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Zeolites are among the most important heterogeneous catalysts, widely employed in separation reaction, fine chemical production, and petroleum refining. Through rational design of the frameworks, zeolites with versatile functions can be synthesized. Local imaging of zeolite structures at the atomic scale, including the basic framework atoms (Si, Al, and O) and extra-framework cations, is necessary to understand the structure–function relationship of zeolites. Herein, we implemented electron ptychography into direct imaging of local structures of two zeolites, Na-LTA and ZSM-5. Not only all the framework atoms but also extra-framework Na+ cations with only 1/4 occupation probabilities in Na-LTA were directly observed. Local structures of ZSM-5 zeolites having guest molecules among channels with different orientations were also unraveled using different reconstruction algorithms. The approach presented here provides a new way to locally image zeolites structure, and it is expected to be an essential key for further studying and tuning zeolites active sites at the atomic level., This work was supported by the Major State Basic Research Development Program of China (2022YFA1603703, 2022YFA1506000), the National Natural Science Foundation of China (21835002, 22222108, 92045303, 12027804, 21727817), the Shanghai Science and Technology Plan (21DZ2260400), the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB37040303), the Spanish National Research Council (CSIC) through the i-COOP program (COOPA20470), and CℏEM, School of Physical Science and Technology, ShanghaiTech University (#EM02161943). A.M. also thanks the Spanish Ministry of Science (RYC2018-024561-I), DGA (E13_20R), and European Union’s Horizon 2020 research and innovation program under grant agreement No. 823717-ESTEEM3.

Carbon nanomaterials, mainly carbon nanotubes (CNTs) and graphene, have received much attention in the past two decades. With the maturity of preparation technology and performance studies, they have been gradually applied in the industries of lithium-ion batteries (as conductive agents) and supercapacitors (as the main electrode materials). The large-scale production (up to thousands of tons per year) of CNTs has been realized, and the production cost has been greatly reduced. The production of graphene also exceeds one hundred tons per year, requiring the same improvement in performance/cost ratio. As one of the cheapest hydrocarbons, methane serves as a feedstock of both CNTs and graphene. The catalytic methane technology via the chemical vapor deposition method is advantageous for the controlled synthesis and mass production of carbon materials with high yield, high quality and at low cost, which are necessary requirements for any potential yet competitive commercial applications. Firstly, the methane deposition of CNTs is discussed, with a brief introduction on the preparation of CNTs, then the growth mechanism of CNTs, thermodynamics of methane decomposition in CNT synthesis, catalysts to decompose methane for CNT growth, and the synthesis of CNTs with different structures from methane. Secondly, the methane deposition of graphene is discussed, with a brief introduction on the preparation of graphene, then the growth kinetics of graphene, the quality estimation of graphene, and the synthesis of graphene with different structures from methane. Finally, the reactor technology for the enhanced production of CNTs and graphene is introduced, including the large-scale production of powder-like CNTs and graphene, ultralong CNTs, and graphene films, respectively. The review is useful for understanding the scientific and engineering challenges in this field and for the large-scale production of these important carbon nanomaterials from methane in the future.

A temperature-shifting two-stage fluidized bed reactor technology was used to convert propane and its intermediate products into aromatics. The first stage served for the aromatization of propane with a Ga/ZSM-5 catalyst at 570 °C. The second stage served for the alkylation of the intermediates of olefins at 300 °C. The increased yield of aromatics was attributed to the effective transformation of C2–C3 olefins as well as due to the suppression of the hydrogen transfer effect of the olefins.

There are a large number of zeolites, such as ITH, that cannot be prepared in the aluminosilicate form. Now, the successful synthesis of aluminosilicate ITH zeolite using a simple cationic oligomer as an organic template is presented. Key to the success is that the cationic oligomer has a strong complexation ability with aluminum species combined with a structural directing ability for the ITH structure similar to that of the conventional organic template. The aluminosilicate ITH zeolite has very high crystallinity, nanosheet-like crystal morphology, large surface area, fully four-coordinated Al species, and abundant acidic sites. Methanol-to-propylene (MTP) tests reveal that the Al-ITH zeolite shows much higher selectivity for propylene and longer lifetime than commercial ZSM-5. FCC tests show that Al-ITH zeolite is a good candidate as a shape-selective FCC additive for enhancing propylene and butylene selectivity., This work is supported by National Key Research and Development Program of China (2017YFB0702803), National Natural Science Foundation of China (21703203, 21673205, 21835002 and 21875140), Shanghai Pujiang Program (17PJ1406400), and the Young Elite Scientist Sponsorship Program by CAST (2017QNRC001). This work is partially supported by CħEM, SPST, ShanghaiTech (Grant 02161943), the Spanish Government‐MICINN through “Severo Ochoa” (SEV 2012‐0267) and RTI2018‐101033‐B‐I00, and the European Union through ERC‐AdG‐2014‐671093 (SynCatMatch). This work was also supported by INCOE program of BASF SE.

Cationic framework materials, especially pure inorganic cationic frameworks that can efficiently and selectively capture harmful heavy metal oxyanions from aqueous solution are highly desired yet scarcely reported. Herein, we report the discovery of a 2D cationic aluminum oxyhydroxide, JU-111, which sets a new benchmark for heavy metal oxyanion sorbents, especially for CrVI . Its structure was solved based on 3D electron diffraction tomography data. JU-111 shows fast sorption kinetics (ca. 20 min), high capture capacity (105.4 mg g-1 ), and broad working pH range (3-10) toward CrVI oxyanions. Unlike layered double hydroxides (LDHs), which are poorly selective in the presence of CO3 2- , JU-111 retains excellent selectivity for CrVI even under a large excess of CO3 2- . These superior features coupled with the ultra-low cost and environmentally benign nature make JU-111 a promising candidate for toxic metal oxyanion remediation as well as other potential applications.