode materials for lithium-ion batteries (LIBs), the resultant reduced graphene oxide-coated cobalt sulfide/molybdenum disulfide (Co9 S8 /MoS2 @rGO) nanotubes deliver high specific capacities of 1140, 948, 897, 852, 820, 798 and 784 mAh g-1 at the various discharging current densities of 0.2, 0.5, 1, 2, 3, 4 and 5 A g-1 , respectively. In addition, they can maintain an excellent cycle stability with a discharge capacity of 807 mAh g-1 at 0.2 A g-1 after 70 cycles, 787 mAh g-1 at 1 A g-1 after 180 cycles and 541 mAh g-1 at 2 A g-1 after 200 cycles. The proposed method may offer fundamental understanding for the rational design of other hybrid functional composites with high Li-storage properties.

Herein, we reported a facile route to fabricate carbon and Au treated TiO 2 mesoporous hollow spheres (MHTiO 2 @C–Au) as high performance anode materials for lithium ion batteries. The high porosity of the hollow spheres, together with the inner carbon supporting and superficial Au coating, enhanced the cycling stability and rate performance of the MHTiO 2 @C–Au electrode significantly. The MHTiO 2 @C–Au composite exhibits a high reversible specific capacity of 186.6 mA h g −1 after 200 cycles at the current density of 1.0C, superior rate performances of around 151.0 mA h g −1 at the current rate of 5.0C. The outstanding electrochemical property is attributed to the overall structural features of the MHTiO 2 @C–Au, which can not only shorten the diffusion path of lithium ions and electrons, but also improve the stability of the hollow structures during the lithium ion insertion and extraction process.

Monodisperse Pt nanoparticles (NPs) were prepared by reduction of platinum acetylacetonate in octadecene with the presence of Fe(CO)5. The synthesized nanocatalysts presented high activity and selectively for hydrogenation of ortho-halogenated nitrobenzene to the corresponding ortho-halogenated aniline under mild reaction conditions.

We developed a simple and efficient method to synthesize aromatic azos by hydrogen transfer using palladium(II) acetylacetonate as a catalyst and isopropyl alcohol as a hydrogen source. Furthermore, this system also showed catalytic potential for the hydrogenation of carbonyl groups or C=C bonds with yields up to ∼97%.

High step- and atom-economy are the endlessly pursued in organic and pharmaceutical syntheses. Herein, a new method for directly coupling benzyl/allyl alcohols with malonates via a palladium catalyzed Tsuji–Trost type reaction was developed. The reaction was carried out in an organic carbonate solvent which would activate alcohols in situ, replacing the traditional pre-synthesized carbonates. The new process demonstrated high efficiency, high selectivity and high generality. A wide variety of mono-substituted and bis-substituted malonates were selectively produced under different conditions, and this method represents a more step- and atom-economical and environmentally benign synthetic protocol.

A novel type of transition bimetal–organic frameworks was described as a heterogeneous catalyst for the oxidative coupling of amines to imines under mild conditions, which was easily synthesized by the coordination assembly of manganese(II) and cobalt(II) with 1,3,5-benzenetricarboxylic acid (H3BTC) for the first time. The metal–organic framework material was characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetry and N2 sorption. As an environmentally benign heterogeneous catalyst, the catalytic ability of the metal–organic framework material was then detected to be excellent for the tert-butyl hydroperoxide (TBHP) promoted direct oxidative coupling of benzylamines to imines in excellent yields (up to 100%) in methanol for 3 h. More importantly, it could be recycled up to six runs, while still maintaining its high catalytic activity.

A series of N-substituted isoindolinones have been successfully synthesized through the reductive C-N coupling and intramolecular amidation of 2-carboxybenzaldehyde and amines. This one-pot synthesis gives excellent yields using ultrathin Pt nanowires as catalysts under 1 bar of hydrogen. These unsupported catalysts can also be used for the synthesis of phthalazinones in high yield when hydrazine or phenyl hydrazine is used instead of amines.

An efficient near-infrared (NIR) dowmconversion (DC) has been demonstrated in the CaMoO4:Yb3+ phosphors. Very strong NIR emission around 998 nm from the 2F(7/2) --> 2F(5/2) transition of the Yb3+ has been observed under ultraviolet excitation. A similar broad excitation band due to the absorption of the host CaMoO4 has been recorded when the NIR emission of Yb3+ and the visible molybdate (MoO4(-2)) emission are monitored, which suggests an efficient energy transfer (ET) from the host to the Yb3+. The Yb3+ concentration-dependent luminescence properties and lifetimes of both the visible and NIR emissions have also been studied. The lifetime of the molybdate emission decreases rapidly with the increasing Yb3+ concentration, further verifying the efficient ET from the host to the Yb3+. Moreover, the low temperature measurements have also been carried out to investigate the ET mechanism in the phosphors. A cooperative energy transfer (CET) mechanism has been proposed to rationalize the DC effect. The newly studied CaMoO4:Yb3+ DC phosphors, which can convert the broadband emission of the MoO4(2-) into NIR emission of Yb3+ with a twofold increase in the photon number will have potential application in greatly enhancing the response of silicon-based solar cells with a relatively higher Yb3+ quenching concentration.

