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The superior performance of WO3–SBA-15 for epoxidation was attributed that the abundant isolated WO4 benefited the coordination and activation of H2O2, and strong electron-withdrawing by the support facilitated weakening the bond strength of the O–O bond in W–OOH.

In the production of polyacrylonitrile-based carbon fibers (PAN-CFs), preoxidation is a key step to improving the thermal stability of the fibers and forming their structural prototype. However, structural evaluation of PAN fibers during preoxidation remains ambiguous, partly due to a lack of in situ studies. This contribution reports an in situ study of the preoxidation of PAN fibers using wide-angle X-ray scattering and small-angle X-ray scattering techniques on a synchrotron radiation beamline. The structural changes of the skeleton and pores in the fibers are revealed and correspond to five kinds of diffraction spots (peaks) and two kinds of scattering streaks, respectively. The preoxidation shows obvious stages, and the corresponding possible mechanism is analyzed.

Carbonization is an effective way to achieve the comprehensive utilization of coal. However, the in situ variation of graphite-like microcrystals, the basic structure of coal macromolecules, with heating and cooling during carbonization has not been fully characterized so far. Anthracite is a type of humic coal with the highest degree of coalification, and its structure change can be monitored well by X-ray scattering or diffraction techniques. In this contribution, an in situ synchrotron radiation wide-angle X-ray scattering (WAXS) study on high-temperature (1200°C) carbonization of a high-quality anthracite mined in Jincheng, China, is presented. The results show that, during the continuous process of heating and cooling, the size and height of the aromatic lamellae first decrease and then increase with minima at 900 and 1000°C, respectively, while the interlayer spacing first increases and then decreases with a maximum at 1000°C. The roadmap of graphite-like microcrystalline structure change during the whole continuous process of heating and cooling is revealed and described.

In-depth research has found that the nanocrystal facet of transition metal oxides (TMOs) greatly affects their heterogeneous catalytic performance, as well as the property of photocatalysis, gas sensing, electrochemical reaction

The design and fabrication of efficient catalysts for ammonium perchlorate (AP) decomposition is crucial for the performance of composite solid propellants. Herein, a novel hierarchical structure material of Cu-WO3 nanowire arrays on a nanoflower flake (Cu-WO3 NANF) was synthesized by a facile hydrothermal reaction. The negatively charged (001) polar facets of hexagonal WO3 and the action of Cu2+ induced growth were two important factors for the formation of hierarchical structures. The Cu-WO3 NANF exhibited remarkable catalytic activity for the thermal decomposition of AP. The temperature and activation energy of high temperature AP decomposition were significantly decreased to 378.3 °C and 147.01 kJ mol−1, respectively, which are attributed to the more oxygen vacancies and lower band gap energy of the Cu-WO3 NANF. Thus, it was excited at a lower heat to produce activated species. Under the strong adsorption of Cu-WO3 NANF surface Lewis acid, the activated species can react with NH3 quickly and deeply to produce N2, N2O, NO2 and NO gases, accompanied by a heat release of up to 1118 J g−1. The proposed catalytic mechanism was further corroborated by the in situ TG-MS result. This facile strategy provided a new idea for the design of hierarchical catalysts, and our research opened up a new field for WO3 applications.

The introduction of oxygen vacancies improved 1-hexene epoxidation performance over WO3−x/SBA-15 catalysts, which is attributed to the enhanced Lewis acidity of the active centers and the reduced energy barrier of the rate-determining step.

The catalytic liquid-phase oxidation of 1-hexene with O2 using Ag/porous bowl-shaped alumina shows good selectivity for the epoxidation product.

A new strategy was developed to control the exposed facets of α-Fe2O3 through oriented attachment along the [001] direction by utilizing the polar {001} facets of α-Fe2O3, and the facet-dependent catalytic performance was explored.

Polyacrylonitrile (PAN) based carbon fibers possess high performance and wide applications. Preoxidation, as one of the crucial steps in the preparation of carbon fibers, refers to the process in w...

Coal is an important energy and chemical raw material. Carbonization is an effective way for comprehensive utilization of coal, especially for coal with coking capability. The complex pore structur...

