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Metal‐organic frameworks recently have been burgeoning and used as precursors to obtain various metal–nitrogen–carbon catalysts for oxygen reduction reaction (ORR). Although rarely studied, Mn–N–C is a promising catalyst for ORR due to its weak Fenton reaction activity and strong graphitization catalysis. Here, we developed a facile strategy for anchoring the atomically dispersed nitrogen‐coordinated single Mn sites on carbon nanosheets (MnNCS) from an Mn‐hexamine coordination framework. The atomically dispersed Mn–N4 sites were dispersed on ultrathin carbon nanosheets with a hierarchically porous structure. The optimized MnNCS displayed an excellent ORR performance in half‐cells (0.89 V vs. reversible hydrogen electrode (RHE) in base and 0.76 V vs. RHE in acid in half‐wave potential) and Zn–air batteries (233 mW cm−2 in peak power density), along with significantly enhanced stability. Density functional theory calculations further corroborated that the Mn–N4–C12 site has favorable adsorption of *OH as the rate‐determining step. These findings demonstrate that the metal‐hexamine coordination framework can be used as a model system for the rational design of highly active atomic metal catalysts for energy applications. [ABSTRACT FROM AUTHOR]

Ethylbenzene (EB) oxidation to oxygenated products catalyzed by carbon nanotubes (CNTs) and CNTs with confined cobalt nanoparticles (Co@C/CNTs) are conducted. Co@C/CNTs with enhanced interfacial charge transfer displays a unique activity. A kinetic model with the simplified network is established, in which seven elementary reactions with prominent features of EB oxidation are selected. The main parameters, reaction rate constant (k) and active energy (Ea) are obtained. Co@C/CNTs could speed up most elementary steps and reduce energy barriers, thus improving the overall activity. The homolytic cleavage of peroxide is confirmed to be the rate‐determining step (RDS). The k ratio (1.55) of acetophenone (AcPO)/1‐phenylethyl alcohol (PEA) is found to be close to the experimental result (rAcPO/rPEA, 1.30). The prediction of EB oxidation is simulated, showing that the synthesis of AcPO dominates the reaction route, while the addition of PEA would prohibit the reaction. [ABSTRACT FROM AUTHOR]

TiO2 has garnered a flourish of interest in the field of energy storage and energy conversion. Herein, a new generation of 3D Ni foam supported in situ grown 1D TiO2 nanoarray (Ni/TiO2) is successfully prepared, through an easy solution‐phase hydrothermal process, and then CdS nanorods branched Ni/TiO2 nanoarrays are fabricated (Ni/TiO2@CdS). Their formation parameters and growth mechanism are carefully studied. Both Ni/TiO2 and Ni/TiO2@CdS monolithic catalysts exhibit advantaged photocatalytic (PC) and photoelectrocatalytic (PEC) water splitting properties compared with that of most previously reported TiO2‐based film photocatalysts. Mechanism investigation reveals that both type II and Z‐scheme charge transport mechanisms coexist in Ni/TiO2@CdS sample, and an additional Z‐scheme charge transfer effect accelerates the photogenerated charge separation and transport efficiency. This study may open a new avenue for the utilization of TiO2‐based film catalysts in a broader field of energy and environmental catalysis areas. [ABSTRACT FROM AUTHOR]

Aerobic oxidation of hydrocarbons yielding corresponding oxygenated products is one of the most important chemical processes. In current work, carbon nanotubes supported encapsulated cobalt nanoparticles with carbon layers (Co@C/CNTs) were synthesized and utilized as catalysts in the oxidation of ethylbenzene (EB) in the liquid phase, exhibiting high catalytic performance. The synergistic effect between Co@C and CNTs played the vital role on facilitating the decomposition of peroxides to enhance the overall activity. The inadequate covered Co@C on CNTs surface were considered as catalytic sites. Density functional theory revealed that the exist of Co nanoparticles could improve the interaction between the catalyst and intermediate free radicals, which were significant for EB oxidation. Last but not least, the electron transfer on carbon surface was enhanced by the incorporation of Co@C nanoparticles, which greatly improved the catalytic performance on EB oxidation. This study provides a new insight into the Co‐based catalysts in the aerobic oxidation of hydrocarbons. [ABSTRACT FROM AUTHOR]