In this manuscript, we synthesize a porous three-dimensional anode material consisting of molybdenum dioxide nanodots anchored on nitrogen (N)/sulfur (S) co-doped reduced graphene oxide (GO) (3D MoO2/NP-NSG) through hydrothermal, lyophilization and thermal treatment. First, the NP-NSG is formed via hydrothermal treatment using graphene oxide, hydrogen peroxide (H2O2), and thiourea as the co-dopant for N and S, followed by calcination of the N/S co-doped GO in the presence of ammonium molybdate tetrahydrate to obtain the 3D MoO2/NP-NSG product. This novel material exhibits a series of out-bound electrochemical performances, such as superior conductivity, high specific capacity, and excellent stability. As an anode for lithium-ion batteries (LIBs), the MoO2/NP-NSG electrode has a high initial specific capacity (1376 mAh g-1), good cycling performance (1250 mAh g-1 after 100 cycles at a current density of 0.2 A g-1), and outstanding Coulombic efficiency (99% after 450 cycles at a current density of 1 A g-1). Remarkably, the MoO2/NP-NSG battery exhibits exceedingly good rate capacities of 1021, 965, 891, 760, 649, 500 and 425 mAh g-1 at different current densities of 200, 500, 1000, 2000, 3000, 4000 and 5000 mA g-1, respectively. The superb electrochemical performance is owed to the high porosity of the 3D architecture, the synergistic effect contribution from N and S co-doped in the reduced graphene oxide (rGO), and the uniform distribution of MoO2 nanodots on the rGO surface.

A selective, sensitive probe for Hg(II) ions, 7-(diethylamino)-3-methyl-2H-benzo[b][1,4] oxazine-2-thione (1), is developed. Compound 1 behaves as a ratiometric probe, exhibiting a large blue shift of 100 nm in its absorption spectra upon exposure to Hg(II) ions. The dramatic color change of the solution made ‘naked-eye’ detection of Hg(II) ions possible. Emission spectra of 1 displayed a selective enhancement in intensity in the presence of Hg(II) ions. ESI+-MS analysis indicated that Hg2+-induced desulfurization caused the large absorption response.

A facile and efficient approach to synthesize symmetric, asymmetric and bridged aromatic azo compounds (AAzos) from aromatic amines was developed by using red copper as catalyst. Despite numerous efforts towards the catalytic synthesis of symmetric and asymmetric AAzos derivatives, most reactions present certain drawbacks inhibiting their industrial applications, such as laborious multi-step processes, harsh reaction conditions and expensive reagents. And the synthesis of bridged azos had low yields before. With the presence of ammonium bromide as co-catalyst, pyridine as a ligand and molecular dioxygen as a sole oxidative reagent, red copper, a common and abundant metal in nature, exhibited unexpected catalytic activity towards the preparation of AAzos in high yields via one-step reaction, making this catalyst an attractive candidate for industrial and synthetic applications.

An efficient and environmentally friendly method for copper(0)-catalyzed oxidation of benzylamines in the presence of 1 equiv.

A novel, efficient, convenient and environmentally friendly approach for the synthesis of nitriles and imines from primary amines has been developed. Using commercially available red copper as the catalyst, ammonium bromide as the co-catalyst and molecular oxygen as the sole oxidant, nitriles and imines can be afforded in high yields through benzylic oxidation.

Aromatic azos were synthesized using unsupported ultra-thin platinum nanowires as catalysts under mild reaction conditions and the reaction mechanism was proposed.

Aromatic azos were synthesized using unsupported ultra-thin platinum nanowires as catalysts under mild reaction conditions and the reaction mechanism was proposed.

