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Preventing the sintering of nano‐catalyst is crucial to maintain their performance especially for high‐temperature reactions such as CO2 reforming of methane (DRM) reaction. In this paper, we design CeO2 nanorod@Ni phyllosilicate (CeO2@NiPhy) catalysts with different NiPhy shell thickness to simultaneously preserve the morphology of CeO2 nanorod and prevent the sintering of Ni. Compared with Ni/CeO2 supported catalyst, CeO2@NiPhy core‐shell catalyst with a shell thickness of 9 nm exhibits much better performance for DRM with stable CH4 and CO2 conversions of 75 % and 80 % respectively and lower carbon deposition due to high Ni sintering resistance and higher thermal stability of CeO2 during calcination and DRM reaction thereby higher oxygen vacancies concentration. In‐situ diffuse reflectance infrared Fourier transform spectra result demonstrates that DRM reaction takes place with a bi‐functional mechanism on CeO2@NiPhy. This design strategy can be applied to prepare other nano‐catalysts with high sintering resistance of both active metal and catalyst support for high‐temperature applications. [ABSTRACT FROM AUTHOR]

Methane dry reforming (DRM) reaction is an efficient strategy to achieve carbon neutralization. Whereas, nano-catalysts, which are highly active due to size effect, are prone to sinter under the relatively high reaction temperature conditions, leading to the degradation of catalytic performance and accumulation of carbon. Therefore, preventing sintering is highly desired. In this manuscript, we synthesize cubic CeO 2 yolk Ni phyllosilicate shell (CeO 2 @Ni-Ps YS) catalyst which exhibits superb catalytic performance for DRM reaction. This is because the Ni bearing Ps structure mitigates the agglomeration of Ni nanoparticles due to strong metal support interaction (MSI); whilst CeO 2 still preserves cubic morphology due to the protection by yolk shell structure, isolating CeO 2 from each other. In addition, the yolk shell structure also provides intimate interaction between reactant gases and catalyst, which is known as confinement effect and further contributes to its better catalytic performance than the CeO 2 @Ni-Ps CS catalyst. By comparison, serious sintering of both Ni and CeO 2 occurs for DP Ni-Ps/CeO 2 catalyst, leading to its continuous degradation of DRM performance. This method is promising to synthesize other efficient yolk shell catalysts for use in sustainable reaction processes. [Display omitted] • CeO 2 @Ni-Ps YS catalyst is designed via hydrothermal and micro-emulsion method. • It shows outstanding sintering and carbon resistance for DRM reaction. • Strong MSI between Ni and Ni Ps phase prevents Ni sintering. • The yolk shell structure mitigates the sintering of cubic CeO 2. • The yolk shell catalyst has high concentration of oxygen vacancy. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • NiCo@NiCo phyllosilicate@CeO 2 core shell hollow spheres have been designed. • They exhibit active and stable performance of 45 h TOS for STR reaction. • High metal sintering resistance and oxygen vacancies alleviate the carbon deposition. • Synergistic effect between Ni and Co further improves their carbon resistance. • They show promising application in tar steaming reforming reaction. Abstract Developing sintering and carbon resistant tar removal catalysts is crucial for biomass gasification technology. Herein, for the first time, NiCo@NiCo phyllosilicate@CeO 2 hollow core shell catalysts have been designed for steam reforming of toluene (SRT) as the biomass tar model compound. They show both good catalytic activity and stability within 45 h of time on stream due to their high sintering resistance of NiCo because of the strong interactions between NiCo and CeO 2 , high metal exposure as a result of the high specific surface area, high surface metal concentration as well as the high oxygen vacancies as evidenced from the H 2 -Temperature-programmed reduction (H 2 -TPR), H 2 chemisorption and X-ray photoelectron spectroscopy (XPS) characterizations respectively. Additionally, the synergistic effect between Ni and Co further improves their carbon resistant property. By comparison, Co@Co phyllosilicate@CeO 2 catalysts perform the lowest toluene conversion and stability mainly due to their structural instability during reaction resulting from their high Si/Co ratio, leading to their low specific surface area and Co exposure. The outstanding SRT performance of NiCo@NiCo phyllosilicate@CeO 2 catalysts indicates their promising application for steam reforming of biomass tar reaction. [ABSTRACT FROM AUTHOR]