Glycerol can be dehydrated with methanol to produce methyl glyceryl ethers as biologicals and diesel fuel additives. Considering the high efficiency of mass transfer and product separation in the gas-solid catalytic process, a fixed-bed continuous-flow reactor was used to carry out the catalyst evaluation test of the process at 564 K. Compared with zirconium sulfate, lanthanum nitrate, and ammonium molybdate, phosphotungstic acid exhibits a higher target product selectivity. Through loading experiments, it was found that the optimal loading fraction of phosphotungstic acid on alumina is 10 wt %. After the alumina carrier is impregnated with nitric acid, the selectivity and yield of monomethyl glycerol ether can be effectively improved, and it has little effect on other products. A test of the addition amount of cerium nitrate as a promoter was carried out. It was shown in the test that when the addition amount of cerium nitrate is 10 wt %, the catalyst life increases from 2 to 3.5 h and the selectivity of dimethyl glycerol ether increases to 54.51%, which is twice the original. However, the selectivities of monomethyl glycerol ether and trimethyl glycerol ether decrease by one-half each. Through catalyst characterization, it was shown that carbon deposition on the catalyst surface is one of the reasons for catalyst deactivation.

Wide-angle X-ray scattering (WAXS) is routinely used to characterize the ordered structure in materials. The measured angles are generally calibrated by using standard samples with several diffract...

The change in the fractal structure of anthracite mined in Jincheng, China, during high-temperature (1200°C) carbonisation was studied in situ by small-angle X-ray scattering (SAXS) at Beijing Sync...

The confinement effect known as efficient strategy to enhance the heterocatalytic activity and stability, but a clear view regarding the role of encapsulated overlayers is far from convincing at present, especially, the penetration of substrates with different size. Herein, the experimental evidence about the impacts of BN overlayers on hydrogenation is obtained over Co@BN/BN model catalysts with tuned thinness, in which BN overlayers encapsuled Co particles that dispersed on the defective BN supports, fabricating by the nitridizing of ball-milled BN microplates under NH

In catalytic reactions, a large specific surface area usually means more active sites. Hollow structures can provide lots of surface sites to catalyze the reaction or fix the reaction center, but the preparation process is mostly complex. In this work, using NH4+ as a structure-directing agent and ascorbic acid (AA) as a reducing agent, combined with the self-transformation process of metastable aggregated particles and the local Ostwald ripening mechanism, hollow Cu2O nanospheres with a large specific surface area (30.9 m2 g−1) were rapidly synthesized by a one-step method at low temperature. In the thermal decomposition of ammonium perchlorate (AP), it was found that the decomposition temperatures at low temperature and high temperature decreased by 31.6 °C and 125 °C, respectively. Compared with pure AP, the heat release increased by 1.5 times, and the reaction activation energy reduced by 56.0%. This is because the Cu2O hollow spheres have a larger specific surface area, and the adsorption capacity is improved owing to the loose and porous structure. The catalytic area and active sites for continuous reaction are increased, and thus the Cu2O hollow spheres exhibited excellent catalytic performance.

Micron-sized Fe3O4 is a practical anode material that is used in industrial Ni–Fe batteries, and its ability to simultaneously achieve high capacity and excellent rate capability is very practical and is urgently needed. In this work, through etching industrial Fe3O4 particles, hydrophobic mesoporous Fe3O4 sheets can be regenerated, and can be dispersed around micron-sized Fe3O4 particles when the slurry dries to form a coating on the current collector. These hydrophobic mesoporous sheets in the electrode can improve the electrochemical reaction kinetics and alleviate the volume expansion of micron-sized Fe3O4 particles, which is a new and effective way to simultaneously achieve high capacity and excellent rate capability. Our results show that when this electrode is coupled with the NiS cathode, the battery exhibits the capacity of 221.17 mA h g−1 at 0.2 A g−1, and excellent cycling stability of 92% of the initial capacity after 50 cycles, revealing significant performance improvement. Compared with the common strategy of carbon-coating Fe3O4 particles to improve the battery performance, this strategy of functionalizing Fe3O4 particles with hydrophobic mesoporous sheets is more favorable for performance improvement and large-scale application.