A novel ultrathin platinum nanowire with uniform length and a diameter of 1.5 nm was synthesized by acidic etching of FePt nanowire in methanol. This nanowire was characterized by high-resolution transmission electron microscopy (HRTEM). X-ray diffraction (XRD) data indicated that the main plane is (111). The ability of this nanowire to catalyze the heterogeneous hydrogenation of nitroaromatics to give the corresponding amines has been investigated. The catalyst showed satisfactory activity in various solvents under mild conditions and showed excellent stability. The catalytic performance was also evaluated in the one-pot reduction of nitroaromatics and amidation with carboxylic acids under a hydrogen atmosphere at 100 °C. These methods for the hydrogenation of nitroaromatics and the direct amidation of nitroaromatics with carboxylic acids are simple, economical, and environmentally benign, and have practical advantages for the synthesis of amines and amides without the production of toxic byproducts.

Iron oxide coated platinum nanowires (Pt@Fe(2)O(3)NWs) with a diameter of 2.8 nm have been prepared by the oxygen oxidation of FePt NWs in oleylamine. These "cable"-like NWs were characterised by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and X-ray absorption fine structure analysis. These Pt@Fe(2)O(3) NWs were used as "non-support" heterogeneous catalysts in oxidation of olefins and alcohols. The results revealed that it is an active and highly selective catalyst. Styrene derivatives were tested with molecular oxygen as the sole oxidant, with benzaldehyde successfully obtained from styrene in an absolute yield of 31%, whereas the use of tert-butyl hydroperoxide as the sole oxidant in the oxidation of alcohols led to yields of more than 80% of the corresponding ketone or aldehyde. This unsupported catalyst was found to be more active (TOF=96.5 h(-1)) than other reported Fe(2)O(3) nanoparticle catalysts and could be recycled multiple times without any notable decrease in activity. Our findings will extend the use of such nanomaterial catalysts to new catalytic systems.

A novel ultrathin platinum nanowire with uniform length and a diameter of 1.5 nm was synthesized by acidic etching of FePt nanowire in methanol. This nanowire was characterized by high-resolution transmission electron microscopy (HRTEM). X-ray diffraction (XRD) data indicated that the main plane is (111). The ability of this nanowire to catalyze the heterogeneous hydrogenation of nitroaromatics to give the corresponding amines has been investigated. The catalyst showed satisfactory activity in various solvents under mild conditions and showed excellent stability. The catalytic performance was also evaluated in the one-pot reduction of nitroaromatics and amidation with carboxylic acids under a hydrogen atmosphere at 100 °C. These methods for the hydrogenation of nitroaromatics and the direct amidation of nitroaromatics with carboxylic acids are simple, economical, and environmentally benign, and have practical advantages for the synthesis of amines and amides without the production of toxic byproducts.

A simple and scalable coordination-derived method for the synthesis of porous Co3O4 hollow nanospheres is described here. The initially formed coordination-driven self-assembled aggregates (CDSAAs) could act as the precursor followed by calcination treatment. Then the porous hollow Co3O4 nanospheres are obtained, in which the primary Co3O4 nanoparticles are inter-dispersed. When the nanospheres are used as anode materials for lithium storage, they show excellent coulombic efficiency, high lithium storage capacity and superior cycling performance. In view of the facile synthesis and excellent electrochemical performance obtained, this protocol to fabricate special porous hollow frameworks could be further extended to other metal oxides and is expected to improve the practicality of superior cycle life anode materials with large volume excursions for the development of the next generation of LIBs.

A facile and efficient approach to synthesize symmetric, asymmetric and bridged aromatic azo compounds (AAzos) from aromatic amines was developed by using red copper as catalyst. Despite numerous efforts towards the catalytic synthesis of symmetric and asymmetric AAzos derivatives, most reactions present certain drawbacks inhibiting their industrial applications, such as laborious multi-step processes, harsh reaction conditions and expensive reagents. And the synthesis of bridged azos had low yields before. With the presence of ammonium bromide as co-catalyst, pyridine as a ligand and molecular dioxygen as a sole oxidative reagent, red copper, a common and abundant metal in nature, exhibited unexpected catalytic activity towards the preparation of AAzos in high yields via one-step reaction, making this catalyst an attractive candidate for industrial and synthetic applications.

Highly-dispersed ultrafine platinum (Pt) nanoparticles supported on graphene sheets were successfully prepared. Various unsaturated compounds were reduced in excellent yields under mild conditions. Higher pressure (4 atm) accelerated the reaction rate, and complete hydrogenation products were obtained in ten minutes.

Aromatic hydrogenation to form cyclohexane derivatives is one of the most important steps in both the petrochemical industry, for clean diesel fuel generation, and the pharmaceutical industry, for safe drug synthesis. We report herein, pure ultra-thin Pt nanowire catalysts with no supporting matrix and their high activities towards the hydrogenation of aromatic compounds (>99% conversion, 1 MPa initial hydrogen pressure, 70 °C). The catalysts can also be recycled up to 40 times with no loss in activity.