The study reports the first attempt to address the interplay between surface and bulk in hydride formation in ceria (CeO2) by combining experiment, using surface sensitive and bulk sensitive spectroscopic techniques on the two sample systems, i.e., CeO2(111) thin films and CeO2 powders, and theoretical calculations of CeO2(111) surfaces with oxygen vacancies (Ov) at the surface and in the bulk. We show that, on a stoichiometric CeO2(111) surface, H2 dissociates and forms surface hydroxyls (OH). On the pre‐reduced CeO2−x samples, both films and powders, hydroxyls and hydrides (Ce−H) are formed on the surface as well as in the bulk, accompanied by the Ce3+ ↔ Ce4+ redox reaction. As the Ov concentration increases, hydroxyl is destabilized and hydride becomes more stable. Surface hydroxyl is more stable than bulk hydroxyl, whereas bulk hydride is more stable than surface hydride. The surface hydride formation is the kinetically favorable process at relatively low temperatures, and the resulting surface hydride may diffuse into the bulk region and be stabilized therein. At higher temperatures, surface hydroxyls can react to produce water and create additional oxygen vacancies, increasing its concentration, which controls the H2/CeO2 interaction. The results demonstrate a large diversity of reaction pathways, which have to be taken into account for better understanding of reactivity of ceria‐based catalysts in a hydrogen‐rich atmosphere.

Crystal engineering is employed widely in developing metal-free room-temperature phosphorescence (RTP) materials, but the weak responsiveness in rigid state and poor selectivity during crystallization limit the research of RTP materials with specific recognition properties. Herein, based on multicomponent crystallization and the deformation of phosphor, we have developed a galactose-functionalized polyhydric compound (BHB) with a twisted 4-bromobiphenyl structure, to realize methanol selectively activated "off-on" RTP system. Methanol molecules selectively formed solvate with BHB and rigidified the crystal structure by enriching intermolecular noncovalent interactions. Meanwhile, the distortion of the biphenyl group facilitated the intersystem crossing process effectively, alongside the heavy-atom effect from the bromo substitute, thereby, activating the RTP of BHB. Thus our current research approach realizes RTP materials with selective recognition function by controlling multiple noncovalent interactions such as hydrogen and halogen bonding of molecular systems with structurally distorted phosphors.

The detailed information on the surface structure and binding sites of oxide nanomaterials is crucial to understand the adsorption and catalytic processes and thus the key to develop better materials for related applications. However, experimental methods to reveal this information remain scarce. Here we show that 17O solid-state nuclear magnetic resonance (NMR) spectroscopy can be used to identify specific surface sites active for CO2 adsorption on MgO nanosheets. Two 3-coordinated bare surface oxygen sites, resonating at 39 and 42 ppm, are observed, but only the latter is involved in CO2 adsorption. Double resonance NMR and density functional theory (DFT) calculations results prove that the difference between the two species is the close proximity to H, and CO2 does not bind to the oxygen ions with a shorter O···H distance of approx. 3.0 Å. Extensions of this approach to explore adsorption processes on other oxide materials can be readily envisaged.

The gasification reactivity of petroleum coke, which was treated by microwave at different times, powers, and temperatures, was investigated by using thermogravimetric analysis (TGA) at 1473 K at atmospheric pressure. The results showed that the gasification rate of petroleum coke increased with the increase of conversion and then decreased after reaching its maximum; the conversion corresponding to the maximal gasification rate is about x = 0.1. The gasification rate of petroleum coke increased with the increase of microwave irradiation time and irradiation power, but as the irradiation temperature increased, the gasification rate of petroleum coke first increased and then decreased. Petroleum coke before and after microwave treatment was analyzed by X-ray diffraction (XRD), infrared absorption spectroscopy (IR), and the accelerated surface area and porosimetry system (ASAP). The results showed that the crystalline structure of petroleum coke becomes amorphous and the BET surface area and pore volume become larger with increase of microwave irradiation time and irradiation power. As the irradiation temperature increased, the crystalline ordering degree of petroleum coke became weakened and then strengthened and the BET surface area and pore volume increased and then decreased, which agrees with the change in the petroleum coke gasification reaction rate. Results show that microwave treatment is an effective way to change the structure of petroleum coke and promote its gasification reactivity.

The hydrogen-borrowing amination of alcohols is a promising route to produce amines. In this study, experimental parameters involved in the preparation of Pt/CeO2 catalysts were varied to assess how physicochemical properties influence their performance in such reactions. An amination reaction between cyclopentanol and cyclopentylamine was used as the model reaction for this study. The Pt precursor used in the catalyst synthesis and the properties of the CeO2 support were both found to strongly influence catalytic performance. Aberration corrected scanning transmission electron microscopy revealed that the most active catalyst comprised linearly structured Pt species. The formation of these features, a function result of epitaxial Pt deposition along the CeO2 [100] plane, appeared to be dependent on the properties of the CeO2 support and the Pt precursor used. Density functional theory calculations subsequently confirmed that these sites were more effective for cyclopentanol dehydrogenationconsidered to be the rate-determining step of the processthan Pt clusters and nanoparticles. This study provides insights into the desirable catalytic properties required for hydrogen-borrowing amination but has relevance to other related fields. We consider that this study will provide a foundation for further study in this atom-efficient area of chemistry.