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As a primary constituent of natural gas and shale gas, direct conversion of methane has attracted significant attention due to its potential to reduce energy consumption and CO2 emissions. Compared with thermal catalysis, photocatalysis has the capacity to transcend thermodynamic constraint and enable the conversion of sustainable solar energy into chemical energy under mild reaction condition, which contributes to optimize the utilization of methane. In this review, we undertake a comparative analysis of various strategies for photocatalytic methane conversion to syngas and chemicals, including photocatalytic reforming of methane, photocatalytic partial oxidation of methane and photocatalytic coupling of methane. The distinct reaction systems with corresponding catalysts and underlying mechanisms are expounded in detail to foster a profound comprehension of solar‐driven methane conversion. Finally, the challenges and prospectives in photocatalytic methane conversion are discussed. [ABSTRACT FROM AUTHOR]

Photocatalytic methane oxidation to oxygenates with promising performance remains as a grand challenge due to the low productivity and severe overoxidation. Herein, SrWO4/TiO2 heterojunction was developed for photocatalytic methane oxidation with O2 to liquid oxygenates (Please replace "oxygenates" with "oxygenated")products under mild reaction conditions. The optimized SrWO4/TiO2 catalyst exhibited high productivity of 13365 μmol/g with high selectivity of 98.7 % for oxygenates. Benefited from the intimate heterojunction interface of SrWO4/TiO2, the constructed I‐type heterostructure improved the separation and transfer of photogenerated carriers, and a high‐speed transfer channel for photogenerated carriers was fabricated. Simultaneously, the special band structure can increase the amount of photogenerated electrons and holes on the TiO2 surface, which promoted the formation of reactive oxygen species to enhance liquid oxygenates productivity. [ABSTRACT FROM AUTHOR]

As a clean fossil energy and chemical feedstock, development of breakthrough strategies for direct conversion of methane (CH4) into various chemicals under mild reaction conditions is highly desired. Herein, Rh/ZSM‐5 catalyst was reported to convert CH4 to oxygenates with molecular oxygen (O2) in the presence of CO at low temperature with promising catalytic performance. The oxygenates productivity reached as high as 5638.0 μmol gcat.−1 h−1. Structure characterization confirmed the existence of highly dispersed Rh2O3 nanoparticles with an average diameter of 2.4 nm in the Rh/ZSM‐5 catalyst. Based on control experiments and mechanism study, it was suggested that CO plays a pivotal role over the Rh/ZSM‐5 catalyst to boost direct oxidation of methane. CO participates in water‐gas‐shift reaction to produce in‐situ H species, which enables to form *OH, *OOH and H2O2 active species by reacting with O2. The as‐obtained *OH, *OOH and H2O2 species will thus render high activity for methane oxidation. [ABSTRACT FROM AUTHOR]

Selective oxidation of methane to oxygenates using low‐cost and environment‐friendly molecular oxygen (O2) under mild reaction conditions is a promising strategy but still remains grand challenge. It is of great importance to accelerate the activation of O2 to generate highly active oxygen species, such as hydroxyl peroxide and hydroxyl species to improve catalytic performance for selective oxidation of methane. Selective oxidation of methane using O2 by coupling with in situ generation of hydrogen peroxide via tandem catalysis ensures the easy formation of active oxygen species for methane activation, leading to high oxygenates productivity under mild conditions. In this concept, we summarized the recent progresses for selective oxidation of methane to oxygenates using O2 based on tandem catalysis by coupling with in situ generation of hydrogen peroxide. The remaining challenges and future perspectives for selective oxidation of methane to oxygenates via tandem catalysis were also proposed. [ABSTRACT FROM AUTHOR]