The selective oxidation of aromatics to synthesize valued‐added products is of great significance for chemical industry. Molecule oxygen as oxidant is the priority for this process, however, low efficiency was usually obtained. In this work, a new strategy for aromatics oxidation using O2 and Tert‐butyl hydroperoxide (TBHP) as dual oxidants without catalyst was proposed. Typical radical process was observed when Toluene was used as the substrate. As high as 47.1 % conversion and 87.6 % selectivity of benzol acid were obtained, while a negligible or low activity were observed under O2 or TBHP oxidative systems. Detailed investigation shows that the distribution of products was almost the same between TBHP+N2 and TBHP+O2 processes, in which the very close active energies were obtained (46.0 and 46.3 kJ/mol). These results indicated that TBHP+N2 or TBHP+O2 involved reactions underwent the same reaction process. The mechanism study demonstrated that the decomposition of TBHP could produce abundance of t‐BuO. and.OH radicals, which significantly enhanced the αH abstraction from toluene and formed alkyl radicals. The alkyl radicals then react with O2 to produce peroxides, which started the radical propagation cycle. The overall rate would be enhanced subsequently. Furthermore, an extension application of other aromatic substrates was investigated and displayed a great promising future to produce aromatic products. [ABSTRACT FROM AUTHOR]

The electrooxidation of methanol – the anodic reaction of direct methanol fuel cells – suffers from slow kinetics. Here, we report an enhanced current density for a Pt catalyst supported on nitrogen‐doped carbon nanotube (N−CNT) decorated FeP. X‐ray photoelectron spectra show that the introduction of FeP increases the binding energy of the Pt nanoparticles. The results show that Pt/FeP15%/N−CNT displays a 3.4 times higher forward peak current density compared to commercial Pt/C. The improved performance is attributed to a change in the electronic state of the Pt nanoparticles through the electronic interaction between Pt and FeP, evidenced by the mitigated CO poisoning. [ABSTRACT FROM AUTHOR]

Selective hydrogenation of biomass 5‐Hydroxymethylfurfural (HMF) to 2, 5‐dimethylfuran (DMF) which is a suitable candidate for liquid fuel has been widely concerned. Developing efficient and economic catalysts for the hydrogenation of HMF to DMF under mild conditions is a crucial issue. Here series monometallic Cu‐based catalysts were synthesized from controlled thermolysis of Cu‐BTC metal‐organic frameworks and characterized by TG, N2 adsorption‐desorption, XRD, XPS, SEM, TEM, and H2‐TPR techniques. The CuOx@C catalyst with Cu2O/Cu composites enwrapped in porous carbon matrix derived from Cu‐BTC by two steps thermolysis treatment shows high hydrogenation activity with 100% conversion of HMF and 92% selectivity of DMF at 180 °C under 3 MPa H2 pressure. The oxidation treatment following up the thermolysis of Cu‐BTC under inert atmosphere increases the content of Cu+ in the catalyst and improves the activity of the catalyst, which is mainly owe to the synergetic effect between Cu+ and Cu0. [ABSTRACT FROM AUTHOR]

In this study it is demonstrated that carbon nanotubes (CNTs) with doped nitrogen atoms in graphitic domains (NCNTs) can act as a new class of metal-free catalysts exhibiting excellent activity in the aerobic oxidation of cumene. We proved that NCNTs can promote the decomposition of hydroperoxide cumene with exceptionally high activity, resulting in strongly increased cumene conversion and extraordinarily high selectivity to acetophenone and 2-benzyl-2-propanol. The incorporation of nitrogen altered the surface electron structure of the CNTs and tuned the reactivity and selectivity. DFT calculations revealed that the remarkable improvement of catalytic performance of NCNTs is caused by the strong interaction between hydroperoxide cumene and the NCNTs. NCNTs also exhibited desirable recyclability after four cycling tests. This study not only provides a novel method for the cumene oxidation to high-value-added products at moderate reaction temperatures and oxygen atmospheric pressure, but also gives new insights into the effect of surface nitrogen doping on carbon-catalyzed liquid-phase oxidation of aromatic hydrocarbons. [ABSTRACT FROM AUTHOR]

The Cover Feature shows that compared to pure carbon, nitrogen doping retards the superoxide disproportionation in the oxygen reduction reaction in an alkaline medium, thereby promoting the energy conversion efficiency. More information can be found in the Communication by Li et al. on page 1133 in Issue 6, 2019 (DOI: 10.1002/cssc.201802601). [ABSTRACT FROM AUTHOR]

Phosphorus-doped graphitic-C3N4 nanosheets coupled with BiPO4 nanorods are hydrothermally synthesized from aqueous solutions containing CH2N2, NaH2PO4, Bi(NO3)3, and HNO3 (autoclave, 483 K, 4 h), followed by calcination at 823 K for 4 h. [ABSTRACT FROM AUTHOR]