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The selective oxidation of methane into methane oxygenates such as CH3OH and HCOOH with O2 is a promising technology for direct methane conversion. This study successfully demonstrates the partial oxidation of methane over Pd−Fe/ZSM‐5 catalysts in water, where H2O2 was generated in situ from H2 and O2. A low Pd content is essential for preventing agglomeration of Pd nanoparticles, and intimate contact between Pd and Fe species is beneficial for achieving high yields of methane oxygenates. This one‐body catalyst showed better catalytic performance than that of previously reported ones, especially at low temperatures. 0.28 %Pd–0.56 %Fe/ZSM‐5 exhibited a stable catalytic performance in a continuous flow reactor. [ABSTRACT FROM AUTHOR]

The electrochemical activation of CuInS2/MoSx for photoelectrochemical (PEC) H2 production was revealed for the first time through in operando Raman spectroscopy. During the activation process, the initial metallic MoSx phase was transformed to semiconducting MoSx, which facilitates charge carrier transfer between CuInS2 and MoSx. Ex situ X‐ray photoelectron spectroscopy and Raman spectroscopy suggest the existence of MoO3 after the activation process. However, apart from contradicting these results, in operando Raman spectroscopy revealed some of the intermediate steps of the activation process. [ABSTRACT FROM AUTHOR]

Direct conversion of methane into value‐added chemicals is a challenging but worthwhile subject. In this communication, the direct conversion of methane into methane oxygenates was achieved in an aqueous solution at room temperature using iron salts and Pd/C as catalysts and hydrogen peroxide as an oxidant. The hydrogen peroxide can be directly added or generated in situ from hydrogen and oxygen. The Pd/C catalyst greatly enhanced the reaction rate together with the iron salts. The effect of some parameters such as reaction temperature, reaction time, pH, acid type, and catalyst amount on the yields of the methane oxygenates was also investigated. When hydrogen peroxide was directly added, the turnover frequency (TOF), defined as the moles of methane oxygenates per moles of Fe per unit time, at 293 K was 29 h−1 at pH=2.3. The TOF at 293 K was 42 h−1 at pH=1.3 with in situ generated hydrogen peroxide from hydrogen and oxygen. [ABSTRACT FROM AUTHOR]

The selective oxidation of methane into methane oxygenates such as CH3OH and HCOOH with O2 is a promising technology for direct methane conversion. This study successfully demonstrates the partial oxidation of methane over Pd−Fe/ZSM‐5 catalysts in water, where H2O2 was generated in situ from H2 and O2. A low Pd content is essential for preventing agglomeration of Pd nanoparticles, and intimate contact between Pd and Fe species is beneficial for achieving high yields of methane oxygenates. This one‐body catalyst showed better catalytic performance than that of previously reported ones, especially at low temperatures. 0.28 %Pd–0.56 %Fe/ZSM‐5 exhibited a stable catalytic performance in a continuous flow reactor. [ABSTRACT FROM AUTHOR]

The catalytic activity of metal oxide-supported Pt-MO x (M=Mo, W, Ce, V) catalysts was investigated for methanol reforming to hydrogen at low temperatures with varied reaction pressures in gaseous to aqueous phase regimes. The Pt-MoO x/TiO2 catalysts prepared through co-impregnation of the precursors demonstrated unprecedentedly high catalytic activities compared with the previously reported Pt-based catalysts, which showed an order of magnitude higher hydrogen production turnover rates with extremely low CO selectivities. The morphological and electrochemical characteristics of the dispersed Pt-MoO x nanoclusters were largely affected by the impregnation method and the Mo/Pt atomic ratio. The Pt-MoO x nanoclusters consisting of metallic state Pt and MoO x moieties of high site density and reducibility capable of Mo6+ to Mo5+ redox transition promoted the marked rate enhancements in methanol reforming to hydrogen at low temperatures. These highly active catalysts offer opportunities in the direct embedding of fuel processing in polymer electrolyte membrane fuel cells through the internal thermal integration of exothermic electrochemical reactions with endothermic fuel reforming for hydrogen production. [ABSTRACT FROM AUTHOR]

Front Cover: Aqueous-Phase Selective Oxidation of Methane with Oxygen over Iron Salts and Pd/C in the Presence of Hydrogen (ChemCatChem 17/2019) Shows the catalyst system composed of homogeneous iron salt and heterogeneous Pd/C which are responsible for aqueous-phase methane oxidation with oxygen in the presence of hydrogen even at low temperatures near 0 °C. When hydrogen peroxide was directly added, the turnover frequency (TOF), defined as the moles of methane oxygenates per moles of Fe per unit time, at 293 K was 29 h SP -1 sp at pH = 2.3. [Extracted from the article]