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[Display omitted] • 3D spaced TiO 2 nanotube arrays (STNTs) were coated with ultra-fine metal nanocrystals. • We propose an absorption-diffusion regulation strategy to regulate Na deposition. • AIMD simulations demonstrate a mixed Na-Ag layer at the interface. • STNTs-Ag||Na displays a high Coulombic efficiency ∼99.5% even after 500 cycles. • STNTs-Ag-Na exhibits an ultralow overpotential of 4 mV and long cycling life over 1400 h. Sodium metal is considered as an excellent anode material for sodium-based energy storage devices with both high energy density and low cost, but the uncontrollable growth of sodium metal seriously limits its application. Herein, we firstly propose 3D spaced TiO 2 nanotube arrays (STNTs) uniformly coated with ultra-fine metal (Ag, Cu) nanocrystals as a substrate with absorption-diffusion regulation strategy to control the sodium metal deposition behavior. TiO 2 has a higher sodiophilic activity with larger Na absorption energy than the traditional copper substrate. Moreover, it is found by ab initio molecular dynamics (AIMD) simulations that it is much easier for Na to spread upon the surface of silver compared to copper, and thus forming a mixed Na-Ag layer at the interface. As a result, sodium metal is inclined to deposit inside or along the nanotube in STNTs-Ag in nanoscale. Finally, STNTs-Ag||Na half-cell displays a high Coulombic efficiency ∼99.5% even after 500 cycles with 1 mAh cm−2. Symmetric cell of STNTs-Ag-Na exhibits an ultralow overpotential of 4 mV and a long-term cycling life over 1400 h. Moreover, STNTs-Ag-Na anode coupling with Na 3 V 2 (PO 4) 3 cathode exhibits a significantly reduced polarization voltage with 22 mV and improved rate performance with 110 mAhg−1 at 10 C. [ABSTRACT FROM AUTHOR]

[Display omitted] • LTL-zeolite was used as a novel support for selective phenol hydrogenation. • LTL has one-dimensional large-pore diffusion system and adjustable base-acid sites. • Palladium nanoparticles were in-situ encapsulated within LTL-zeolite. • High Pd dispersions were obtained after encapsulation. • Switching chemical microenvironments around Pd sites changed the kinetic profiles. Cyclohexanone, as a significant raw material in the production of nylon 6 and nylon 66, is preferentially synthesized via selective phenol hydrogenation while the key point is to modulate the acidic/basic properties and metal dispersion of the catalytic system. Here, we report the fabrication of Pd@L core–shell catalysts via the in-situ encapsulation of Pd nanoparticles within the L zeolite with a one-dimensional large-pore diffusion system for the selective hydrogenation of phenol to cyclohexanone. The different Pd amounts and acidic/basic properties of the L zeolite catalyst were modulated to study the effects of the microenvironment around the Pd centers in the Pd@L on the catalytic performances of selective phenol hydrogenation. The results show that the basicity of L zeolite greatly favors high selectivity to cyclohexanone. In contrast, modulating the microenvironment to weak or strong acid states can result in the dehydration product forming on the acid sites or even the suppression of phenol hydrogenation. The conversion of phenol increases from 14.0% to 99.9% and meanwhile the selectivity of cyclohexanone ranges from 67.5% to 93.8%. In the optimum condition, the obtained Pd@KL catalyst can demonstrate excellent catalytic performance with the phenol conversion of 99.9% and the cyclohexanone selectivity of around 93.8%. Our work presents a promising tactic to effectively control the target reaction pathway by means of maneuvering the microenvironment in the proximity of metal nanoparticles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogenation of conjugated C = O is thermodynamically unfavored. • Highly dispersed Pt nanoparticles are well-embedded within S-1 microchannel. • Confinement effect of S-1 is employed to improve unsaturated alcohol selectivity. • C = O group is preferentially adsorbed on Pt@S-1 via on-top η 1 mode. • The on-top η 1 adsorption mode is more favored to C = O hydrogenation than d i -σ CO η 2. The issue for thermodynamically favored C = C hydrogenation needs to be overcome in the hydrogenation of ɑ, β-unsaturated aldehydes to unsaturated alcohols. Herein, we employ confinement effect in the catalyst-designing engineering to orient the C = O adsorption by the zeolitic microchannel, where highly dispersed Pt nanoparticles are homogeneously well-embedded within the silicalite-1 framework (Pt@S-1). Comprehensive characterizations, such as HAADF-STEM, H 2 -TPR, FT-IR of CO adsorption and XPS are carried out to demonstrate the geometric, confinement and electronic properties of metal species. In the hydrogenation of ɑ, β-unsaturated aldehydes with suitable molecular size, Pt@S-1 displays preferential C = O hydrogenation. For example, Pt@S-1 gives conversion of 99.8% and meanwhile the aiming cinnamal alcohol selectivity of 98.7% in the hydrogenation of cinnamaldehyde, outperforming larger Pt nanoparticles ill-suitedly embedded within silicalite-1 (Pt@S-1- is) and highly dispersed Pt nanoparticles supported on the silicalite-1 surface (Pt/S-1). For the hydrogenation of smaller 3-methyl-2-butenal, though the confinement effect boosts the C = O hydrogenation to some extent, the synergetic electronic effect via introducing Fe species effectively increases the unsaturated alcohol selectivity. Investigations on the adsorption configuration by in-situ FT-IR spectroscopy clearly indicate that the unsaturated aldehyde with suitable molecular size is preferentially adsorbed on Pt sites of Pt@S-1 via the oxygen atom of C = O with on-top η 1 mode, thus favoring high unsaturated alcohol selectivities, while the d i -σ CO η 2 and η 4 adsorption modes on Pt@S-1- is and Pt/S-1 are relatively adverse for prioritized C = O hydrogenation. [ABSTRACT FROM AUTHOR]