The changes in fractal structure during high-temperature (1200°C) carbonisation of a Chinese non-caking coal were studied in situ by synchrotron radiation small-angle X-ray scattering (SAXS). The r...

In this work, ultrathin nanosheet-assembled, phosphate ion-functionalized NiO (P-NiO) microspheres were prepared via a facile hydrothermal reaction and subsequent thermal annealing. The formation m...

The oxidative desulfurization (ODS) of fuel oils is of great significance for environmental protection, and the development of efficient ODS heterogeneous catalysts is highly desired. Herein, we ha...

The ethanol oxidation reaction is of critical importance to the commercial viability of direct ethanol fuel cell technology. However, owing to the poor C-C bond cleavage capability, almost all ethanol oxidation is incomplete and suffers from low selectivity toward the C1 pathway. Herein, under the support of theoretical calculations that the heterointerfaces between CoP and Pd can reduce the energy barrier of C-C bond cleavage, rich heterointerfaces in CoP/RGO-Pd hybrids were designed to improve ethanol electrooxidation performance through enhancing the selectivity toward the C1 pathway. The experimental results show that the faradaic efficiency of the C1 pathway of CoP/RGO-Pd hybrids is as high as 27.6%, surpassing most reported catalysts in the literature. As a result of this enhancement, CoP/RGO-Pd10 exhibits mass activity as high as 4597 mA·mg

The metal-free BN catalyst is a competitive candidate in oxidative dehydrogenation (ODH). The popular oxidant used is molecular O2, and the alternative soft oxidant, CO2 with better selectivity, is...

A series of Fe/h-BN catalysts promoted with Cu or Mn were prepared for Fischer-Tropsch synthesis (FTS). The physicochemical properties, crystal structures and morphologies of the catalysts were characterized by N2 physisorption, FT-IR, TPR, XPS, XRD, MES and TEM. It is found that iron oxide nanoparticles are highly dispersed on h-BN matrix due to the anchoring effect of surface defects and the accommodation of porous structures of h-BN. The characterization results indicate that strong interaction between iron oxide and h-BN is present on un-promoted catalyst, which endows the h-BN supported iron catalyst with stable properties under FTS conditions but severely retards reduction of the catalyst. The addition of Cu to Fe/h-BN can to some extent overcome the strong interaction by introducing more sites for dissociating H2. It is observed that Cu promoter can increase the reduction or carburization degree and thus enhance the FTS activity. The addition of Mn to Fe/h-BN can weaken the strong interaction by altering the electron structure of iron species. And the electron-rich Fe species are responsible for easy reduction and the enhanced FTS performance. Besides, a higher activity can be realized by co-adding Cu and Mn to the Fe/h-BN catalyst. These results suggest that the synergistic effect of Mn and Cu can largely improve the performance of Fe/h-BN catalyst without impairing the stability of the catalyst. The present study paves a way to tailor the performances of FTS catalysts with h-BN as support.

For crystalline catalysts with special morphology, the corners and edges are usually of high activities due to the presence of unsaturated coordination sites, so it will be an ideal strategy to promote catalytic properties by only keeping the corners and edges of such kinds of catalysts. In this work, a Cu2O tetradecahedral nanocage with plenty of corners and edges was formed by selectively etching the (111) and (100) facets on the basis of a simple top-down method, in which SDS was used as a protective agent to keep the active corners and edges while hydroxylamine hydrochloride was used as a reducing agent and an etchant. The decomposition of ammonium perchlorate (AP) was used as a probe reaction to test its catalytic performance. It was found that the low temperature decomposition (LTD) and high temperature decomposition (HTD) were reduced by 27.1 °C and 107 °C, respectively, and the heat release increased by three times in comparison with pure AP. The Cu2O nanocage exhibits excellent activity and high catalytic performance in the reaction. This work provides us an effective AP thermal decomposition catalyst and a simple strategy to fabricate a hollow structure with low-energy facets etched and highly active facets exposed.

