Publications by authors named "Quanzheng Deng"

Quasicrystals, characterized by long-range order and the absence of translational symmetry, have attracted great attention due to their extraordinary physicochemical properties. Although quasicrystals have been discovered in various experimental systems, the formation mechanisms that yield quasicrystals at the mesostructural scale remain elusive. Herein, a unique formation pathway of dodecagonal quasicrystal in silica mesoporous crystals is reported, employing cationic surfactant as a soft template and organosilane as a co-structure directing agent.

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Unraveling the mechanism of zeolite crystallization, especially in a complex system containing dual-template agents, remains a critical challenge. In this work, we introduced, for the first time, novel operando two-dimensional (2D) solid-state NMR spectroscopy under extreme conditions of high temperature and high pressure, allowing for observations with atomic-level spatial and temporal resolution, thereby enabling unprecedented insights into the crystallization of SAPO-34 zeolite. By utilizing operando 2D P{H} HETCOR, Al{H} HMQC NMR techniques, we clarified the intricate cooperative and competitive interactions of dual-template agents and highlighted the synergistic effect between templates and hydroxyl groups during CHA zeolite crystallization.

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Zeolitic nanosheets possess great potential in catalysis due to their enhanced transport property and accessibility toward bulky molecules compared to conventional micron- meter scale crystals. However, the generation of Beta zeolite nanosheets, which are crucial for industrial catalysis, is still challenging for its intergrowth nature. In this work, aluminosilicate Beta nanosheets of ca.

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New symmetries of the gyroid (G) surfaces are the key to their intriguing properties. Here, we present a protocol to create a tetragonal gyroid substructure (shifted tG) outside the traditional cubic symmetry of G surfaces. We describe steps for employing a binary self-assembly system consisting of block copolymers and surfactants.

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D-amino acids, found in excess in a minority of organisms and crucial for marine invertebrates, contrast with the more common L-amino acids in most life forms. The local prebiotic origin of D-amino acid enantiomeric excess in natural systems remains an unsolved conundrum. Herein, we demonstrate the formation of enantiomeric excess (ee) D-amino acids through photocatalytic reductive amination of α-keto acids on natural pyrite.

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As one of the most stunning biological nanostructures, the single-diamond (SD) surface discovered in beetles and weevils exoskeletons possesses the widest complete photonic bandgap known to date and is renowned as the "holy grail" of photonic materials. However, the synthesis of SD is difficult due to its thermodynamical instability compared to the energetically favoured bicontinuous double diamond and other easily formed lattices; thus, the artificial fabrication of SD has long been a formidable challenge. Herein, we report a bottom-up approach to fabricate SD titania networks via a one-pot cooperative assembly scenario employing the diblock copolymer poly(ethylene oxide)--polystyrene as a soft template and titanium diisopropoxide bis(acetylacetonate) as an inorganic precursor in a mixed solvent, in which the SD scaffold was obtained by kinetically controlled nucleation and growth in the skeletal channels of the diamond minimal surface formed by the polymer matrix.

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A high-silica zeolite ECNU-13 (Si/Al=23) with a new three-dimensional (3D) pore system and a nanosized morphology has been developed, consisting of multitudes of 10-membered ring (10-R) medium pores and one set of 8-R small pores. A phase-discrimination strategy was proposed to synthesize ECNU-13 by regulating the gel compositions and nucleation processes that were used for preparing 12-R large-pore germanosilicate IM-20 with the known UWY topology. The crystallization was directed towards forming one set of single four-ring (s4r) composite building units together with one set of double four-ring (d4r) rather than two different types of d4r units in IM-20.

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Achieving strong and broadband circularly polarized colour responses in chiral inorganic materials is challenging. Here, we fabricated chiral mesostructured bismuth oxybromide (BiOBr) films (CMBFs) via hydrothermal growth using chiral sugar alcohols as symmetry-breaking agents. The layered slabs of BiOBr crystals with weak van-der-Waals interactions are prone to mismatching due to the chiral driving force, resulting in hierarchically chiral arrangements of fine size.

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Controlling crystal size and shape of zeolitic materials is an effective way to promote their mass transport and catalytic properties. Herein, we report a single step, Na - and porogen- free crystallization of MFI hierarchical architecture made up of aligned nanocrystals with reduced b-axis thickness (5-23 nm) and adjustable Si/Al ratios between 35 to 120, employing the commonly used tetrapropylammonium hydroxide (TPAOH) and tetrabutylammonium hydroxide (TBAOH) as structure-directing agents (SDAs). Homogeneous nucleation driven by both SDAs and subsequent SDA-exchange induced dissolution-recrystallization are responsible for the formation of such structure.

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