The concept of green carbon science is to promote the goal of achieving carbon neutrality, the importance and urgency of which have been well‐recognized and received worldwide attention. Carbon neutrality has become the focus of research work in many fields, and correspondingly, a growing number of papers and publications have been published over the last few years. However, since carbon neutralization is a real problem that urgently requires technical solutions, the transition from fundamental research to practical applications must be accelerated. A number of research teams are bold in putting things into practice and blazing new trails. This Review summarizes the recent technological developments within the framework of green carbon science, focusing on conducted pilot tests, industrial demonstrations, and commercial applications beyond the laboratory stage. [ABSTRACT FROM AUTHOR]

Highly selective conversion of methane to oxygenates with O2 as a green oxidant remains a great challenge. It is still difficult to suppress the generation of COx (x=1, 2) as undesired by‐products due to unavoidable overoxidation reaction. Hence, tungsten‐doped (W‐doped) TiO2 photocatalysts were designed with a tunable band structure for photocatalytic oxidation of methane to C1 oxygenates using O2 at low temperature (30 °C). The W‐doping effectively modified the electronic and band structure of pristine TiO2 to enhance photocatalytic performance. Liquid oxygenates productivity could reach as high as 12.2 mmol g−1 with high selectivity of 99.4 %. Moreover, COx selectivity was effectively decreased from 21.2 % over TiO2 to 0.6 % for W‐doped catalyst. Detailed characterizations further disclosed that W‐doping not only enhanced light absorption, but also promoted the separation of photo‐generated carriers to improve methane conversion. This work provides new insights into the design of highly efficient photocatalysts for methane oxidation. [ABSTRACT FROM AUTHOR]

Selective oxidation of methane to oxygenates with O2 under mild conditions remains a great challenge. Here we report a ZSM‐5 (Z‐5) supported PdCu bimetallic catalyst (PdCu/Z‐5) for methane conversion to oxygenates by reacting with O2 in the presence of H2 at low temperature (120 °C). Benefiting from the co‐existence of PdO nanoparticles and Cu single atoms via tandem catalysis, the PdCu/Z‐5 catalyst exhibited a high oxygenates yield of 1178 mmol g−1Pd h−1 (mmol of oxygenates per gram Pd per hour) and at the same time high oxygenates selectivity of up to 95 %. Control experiments and mechanistic studies revealed that PdO nanoparticles promoted the in situ generation of H2O2 from O2 and H2, while Cu single atoms not only accelerated the activation of H2O2 for the generation of abundant hydroxyl radicals (⋅OH) from H2O2 decomposition, but also enabled the homolytic cleavage of CH4 by ⋅OH to methyl radicals (⋅CH3). Subsequently, the ⋅OH reacted quickly with the ⋅CH3 to form CH3OH with high selectivity. [ABSTRACT FROM AUTHOR]

Gamma‐ray (γ‐ray) irradiation was introduced into zeolite synthesis. The crystallization process of zeolite NaA, NaY, Silicalite‐1, and ZSM‐5 were greatly accelerated. The crystallization time of NaA zeolite was significantly decreased to 18 h under γ‐ray irradiation at 20 °C, while more than 102 h was needed for the conventional process. Unexpectedly, more mesopores were created during this process, and thus the adsorption capacity of CO2 increased by 6‐fold compared to the NaA prepared without γ‐ray irradiation. Solid experimental evidence and density function theory (DFT) calculations demonstrated that hydroxyl free radicals (OH*) generated by γ‐rays accelerated the crystallization of zeolite NaA. Besides NaA, mesoporous ZSM‐5 with MFI topology was also successfully synthesized under γ‐ray irradiation, which possessed excellent catalytic performance for methanol conversion, suggesting the universality of this new synthetic strategy for various zeolites. [ABSTRACT FROM AUTHOR]

