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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]

Cyclo[18]carbon (C18) as a special molecular allotrope of carbon composed of two‐coordinate carbon atoms has recently been manufactured and characterized by atomic manipulation. Herein, we analyze the electrochemical reduction characteristics of carbon dioxide (CO2) on typical carbon materials (graphene, C60, carbon nanotubes and C18) using density functional calculations. Encouragingly, C18 shows excellent CO2 reduction activity compared to other carbon materials. [ABSTRACT FROM AUTHOR]

Superoxide decay behavior is evaluated by contrastive potential energy surface analyses from theoretical calculations. The presence of carbon surfaces enhances the superoxide decay through disproportionation instead of electroreduction, which is a non‐electrochemical reaction that impedes the increase in energy efficiency for relevant energy conversion applications. Nitrogen doping of carbon effectively retards the disproportionation by influencing the oxygen stretching vibration and changing the proton‐coupled electron transfer trend. OK with O2−decay: Superoxide decay is evaluated by contrastive potential energy surface analyses from theoretical calculations. Carbon surfaces enhance superoxide decay by disproportionation instead of electroreduction, which impedes application for energy conversion. Compared to pure carbon, nitrogen doping retards superoxide disproportionation, promoting energy conversion efficiency. [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]

It was reported for the first time that carbon nanotubes (CNTs) as metal-free catalyst exhibited an excellent activity in the selective oxidation of ethylbenzene (EB) to acetophenone (AcPO) in the liquid-phase with oxygen as the oxidant. The reasonable mechanism responsible for the liquid-phase oxidation of EB on CNTs was proposed. The results demonstrated that the CNTs played an important role in the decomposition of 1-phenylethyl hydroperoxide (PEHP) and contributed to the production of AcPO, owing to π-π interactions between the radical species and peroxides and the graphene sheets of the CNTs. Surface carboxylic groups of the CNTs were unfavorable to EB oxidation. Adsorption energies of the radical species and peroxides on pristine and modified CNTs with carboxylic groups were calculated by DFT. These theoretical calculations were well consistent with the experimental results, and also supported the presented mechanistic pathway of EB oxidation on CNTs. This study not only presents a facile and effective alternative to cobalt-based catalysts for the selective oxidation of EB to AcPO but also gives new insight into the effect of surface structures on carbon-catalyzed reactions, and further pushes forward the research on carbon catalysis. [ABSTRACT FROM AUTHOR]

Biomass char (BC) deriving from fast pyrolysis of biomass was a potential adsorption material due to its relative high fixed-carbon content and the inherent porous structures. Adsorption of phosphate from aqueous solution by BC was investigated in this paper. The results showed that the adsorption capacity of BC was dependent on pyrolysis conditions, such as temperature and holding time. The maximum adsorption capacity for phosphate was approximately 15.11 mg g−1 at 298 K. The pseudo-second order model of the adsorption kinetics indicated that the adsorption process was complex and several mechanisms were involved. Equilibrium isotherm was satisfactorily followed the Freundlich isotherm model. The KF value in Freundlich equation gradually increased with elevating temperature. Moreover, the thermodynamic constants: Δ G0, Δ H0, and Δ S0 were evaluated as −6.49 kJ mol−1 (at 298 K), 13.41 kJ mol−1, and 66.70 J mol−1 K−1, respectively. Phosphate adsorption onto BC was spontaneous and endothermic. As a waste, BC was a potentially attractive adsorbent for phosphate removal from aqueous solution with low cost and high capability. [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]