Porous Co3O4 nanoplates constructed by loosely interconnected nanoparticles were synthesized via an L-lysine assisted hydrothermal treatment and subsequent thermal annealing. The hydrothermal conditions of reaction time, reaction temperature and reactant concentrations were investigated in detail. The results suggested that the high affinity of L-lysine could effectively control the redissolution–recrystallization and even restrict the dehydration–condensation reaction of the Co(OH)2 precursor, and thus played the key role for the preparation of the resulting porous Co3O4 nanoplates. Cyclic voltammetry and amperometric methods were used to evaluate the electrochemical performance of the resulting porous Co3O4 nanoplates toward glucose sensing in an alkaline medium. The sensors constructed by the porous Co3O4 nanoplates exhibited a fast response time (within 5 s), a detection limit of 2.7 μM, a sensitivity of 212.92 μA cm−2 mM−1, a linear range from 0.05 mM to 3.2 mM and good stability at a low applied potential (0.38 V vs. Ag/AgCl), suggesting its high performance towards non-enzymatic glucose sensing.

In this study, porous activated carbon balls supported by nanoscale zero-valent iron composites (Fe@PACB-700) were used for the first time for the removal of trace Cr(VI) from aqueous solutions. The Fe@PACB-700 composites were prepared by a facile carbothermal reduction method and then characterized by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS). The results show that nZVI particles have been successfully loaded onto PACBs. Fe@PACB-700 shows an excellent Cr(VI) removal efficiency of 91.2%. The maximum adsorption capacity of Fe@PACB-700 for Cr(VI) is 22.24 mg/g, which is 4.36 times that of PACB. The residual Cr(VI) concentration is below 20 ppb with the use of 0.15 g of Fe@PACB-700, which is much lower than the allowable concentration for Cr(VI) in drinking water (0.05 mg/L). The adsorption of Cr(VI) can be well described by the Langmuir isotherm model and pseudo-second-order kinetic model. Fe@PACB-700 still has a high removal efficiency of 80% after five cycles. Thus, Fe@PACB-700 has a great potential for Cr(VI) removal from aqueous solution. Graphical abstract.

Boron nitride (BN) has attracted great attention with an unexpected ability in aerobic catalysis. Still, its related probe reactions are relatively rare, and the effect of the BN-supported metal catalyst on O2 activation is still ambiguous, and opinions are varied. In this work, the porous BN (pBN)-supported Au catalyst with a porous structure and exposed edges exhibits high activity in the oxidative cross-esterification reactions between the aromatic and C1-C3 aliphatic alcohols at ambient temperature. The turnover frequency value for methyl benzoate is 118 h-1 at 30 °C, and the calculated apparent activation energy (Ea, 58 kJ/mol) is comparable to that of AuPd/TiO2, Ru/Al2O3, and PdBiTe catalysts. Combined with temperature-programmed desorption (TPD) results, the loading of Au enhances the desorption of O2 and the interaction with alcohols; thus, a synergistic effect between the O-rich pBN and Au is considered. The free-radical scavenger can dramatically suppress the conversion (∼6%), suggesting that the reaction proceeds via the O2* radicals. According to the vibration of νO-O, δOO-H, and νB-O-O-B detected by attenuated total reflectance-infrared spectroscopy (ATR-IR), we are prone to consider the oxygen activation route by the edge B atoms. Then, a possible L-H reaction mechanism was proposed: benzyl alcohol and O2 adsorb on the Au/pBN initially, then O2 is converted to O2*, and the α-H elimination proceeds; as the semi-acetal formed, another α-H elimination proceeds and methyl benzoate is finally formed.

The surface chemistry of catalyst plays a vital role in the catalytic process. And the effects of surface groups of porous boron nitride (p-BN) on the hydrogenation reaction have not been studied in detailed. In this work, two main surface species of Co/p-BN catalyst were tuned thermally and their roles on the hydrogenation reaction were discriminated by α, β-unsaturated aldehyde hydrogenation reaction. The surface B O content decreased at higher reduction temperature and the cobalt phase changed from CoO to the mixture of CoO and Co0. The Co/p-BN-500 exhibited the highest selectivity to C O hydrogenation. And its turnover frequency (TOF) of 13.2 h−1 is close to the optimal value of reported cobalt catalysts. When the reaction proceeds, hydrogenation rate of C O increases but that of C C decreases gradually, thus a surface groups variation was expected at the initial period. Further in-situ FTIR spectra showed the band intensity of edge N H increases as the adsorption proceeds at 50°С but it decreases as the temperature rise to 200°С, in combined with the shift of C O adsorption peak, a intermolecular hydrogen bond between edge N H and the terminal C O group was suggested, which account for the better selectivity to C O than C C.

