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Amorphous carbon holds great promise as anode material for sodium‐ion batteries due to its cost‐effectiveness and good performance. However, its sodium storage mechanism, particularly the insertion process and origin of plateau capacity, remains controversial. Here, an extended adsorption/insertion‐filling sodium storage mechanism is proposed using petroleum coke‐derived amorphous carbon as a multi‐microcrystalline model. Combining in situ X‐ray diffraction, in situ Raman, theoretical calculations, and neutron scattering, the effective storage form and location of sodium ions in amorphous carbon are revealed. The sodium adsorption at defect sites leads to a high‐potential sloping capacity. The sodium insertion process occurs in both the pseudo‐graphite phase (d002 > 0.370 nm) and graphite‐like phase (0.345 ≤ d002 < 0.370 nm) rather than the graphite phase, contributing to low‐potential sloping capacity. The sodium filling into accessible closed pores forms quasi‐metallic sodium clusters, contributing to plateau capacity. The threshold of the effective interlayer spacing for sodium insertion is extended to 0.345 nm, breaking the consensus of insertion interlayer threshold and enhancing understanding of closed pore filling. The extended adsorption/insertion‐filling mechanism explains the sodium storage behavior of amorphous carbon with different microstructures, providing theoretical guidance for the rational design of high‐performance amorphous carbon anodes. [ABSTRACT FROM AUTHOR]

Removal of confined space carbon dioxide (CO2) that is in low concentration and with coexisting water is necessary but challenging by physical adsorption method. To make the removal process effective, rendering the nanopore surface hydrophobic to resist water is the popular way. Instead of preventing water from occupying the nanopores, in this work, we propose to utilize the guest water for the spatially selective formation of local surface bound water and further induce the preferential CO2 capture. We observe an anomalous enhancement of CO2 capture performance under humid conditions over carbon nanopores with spatially selective polar sites. It is evidenced that the surface bound water is formed at non-CO2-selective areas of polar carbon nanopores, thus creating additional CO2 trapping sites. This work may inspire the design of environment tolerable materials for molecular separation and purification under harsh conditions. The removal of low-concentration humid CO2 from confined space is necessary but challenging. Here, the authors propose a strategy to boost the humid CO2 removal performance by dynamically optimizing polar carbon nanopores with the formation of local surface bound water. [ABSTRACT FROM AUTHOR]

Separation of hydrogen isotopes (D2/H2) attracts wide interest due to its important applications, such as nuclear fusion. Kinetic quantum sieving‐induced separation over tailored nanoporous solids is a promising method; however, the dynamic separation often shows a transient feature, thus a low D2/H2 selectivity even at temperature below 50 K. Herein, we selectively enriched the accessible quantum sieving (AQS) sites in two‐dimensional carbons by chemically growing a pore‐narrowing layer. The spatial density of such AQS sites is 8.5 times higher than that of commercial carbon molecular sieves. The kinetic selectivity of D2/H2 reached 4.6 at 77 K. Column breakthrough experiments revealed that the dynamic D2/H2 separation was enhanced by such a nanopore design. Aspen simulation indicated that D2 was enriched to 93.1% within 11 pressure swing adsorption cycles with a 1% D2/99% H2 mixture as feed. [ABSTRACT FROM AUTHOR]

Selective separation of industrial important C8, C6 and C3 hydrocarbon pairs by physisorbents can greatly reduce the energy intensity related to the currently used cryogenic distillation techniques. The achievement of size‐sieving based on carbonaceous materials is desirable, but commonly hindered by the random structure of carbons often with a broad pore size distribution. Herein, a pH‐regulated pre‐condensation strategy was introduced to control the carbon pore architecture by the sp2/sp3 hybridization of precursor. The lower pH value during pre‐condensation of glucose facilitates the growth of aromatic nanodomains, rearrangement of stacked layers and a concomitant transition from sp3‐C to sp2‐C. The subsequent pyrolysis endows the pore size manipulated from 6.8 to 4.8 Å and narrowly distributed over a range of 0.2 Å. The refined pores enable effective size‐sieving of C8, C6 and C3 hydrocarbon pairs with high separation factor of 1.9 and 4.9 for C8 xylene (X) isomers para‐X/meta‐X and para‐X/ortho‐X, respectively, 5.1 for C6 alkane isomers n‐hexane/3‐methylpentane, and 22.0 for C3H6/C3H8. The excellent separation performance based‐on size exclusion effect is validated by static adsorption isotherms and dynamic breakthrough experiments. This synthesis strategy provides a means of exploring advanced carbonaceous materials with controlled hybridized structure and pore sizes for challenging separation needs. [ABSTRACT FROM AUTHOR]

Ethylene glycol is a useful organic compound and chemical intermediate for manufacturing various commodity chemicals of industrial importance. Nevertheless, the production of ethylene glycol in a green and safe manner is still a long‐standing challenge. Here, we established an integrated, efficient pathway for oxidizing ethylene into ethylene glycol. Mesoporous carbon catalyst produces H2O2, and titanium silicalite‐1 catalyst would subsequently oxidize ethylene into ethylene glycol with the in situ generated H2O2. This tandem route presents a remarkable activity, i.e. 86 % H2O2 conversion with 99 % ethylene glycol selectivity and 51.48 mmol gecat−1 h−1 production rate at 0.4 V vs. reversible hydrogen electrode. Apart from generated H2O2 as an oxidant, there exists ⋅OOH intermediate which could omit the step of absorbing and dissociating H2O2 over titanium silicalite‐1, showing faster reaction kinetics compared to the ex situ one. This work not only provides a new idea for yielding ethylene glycol but also demonstrates the superior of in situ generated H2O2 in tandem route. [ABSTRACT FROM AUTHOR]