Abstract: A great challenge for cheap and active Ni‐based catalysts to be utilized for CO2 (dry) reforming of methane (DRM) reaction is their high‐carbon‐deposition problem. Herein, we designed multi‐Ni‐core@Ni phyllosilicate@CeO2 (Ni@NiPhy@CeO2) shell hollow sphere catalysts using a facile precipitation method. Compared with Ni@NiPhy without CeO2 shell, Ni@NiPhy@CeO2 exhibits high carbon resistance for the DRM reaction at both high GHSV value of 1880 L g−1 cat h−1 at 700 °C and a low reaction temperature of 600 °C. In addition, they show high and stable CH4 and CO2 conversions of 72.8 % and 79.1 % respectively at 700 °C under normal GHSV value of 36 L g−1 cat h−1. The good catalytic performance of Ni@NiPhy@CeO2 can be attributed to their high sintering resistance of both Ni and CeO2 which yields a high concentration of oxygen vacancies thereby a high catalytic performance and carbon resistance for DRM reaction. The facile synthesis method in this work can easily be applied to design other core–shell hollow catalysts such as Ni–M (M=Mg, Co, Cu, and Fe) silicate@CeO2 according to specific applications. [ABSTRACT FROM AUTHOR]

Abstract: A great challenge for cheap and active Ni‐based catalysts to be utilized for CO2 (dry) reforming of methane (DRM) reaction is their high‐carbon‐deposition problem. Herein, we designed multi‐Ni‐core@Ni phyllosilicate@CeO2 (Ni@NiPhy@CeO2) shell hollow sphere catalysts using a facile precipitation method. Compared with Ni@NiPhy without CeO2 shell, Ni@NiPhy@CeO2 exhibits high carbon resistance for the DRM reaction at both high GHSV value of 1880 L g−1 cat h−1 at 700 °C and a low reaction temperature of 600 °C. In addition, they show high and stable CH4 and CO2 conversions of 72.8 % and 79.1 % respectively at 700 °C under normal GHSV value of 36 L g−1 cat h−1. The good catalytic performance of Ni@NiPhy@CeO2 can be attributed to their high sintering resistance of both Ni and CeO2 which yields a high concentration of oxygen vacancies thereby a high catalytic performance and carbon resistance for DRM reaction. The facile synthesis method in this work can easily be applied to design other core–shell hollow catalysts such as Ni–M (M=Mg, Co, Cu, and Fe) silicate@CeO2 according to specific applications. [ABSTRACT FROM AUTHOR]

Ni@Ni-Mgphy(Ni-Mgphy = Ni–Mg phyllosilicate) core–shellcatalysts were designed by hydrothermally treating Ni@SiO2nanoparticles with magnesium nitrate salt. The porosity and basicityof the catalysts were easily tuned by forming Ni-Mgphy shell usingNi originating from Ni@SiO2during the hydrothermal treatmentprocess and Mg(NO3)2as the Ni and Mg sources,respectively. Among Ni@Ni-Mgphy core–shell catalysts synthesizedunder different hydrothermal durations, the catalyst treated for 10h achieved the best catalytic performance for CO2reformingof CH4reaction with stable CO2and CH4conversions of around 81% and 78%, respectively, within 95 h reactionduration at 700 °C. The high Ni accessibility, strong basicity,and high structural stability for Ni@Ni-Mgphy core–shell catalystwith 10 h treatment time accounted for its superb catalytic performance.This method to simultaneously tune the porosity and basicity of Ni@SiO2core–shell nanoparticles demonstrates a general wayto modify the properties of other silica based core–shell nanoparticlesthrough treating them with different metal salts. [ABSTRACT FROM AUTHOR]