Cobalt carbide (Co2C) exhibits strong facet effect for Fischer‐Tropsch to olefins (FTO) reaction. Herein, we report that the facet proportion of Co2C nanostructures can be tuned effectively by incorporating and altering the Mn content in the CoMn composite oxide as catalyst precursor. With the addition of Mn promoter, the Co2C nanoprisms with exposed (020) and (101) facets are generated under reaction conditions. In addition, the facet proportion of Co2C(020) facet can be effectively improved by enhancing the Mn/Co ratio. With the increase of facet proportion of Co2C(020)/Co2C(101) ratio, the as‐obtained Co2C nanoprisms exhibit higher intrinsic activity and lower methane selectivity during the syngas conversion process. Kinetic experiments also demonstrate that the apparent activation energy (Ea) for CO conversion is significantly reduced as increasing the facet proportion of Co2C(020). This work provides a simple and feasible way to tune the exposed facet proportion for the rational design of Co2C nanocatalyst for FTO reaction. [ABSTRACT FROM AUTHOR]

Because lower olefins (C2=–C4=) are important bulk petrochemicals, their direct production from CO2 hydrogenation is highly attractive. However, the selectivity towards C2=–C4= by the modified Fischer–Tropsch synthesis is restricted to 56.7 % with high undesired methane selectivity. Here, a series of bifunctional catalysts containing In2O3‐ZnZrOx oxides and various SAPO‐34 zeolites with different crystal sizes (0.4–1.5 μm) and pore structures was developed for the production of lower olefins by CO2 hydrogenation. The C2=–C4= selectivity reached as high as 85 % among all hydrocarbons with very low CH4 selectivity of only 1 % at a CO2 conversion of 17 %. This demonstrated that the small crystal size, hierarchical pore structure, and appropriate amount of Brønsted acid sites of SAPO‐34 endowed the bifunctional catalysts with high C2=–C4= selectivity. This work shows an efficient way for developing bifunctional catalysts for direct CO2 hydrogenation to lower olefins. [ABSTRACT FROM AUTHOR]

Selective synthesis of higher oxygenates (linear α‐alcohols and α‐aldehydes, C2+ OH) from syngas is highly attractive but remains challenging owing to the low C2+ OH selectivity and low catalytic stability. Herein we introduce a multifunctional catalyst composed of CoMn and CuZnAlZr oxides that dramatically increased the oxygenates selectivity to 58.1 wt %, where more than 92.0 wt % of the produced oxygenates are C2+ OH. Notably, the total selectivity to value‐added chemicals including oxygenates and olefins reached 80.6 wt % at CO conversion of 29.0 % with high stability. The appropriate component proximity can effectively suppress the formation of the undesired C1 products, and the selectively propulsion of reaction network by synergetic effect of different components contributes to the enhanced selectivity to higher oxygenates. This work provides an alternative strategy for the rational design of new catalysts for direct conversion of syngas into higher oxygenates with co‐production of olefins. A stable multifunctional catalyst composed of CoMn oxides and CuZnAlZr oxides was developed for direct conversion of syngas to higher oxygenates and olefins with a total selectivity of 80.6 wt % at a CO conversion of 29.0 %. The interaction manner of the two components plays a crucial role in suppressing C1 products formation and enhancing the selectivity to higher oxygenates. [ABSTRACT FROM AUTHOR]

A series of Co/ SiO2 catalysts with different sodium (Na) loadings (0, 0.1, 0.2, 0.5 and 1 wt%) were prepared and evaluated for Fischer-Tropsch reaction to study the effect of Na on the catalyst structure and catalytic performance. The addition of Na was found to decrease the catalytic activity and hydrocarbon selectivity, but increase CO2 selectivity due to the enhanced WGS activity. The addition of Na also resulted in higher selectivity to oxygenates (alcohols and aldehydes) and O/P ratio as well as the shift of hydrocarbons to lower carbon numbers. Structure characterization revealed a decrease in the surface area and particles size for the calcined samples with the addition of Na. Co2C was formed during the reaction process for the Na-promoted catalysts. As a result, a new Co/ Co2C bifunctional active sites were generated for oxygenates formation leading to increasing oxygenates selectivity. In addition, the Co2C nanoparticles alone may also act as dual active sites for oxygenate formation at high reaction pressure over the promoted catalysts with high Na loading. [ABSTRACT FROM AUTHOR]