Coating actives with carbon is an effective way to improve the performance of Ni Fe battery, and relevant study has focused on the nanoFe/FeOx, while the micron particles used in the industry have been usually ignored. Herein, we achieve the uniform and thickness-controllable carbon coating for the micron-sized dodecahedral Fe3O4, and study the influence of the carbon thickness on the performance of the Fe anode in details. As a result, capacity, rate performance and stability are improved with the increase of carbon coating because of lower charge-transfer resistance and more complete structure. However, for the first plateau (Fe0→Fe2+) which is typically applied in the industry, the improvement of the carbon coating is limited with the thickness of the carbon, owing to insufficient impact of mitigating passivation. For the second and third plateaus (Fe2+→Fe3+), with the increase of the carbon coating, the capacity and rate performance are both markedly improved because a more completed structure can better promise the conductivity. As the thickness of the carbon coating is 20 nm, the electrode exhibits 141 mAh g−1 at a high current density of 36 A g−1. These results are of great significance to the development of industrial Ni-Fe battery.

Herein, MoO3 nanowires (Fe–MoO3 NWs) along the [110] direction were successfully synthesized in the presence of Fe3+ cations. The Fe–MoO3 NWs present a large specific surface area of 174.7 m2 g−1 and rich surface –OH groups, and the possible formation mechanism of such a structure is due to the adsorption of Fe3+ cations toward non-(110) planes of MoO3 in solution with pH greater than its isoelectric point. The obtained Fe–MoO3 NWs show excellent and highly selective adsorption capacity toward quasi-phenothiazine dyes (methylene blue, toluidine blue, azure I, and acridine orange). The dye removal rate could reach 99% in 3 min, and the maximum adsorption capacity is up to 144.3 mg g−1 and the adsorption is up to 28.86 mg g−1 per minute, which is 11 times greater than that of pure MoO3 and far greater than that of the recently reported MoO3 nanostructures. This excellent selective adsorption performance of Fe–MoO3 NWs was mainly attributed to the enhanced chemical adsorption of quasi-phenothiazine dyes by rich surface –OH groups and Fe species through hydrogen bond and coordination bond adsorption with N and S, respectively, which was confirmed by adsorption isotherms and adsorption kinetics. These results suggest the potential application of Fe–MoO3 NWs in the field of water pollution treatment.

Cerium dioxide (CeO2) octahedra were synthesized by a facile microwave-assisted hydrothermal method. The structure and morphology were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that octahedra were enclosed by eight (111) facets with an edge length of 180 nm. The possible growth mechanism of CeO2 octahedra was proposed by adjusting the reaction temperature, solvent, molar ratios of polyvinyl pyrrolidone (PVP)/Ce3+ and reaction time. The formation of the octahedra was attributed to the oxygen terminated structure of (111) facets and the steric hindrance effect of PVP. Furthermore, the catalytic activity of CeO2 octahedra on the thermal decomposition of ammonium perchlorate (AP) was investigated by thermogravimetry and differential scanning calorimetry (TG-DSC). Compared with cubes, the CeO2 octahedra exhibited enhanced activity on the decomposition of AP. Upon addition of 4 wt% CeO2 octahedra, the ending mass loss temperature of AP decreased by 52.1 °C. The higher catalytic activity was attributed to the synergistic effect between the exposed (111) facets and high concentration of oxygen vacancies that arised from the mixed valence state of Ce ions.