CO 2 (dry) reforming of CH 4 (DRM) reaction is an attractive measure to not only mitigate the environmental problems such as global warming but also produce the syngas as feedstock for liquid fuel production. Great achievements have been made in various DRM processes such as thermally-driven DRM, plasma-assisted DRM and solar-driven DRM together with the corresponding catalyst design strategies. Herein, the merits and demerits of these three processes as well as these design strategies are compared and analyzed. We start with thermally-driven DRM which accounts for the large majority of researches being reported in the recent five years (2016–2020). Four typical measures to achieve sintering and carbon resistant catalysts including designing catalysts with strong MSI, bimetallic catalysts, layered doubled hydroxide catalysts and core shell structured catalysts are summarized. Thereafter, for plasma-assisted DRM, the effect of operating parameters to the performance of classical plasma reactors as well as the influence of different packing materials for these packed plasma reactors are analyzed. After this, for solar-driven DRM, the application and design of solar reactors are discussed for solar thermocatalysis, which is followed by the discussion of solar photocatalysis and hybrid photothermo catalysis. Finally, we propose potential challenges and research directions of these three processes to give a comprehensive understanding of DRM reaction. Image 1 • CH 4 dry reforming-DRM is attractive to mitigate global warming and produce syngas. • Sintering/carbon resistant catalyst design is imperative for thermally-driven DRM. • Catalyst design strategies featured for plasma-assisted DRM are highly desired. • Light management and solar reactor engineering are challenging for solar-driven DRM. • Understanding in situ generated reactive species during DRM reaction is vital. [ABSTRACT FROM AUTHOR]

CH x * oxidation is one of the most vital routes to alleviate the carbon deposition problem of CO 2 reforming of methane (DRM) reaction. Whereas, little experimental evidence has been observed on NiMo catalysts where the CH x * oxidation was dominant over its dissociation reaction. Herein, to experimentally unveil the CH x * oxidation route of NiMo catalysts, we design three catalysts with different particle sizes and structures. Among them, Mo/Niphy@SiO 2 core shell catalyst demonstrated the dominant CH x * oxidation route over its dissociation based on in-situ diffuse reflectance infrared Fourier transform spectroscopy experiments. This was attributed to the confinement effect of SiO 2 and the formation of Ni–Mo alloy, inhibiting the CH x * dissociation reaction. It exhibited relatively stable CH 4 and CO 2 conversions (77 % and 75 % respectively) within 180 h. By contrast, on Mo/Niphy catalyst which has a big Ni size, CH x * was mainly dissociated to C* and oxidized to CO which further underwent a disproportion reaction to produce CO 2 and C*, leading to the severe carbon deposition and unstable DRM performance. The strategy to unveil the dominant role of CH x * oxidation via design catalysts with different sizes and structures sheds light on the study of reaction mechanism of other reactions. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • DRM and CRR are valuable for carbon neutralization and syngas production. • Catalyst design strategies are crucial to improve CO 2 utilization efficiency. • Structured catalysts design are effective in decreasing carbon deposition for DRM. • Electronic structure, size, morphology, and porosity tuning are efficient for CRR. • Mechanism understanding using in situ characterization tools is important. CO 2 conversion to produce syngas via reforming of CH 4 and electrochemical reduction reaction is attractive to achieve carbon neutralization, mitigate CO 2 related environmental problems, and provide important intermediate for value-added chemicals production. Tremendous progress has been made in the catalyst development for these two reactions, which is critical to improve the utilization efficiency of the inert CO 2. Whereas, catalyst design strategies for these two reactions have not been systematically discussed. Therefore, here, design strategies such as increasing sintering resistance, enhancing redox property, basicity, and porosity etc. for structured catalysts including core/yolk shell, perovskite and spinel catalyst for DRM are analysed. In addition, CRR catalyst design measures from both atomic-, molecular- and meso -scale for instance tuning of electronic structure, size, morphology, and porosity to increase the syngas selectivity are compared. Finally, challenges and future work of these two reactions are proposed. Some of the challenges and solutions include (1) facile large scale synthesis strategies are highly desired to design multifunctional catalysts with low mass transfer resistance in addition to silica-based and noble-metal based catalysts; (2) mechanism illustration of confinement effect, synergistic effect, and intermediate species are crucial and feasible aided with various in situ characterization techniques; (3) more stringent reaction conditions are required to boost their industrial process of these two reactions. This review is timely and useful to boost the advancement of these two reactions and promote carbon neutralization. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnZrO x /ZSM-5@t-ZrO 2 is designed for enhanced CO 2 hydrogenation to C 2 =–C 4 =. • T-ZrO 2 coating ZSM-5 is the key to improve the selectivity of C 2 =–C 4 =. • The t-ZrO 2 neutralizes the strong Brønsted acid sites of ZSM-5. • The t-ZrO 2 inhibitis excessive hydrogenation of C 2 =–C 4 =. • ZnZrO x /ZSM-5@t-ZrO 2 generated 81.1% of C 2 =–C 4 = and the byproduct CO is only 34.3%. The hydrogenation of carbon dioxide to light olefins is a direct and effective approach for achieving carbon neutrality. However, developing a tandem catalytic process involving methanol as an intermediate to achieve efficient directional conversion under mild conditions remains a challenge. Thus, we designed and constructed a bifunctional tandem catalyst, ZnZrO x /ZSM-5@n-ZrO 2 , where n represents the amorphous (am), monoclinic (m), and tetragonal (t) phases of ZrO 2. The catalyst was prepared by coating an n-ZrO 2 layer on the surface of ZSM-5 zeolite to form ZSM-5@n-ZrO 2 with a coating structure, which was then ground and mixed with ZnZrO x to obtain the ZnZrO x /ZSM-5@n-ZrO 2 tandem catalyst. At 340 °C and 2 MPa, the selectivity of the ZnZrO x /ZSM-5@t-ZrO 2 catalyst toward light olefins reached 81.1%, with the carbon monoxide (CO) byproduct constituting only 34.3%. In contrast, the selectivity of ZnZrO x /ZSM-5 catalyst toward light olefins reached only 40.5% and a CO selectivity of 56.8%. Various characterizations and experimental results indicate that the ZSM-5@t-ZrO 2 coating structure in the designed bifunctional catalyst effectively regulates the acid density and pore distribution of zeolite while inhibiting excessive hydrogenation of light olefins, ultimately achieving the desired mild transformation. [ABSTRACT FROM AUTHOR]

