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Controlling the selectivity in single-step conversion of syngas to single aromatic hydrocarbon to enhance CO utilization is a big challenge. By adapting the reaction coupling methodology, which allows the precise control of C–C coupling reaction, we obtained a high selectivity of ∼70% of a single product, tetramethylbenzene (TeMB), in hydrocarbons, at total CO conversion of 37%. This was enabled by the reaction of H2-deficient syngas over a composite catalyst of physically mixed nanosized ZnCr2O4 and H-ZSM-5. The H-ZSM-5 employed in this work appeared as a coffin shape with short straight channels [010] along the b-axis that exhibit low molecular-diffusion resistance, resulting in high selectivity of aromatics, particularly TeMB. Due to selective methanol formation and enhanced molecular diffusion, we observed an aromatic vacancy created inside H-ZSM-5 pores, which boosts the transformation of olefins into aromatics, thus making the aromatic cycle dominant in a dual-cycle mechanism and giving a high yield of aromatics and TeMB. Furthermore, no catalyst deactivation was observed within 600 h of reaction time using H2-deficient syngas. Therefore, by rejecting the need for extra H2 addition into the syngas-to-aromatics (STA) reaction system, direct conversion of H2-deficient syngas derived from coal/biomass into TeMB makes an attractive industrial process.

Identifying the atomic structures of porous materials in spatial and temporal dimensions by (scanning) transmission electron microscope ((S)TEM) is significant for their wide applications in catalysis, separation and energy storage. However, the sensitivity of materials to electron beams made it difficult to reduce the electron damage to specimens while maintaining the resolution and signal‐to‐noise ratio. It is therefore still challenging to capture multiple images of the same area in one crystal to image the temporal changes of lattices. Usings integrated differential phase contrast (iDPC) STEM, atomic‐resolution imaging of beam‐sensitive zeolite frameworks is achieved with an ultralow dose of 40 e− Å−2, 2–3 orders of magnitude lower than that of conventional STEM. Based on the iDPC technique, not only the atomic 3D architecture of ZSM‐5 crystals but also the changes of frameworks are observed during in situ experiments. Local structures and light‐element aromatics in ZSM‐5 crystals can also be revealed directly under iDPC‐STEM. These results provided not only an efficient tool to image beam‐sensitive materials with ultralow beam current but also a new strategy to observe and investigate the hydrocarbon pools in zeolite catalysts at the single‐molecule scale.

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