Nitrogen doping is an efficient strategy to improve the catalytic activity of carbocatalysts in direct dehydrogenation reactions. The interpretation of enhanced activity is now mainly attributed to the strengthened basicity. On the other side of doping, electronic properties that differed in various nitrogen doping configurations, however, were barely considered. Herein, to elucidate the role of graphitic N, pyridinic N and pyrrolic N, N-doped porous carbon balls with tunable contents of these nitrogen species were used as moulded carbocatalysts for steam-free direct dehydrogenation of ethylbenzene to styrene. Along with C O groups that were commonly certified as active sites on carbocatalysts, graphitic N contributes to the styrene yield. The former serves as active site that directly activates and dissociates C–H bond, while the latter one provides additional electrons into the delocalized π-system and leads to improved chemical reactivity of C O. The loss of C O active sites is not only attributed to the carbon deposition as illustrated by the elevated area ratio of D3 to G band in Raman spectra, but also its failed regeneration from intermediate hydroxyl groups (C–OH), which was proved by the tiny thermal decomposed products of CO and H2O as detected by the on-line mass spectrometry and gas chromatography.

Although significant progress has been made in WO3 hollow spheres, it is still a challenge to synthesize WO3·0.5H2O hollow spheres. Herein, a strategy for the preparation of well-shaped WO3·0.5H2O hollow spheres was developed by a facile bubble-template method using urea as a foaming agent in the solvothermal process with EtOH–H2O mixture solvent. In this process, the growth of WO3·0.5H2O nanoparticles is limited by N-containing organic compounds, thus these nanoparticles tend to agglomerate along the surface of bubbles (CO2 and NH3) to fabricate hollow spheres with pores formed in the wall, and after low temperature calcination, pure WO3·0.5H2O hollow spheres are obtained. The obtained WO3·0.5H2O hollow spheres exhibit enhanced activity in catalytic oxidation of benzyl alcohol to benzaldehyde: the conversions of benzyl alcohol, 4-methyl, 3-methyl, 2-methyl, 4-bromo and 4-nitro benzyl alcohol are 99.2%, 95.0%, 97.1%, 86.7%, 98.0%, 90.6%, respectively, and the selectivities to corresponding benzaldehydes are all greater than 98%. The high activity of WO3·0.5H2O hollow spheres could be attributed to surface –OH groups and the hollow and porous structure.

Hematite (α-Fe2O3) is regarded as one of the most promising photocatalysts, but its photocatalytic activities have always been limited to the pristine form because of poor charge separation efficiency. In the present work, a new kind of dodecahedral α-Fe2O3 particle (DoFe) enclosed by six (012) and six (104) facets provides us with a clue to solving this problem, because the coexistence of these two facets brings about a better photocatalytic performance than that for crystals exposing only a single facet. The results show that, in addition to surface structures, photogenerated charge separations between anisotropic facets also have an influence on photocatalytic activities. Furthermore, particle size could be precisely regulated, which is helpful for ruling out the possible specific contribution of edges and vertexes. These results are of great importance for our understanding of the relationship between morphology and activities, and can direct us to synthesize a high-efficiency catalyst.

High temperature carbonization, an important approach to cleanly and efficiently use coal, refers to a complex process in which a series of physical phenomena and chemical reactions occur when coal is heated to ≥1000 °C in anoxic conditions. A furnace was developed for the in-situ small angle X-ray scattering (SAXS) and wide angle X-ray scattering (WAXS) measurements with the scattering angle 2θ between 0° and 60° during sample heating from room temperature to 1200 °C. The usefulness of the furnace for high temperature carbonization of coal was verified at the 1W2A SAXS station at the Beijing Synchrotron Radiation Facility (BSRF).

The oxidative desulfurization (ODS) of fuel oils is of great significance for environmental protection, and the development of efficient ODS heterogeneous catalysts is highly desired. Herein, we have designed and synthesized a novel material of amorphous Cr