Three MFI parent zeolites with different morphological properties by different synthesis method were adopted. Alkaline treatment using sodium hydroxide was introduced to modify the structure of MFI zeolites. After iron exchange, the catalytic performance of both parent and modified MFI zeolites were evaluated in the N2O decomposition. The physicochemical properties were systematically characterized with various technologies, such as N2 adsorption-desorption, ICP, XRD, UV-Vis, 27Al MAS-NMR, TEM. The experiment results prove that the Fe-modified MFI catalysts with alkaline pre-treatment show much better catalytic activity than Fe-exchanged parent MFI catalysts. The curves of catalytic activities could move to low temperature range by 50-100 °C. Furthermore, in the presence of NO, the performance gap between Fe-Seed-M, Fe-Solid-M, and Fe-Com-M three samples is obviously reduced. Amongst, for the Fe-Solid-M sample synthesized by the solvent-free method, 90% N2O conversion could be attained at 500 °C, which shows potential to be applied the real condition. It is believed the hierarchical properties and the removal of amorphous substance is beneficial to the diffusion of ion exchange process. Therefore, the increase of active iron sites contributes to the improvement of catalytic performance. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

The synthesis of methanethiol from CS2 catalyzed by Ni-, Co-, or K-modified MoS2/SiO2 through the sequence CS2→CH3SH→CH3SCH3 (DMS) has been studied. CS2 is readily hydrogenated to CH3SH, whereas CH3SH and DMS decompose to CH4 at high CS2 conversions and temperatures. Thus, very high yields of CH3SH can be obtained on all the catalysts. The addition of Co or Ni accelerates all reaction steps to allow the formation of CH3SH under relatively mild conditions. On the contrary, K suppresses the formation of byproducts but also lowers the activity. The surface reaction proceeds through a series of hydrogen-addition steps, the rate-controlling step of which is the addition of the first H atom. H2 adsorbs dissociatively, whereas CS2 adsorbs strongly in a single active site prior to hydrogenation. The addition of Ni has a stronger enhancing effect on hydrogenation and accelerates the CS bond cleavage to a smaller extent than Co. Therefore, Ni leads to optimum CH3SH yields and holds the best promise as promoter for the MoS2 phase in the synthesis of methanethiol from CS2. [ABSTRACT FROM AUTHOR]

Strong metal‐support interactions (SMSI) featuring the formation of encapsulation overlayer around metal nanoparticles has drawn much attention in heterogeneous catalysis. Recent years, various novel SMSI phenomena have been observed and the nature of SMSI also has been revealed with the improvement of characterization techniques. Understanding the SMSI effect could deepen the insight into the structure‐activity relationship of metal‐supported catalysts, and rationally guide the design of special metal‐interface sites to manipulate catalytic behavior in chemical reaction. In this review, the research progress of SMSI and its application in heterogeneous COx hydrogenation are briefly surveyed, with emphasis on the advanced characterization, manipulation strategy and specific role of SMSI in Fischer‐Tropsch synthesis process, CO2 methanation and Reverse Water Gas Shift reaction. The current challenges and perspectives for the development of SMSI are also discussed. [ABSTRACT FROM AUTHOR]

MolybdENum carries the load The cover picture shows the reaction of CS2 and H2 over supported MoS2 ‐ type catalysts as a novel route for the synthesis of methanethiol, an important raw material in chemical industry. In their Full Paper on page   3249   ff., J.   A. Lercher and co ‐ workers describe the mechanism and kinetics of the reaction emphasizing the effect of Ni, Co, or K on the rates of hydrogENation and CS bond cleavage on MoS2. Thus, while aiming for the production of methanethiol with high rates and selectivity, the study also contributes to the understanding of the promotion of MoS2. [ABSTRACT FROM AUTHOR]