• The hybrid DBD plasma-catalysis system is promising for RWGS at low temperature. • LSNFO shows the highest potential in promoting the selective conversion of CO 2 to CO. • The Ni-Fe alloy and oxygen vacancies in LSNFO contribute to its superior performance. • A H 2 /CO 2 ratio of 2:1 is the most promising with the highest CO yield of 56 %. With the aim of eliminating the serious environmental concern arising from excessive anthropogenic CO 2 emission, a hybrid dielectric barrier discharge plasma-catalysis system was developed for the thermodynamic unfavorable reverse water-gas shift reaction at low temperature of < 150 °C. A series of perovskite catalysts including LaNiO 3 , La 0.9 Sr 0.1 NiO 3+ δ, La 0.9 Sr 0.1 FeO 3+ δ and La 0.9 Sr 0.1 Ni 0.5 Fe 0.5 O 3+ δ were synthesized, as well as the impregnated Ni/La 2 O 3 as a reference. Among, La 0.9 Sr 0.1 Ni 0.5 Fe 0.5 O 3+ δ exhibited the highest potential in promoting the selective conversion of CO 2 to CO, and simultaneously suppressing the formation of CH 4. Its superior catalytic performance should be attributed to that (1) higher metal dispersion, smaller particle size, stronger metal-support interaction and electronically richer state of Ni were achieved by the formation of Ni-Fe alloy, which facilitated the adsorption and conversion of CO 2 , and (2) more oxygen vacancies and higher oxygen mobility were created by the remaining La 0.9 Sr 0.1 FeO 3+ δ perovskite structure, which promoted the selective conversion of CO 2 to CO. [ABSTRACT FROM AUTHOR]

Review: 146 refs. [ABSTRACT FROM AUTHOR]