Radio frequency (RF) power in the ion cyclotron range of frequencies (ICRF) is one of the primary auxiliary heating techniques for Experimental Advanced Superconducting Tokamak (EAST). In this paper, we will present an overview of the main experimental results from recent campaign on EAST. 1) A dedicated experiment for more than 10MW operations has been carried out on EAST. The major aspects linked to the use of the EAST auxiliary heating systems: ICRF,LHCD and NBI are presented with emphasis on ICRF and LH. The challenges for ICRF coupling on EAST will be described at the low densities typically used for long pulse operation with lithium wall conditioning. 2)This paper also summarizes effects of ICRF power on LH coupling and modification of heat loads on EAST. 3) Co-current rotation driven by ICRF are observed in both L-mode and H-mode discharges. Co-current rotation can be generated by ICRF heating in LHCD plasma. Different rotation behavior observed in LHCD discharges. ICRF can also induce counter-current rotation in LHCD L-mode discharges. 4) A high-frequency magnetic probes (HFBs) system has been developed and successfully applied to detect ion cyclotron emission (ICE) in D-NBI injection experiments in the 2018 experimental campaign of EAST. ICE driven by fast D-NBI ions and fusion born ions are observed on EAST.5) In Hydrogen minority in Deuterium plasma, the interaction of fast wave and fast D-NBI ions is detected on EAST. Acceleration of fast D ions is confirmed by increased neutron yield.

The development of efficient and low-cost hydrogen evolution reaction (HER) catalysts is critical for energy storage and conversion devices. Herein, we develop a facile method to fabricate a novel hybrid by in situ growing CoP porous nanoplates on reduced graphene oxide (RGO). The hybrid shows excellent HER performance in acid media with a low Tafel slope of 57 mV dec−1, small onset overpotential of 76 mV and long-term durability with 86.3% current density retention after 10 h electrocatalysis. The superb HER activity can be ascribed to the unique structure of porous hexagonal nanoplates. On the one hand, the porous structure provides abundant active sites for HER. On the other hand, hexagonal nanoplates provide large contact with RGO, enhancing the charge transfer ability. In addition, the hybrid with such structure shows good stability under ambient atmosphere and can maintain the initial HER activity even after six months of storage. This work demonstrates that large contact between active component and conductive support is not only beneficial to the HER activity and durability, but also beneficial to the stability of material itself.

Rational design of supported noble metal is of great importance for highly efficient heterogeneous catalysts. On the basis of the distinct adsorption characteristics of noble metal and transition-metal oxides toward O2 and CO, the overall catalytic performance of CO oxidation reaction could be further modified by controlling the surface property of the materials to achieve optimal adsorption activity. Here, we studied the influence of facets matching between both platinum and ferric oxide support on CO conversion efficiency. It shows that the activities of four catalysts rank following the order of Pt{100}/α-Fe2O3{104} > Pt{100}/α-Fe2O3{001} > Pt{111}/α-Fe2O3{001} > Pt{111}/α-Fe2O3{104}. The strong metal–support interaction and adsorption energy varying with matched enclosed surface are demonstrated by density functional theory based on the projected d-band density of states. Compared with the other three cases, the combination of Pt{100} and α-Fe2O3{104} successfully weakens CO poisoning and provides pro...

Rational design and optimization of metal-free electrocatalysts for the oxygen reduction reaction (ORR) is crucial for fuel cells and metal-air batteries. However, identifying design principle that links the active sites and their synergistic effects is far from satisfactory, especially for B,N-codoped graphene. Herein, we provide four B,N-codoped porous graphenes with tunable contents of pyridinic N, graphitic N, BC3 and C-B(N)O. BC3 shows multiple-fold specific activity compared with graphitic N and pyridinic N, while C-B(N)O offers no positive contribution. Density functional theory calculations indicate that the synergistic effect between graphitic N and BC3 can effectively facilitate the reduction of O2. These pinpoint that graphitic N and BC3 are the main active sites among various nitrogen or/and boron doping configurations. The most active catalyst exhibits superior activity than the commercial Pt/C catalyst using the RDE method in alkaline media, and displays comparable power density to Pt/C catalyst in Zn-air battery.

BN nanosheets (BN) have drawn great attention in heterogeneous catalysis recently, and their defects have a profound effect on the key performance of the catalyst, but it has been overseen and little addressed. Here, three Fe/BN nanosheet (Fe/BN) catalysts were prepared BN with varied B–O surface defects. Fischer–Tropsch synthesis, a key industrial process, was taken as an example. It is found that the rich B–O defects not only resulted in decreased crystal size and low crystallinity of the Fe2O3 but also showed enhanced interaction with the active component and support. As a consequence, the three Fe/BN catalysts showed a dramatic difference in catalytic performance. Our studies reported here could be a guide for the rational design of the highly efficient hydrogenation BN-based catalyst.