Competition among Refined Hollow Structures in Schiff Base Polymer Derived Carbon Microspheres

Synthetic polymer-derived hollow carbon spheres have great utilitarian value in many fields for which the synthesis of proper polymer precursors is a key process. The exploration of new suitable polymer precursors and the construction of refined hollow structures in emerging polymers are both of great significance for synthetic methodology and novel carbon materials. Here, for the first time Schiff base polymer (SBP) colloid spheres with refined hollow structures were synthesized by tandem gradient growth and confined polymerization processes. The Hill equation was employed as a mathematical model to explain the gradient growth of SBP spheres. The size-dependent inner structure of SBP spheres can be adjusted from hollow to multichamber-surrounded hollow, and then to a multichamber structure. SBP-derived carbon spheres having similar surface area and chemical composition but different inner structures provide an effective way to investigate the relationship between inner structure and performance.

Multidimensional Evolution of Carbon Structures Underpinned by Temperature-Induced Intermediate of Chloride for Sodium-Ion Batteries

Different dimensions of carbon materials with various features have captured numerous interests due to their applications on the tremendous fields. Restricted by the raw materials and devices, the controlling of their morphology is a major challenge. Utilizing the catalytic features of the intermediates from the low-cost salts and polymerization of 0D carbon quantum dots (CQDs), 0D CQDs are expected to self-assemble into 1/2/3D carbon structures with the assistance of temperature-induced intermediates (e.g., ZnO, Ni, and Cu) from the salts (ZnCl2, NiCl2, and CuCl). The formation mechanisms are illustrated as follows: 1) the "orient induction" to evoke "vine style" growth mechanism of ZnO; 2) the "dissolution-precipitation" of Ni; and 3) the "surface adsorption self-limited" of Cu. Subsequently, the degree of graphitization, interlayer distance, and special surface area are investigated in detail. 1D structure from 700 °C as anode displays a high Na-storage capacity of 301.2 mAh g-1 at 0.1 A g-1 after 200 cycles and 107 mAh g-1 at 5.0 A g-1 after 5000 cycles. Quantitative kinetics analysis confirms the fundamentals of the enhanced rate capacity and the potential region of Na-insertion/extraction. This elaborate work opens up an avenue toward the design of carbon with multidimensions and in-depth understanding of their sodium-storage features.

Microporous carbons derived from melamine and isophthalaldehyde: One-pot condensation and activation in a molten salt medium for efficient gas adsorption

In the present work, mixture of melamine and isophthalaldehyde undergo simultaneous polymerization, carbonization, and in situ activation in the presence of molten salt media through a single all-in-one route to design microporous carbons with high specific surface areas (~3000 m²/g). The effect of the activation temperature and molten salts on the polymerization process and final texture of the carbon was explored. Carbon materials prepared at 700 °C, in the presence of KOH (referred as MIK-700), exhibited a narrower pore-size distribution ~1.05 nm than those prepared in the presence of the eutectic KOH-NaOH mixture (MIKN). Additionally, MIK-700 possesses an optimum micropore volume (1.33 cm³/g) along with a high nitrogen content (2.66 wt%), resulting in the excellent CO₂ adsorption capacity of 9.7 mmol/g at 273 K and 1 bar. Similarly, the high specific area and highest total pore volume play an important role in H₂ storage at 77 K, with 4.0 wt% uptake by MIKN-800 (specific surface area and pore volume of 2984 m²/g and 1.98 cm³/g, respectively.) Thus, the facile one-step solvent-free synthesis and activation strategy is an economically favorable avenue for designing microporous carbons as an efficient gas adsorbents.

Nitrogen- and oxygen-containing micro–mesoporous carbon microspheres derived from m-aminophenol formaldehyde resin for supercapacitors with high rate performance

Nitrogen- and oxygen-containing micro–mesoporous carbon microspheres derived from m-aminophenol formaldehyde resin were prepared by the hydrothermal synthesis/carbonization/activation route for high-rate performance supercapacitor application.

A shiitake-derived nitrogen/oxygen/phosphorus co-doped carbon framework with hierarchical tri-modal porosity for high-performance electrochemical capacitors

A shiitake-derived N/O/P co-doped carbon framework with hierarchical tri-modal porosity was scalably fabricated, and exhibited exceptional supercapacitances, thanks to synergistic contributions from architectural/compositional merits.