Predicting Capacity of Hard Carbon Anodes in Sodium-Ion Batteries Using Porosity Measurements

We report an inverse relationship between measurable porosity values and reversible capacity from sucrose-derived hard carbon as an anode for sodium-ion batteries (SIBs). Materials with low measureable pore volumes and surface areas obtained through N₂ sorption yield higher reversible capacities. Conversely, increasing measurable porosity and specific surface area leads to sharp decreases in reversible capacity. Utilizing a low porosity material, we thus are able to obtain a reversible capacity of 335 mAh g⁻¹. These findings suggest that sodium-ion storage is highly dependent on the absence of pores detectable through N₂ sorption in sucrose-derived carbon

Anomalous thermo-osmotic conversion performance of ionic covalent-organic-framework membranes in response to charge variations

Authors of the article systematically investigated how the membrane charge populations affect permselectivity by decoupling their effects from the impact of the pore structure using a multivariate strategy for constructing covalent-organic-framework membranes. The complex interplay between pore-pore interactions in response to charge variations for ion transport across the upscaled nanoporous membranes helps explain the obtained results. This study has far-reaching implications for the rational design of ionic membranes to augment energy extraction rather than intuitively focusing on achieving high densities

Converging Cooperative Functions into the Nanospace of Covalent Organic Frameworks for Efficient Uranium Extraction from Seawater

Article reports a new strategy for efficient extraction of uranium from seawater via converging the cooperative functions of adsorption–photocatalysis into the nanospace of covalent organic frameworks (COFs). This study establishes multicomponent COFs as promising candidates for efficient uranium extraction from seawater

Guanidinium-based covalent organic framework membrane for single-acid recovery

Article discusses how, although acids are extensively used in contemporary industries, time-consuming and environmentally unfriendly processes hinder single-acid recovery from wastes containing various iconic species. The authors rationally designed a membrane with uniform angstrom-sized pore channels and built-in charge-assisted hydrogen bond donors that preferentially conducted HCl while exhibiting negligible conductance for other compounds

Reducing CO₂ to dense nanoporous graphene by Mg/Zn for high power electrochemical capacitors

Converting CO2 to valuable materials is attractive.Herein, we report using simple metallothermic reactions to reduce atmospheric CO2 to dense nanoporous graphene. By using a Zn/Mg mixture as a reductant, the resulted nanoporous graphene exhibits highly desirable properties: high specific surface area of 1900 m2/g, a great conductivity of 1050 S/m and a tap density of 0.63 g/cm3, comparable to activated carbon. The nanoporous graphene contains a fine mesoporous structure constructed by curved few-layer graphene nanosheets. The unique property ensemble enables one of the best high-rate performances reported for electrochemical capacitors: a specific capacitance of ~170F/g obtained at 2000 mV/s and 40 F/g at a frequency of 120 Hz. This simple fabricating strategy conceptually provides opportunities for materials scientists to design and prepare novel carbon materials with metallothermic reactions.This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/nano-energy/.Keywords: Magnesiothermic reduction, Nanoporous graphene, CO₂ reduction, Electrochemical capacitor

Regulating C2H2/CO2 adsorption selectivity by electronic-state manipulation of iron in metal-organic frameworks

Article reports a metal electronic-state manipulation strategy to construct a pair of isostructural and interconvertible Fe-MOFs featuring open Fe centers with different electron densities for efficient C₂H₂/CO₂ separation. The authors show that the presence of Fe[II] centers with a medium-spin-state trail plays a crucial role in the enhanced C₂H₂ selective adsorption

BnMs3 is required for tapetal differentiation and degradation, microspore separation, and pollen-wall biosynthesis in Brassica napus

7365AB, a recessive genetic male sterility system, is controlled by BnMs3 in Brassica napus, which encodes a Tic40 protein required for tapetum development. However, the role of BnMs3 in rapeseed anther development is still largely unclear. In this research, cytological analysis revealed that anther development of a Bnms3 mutant has defects in the transition of the tapetum to the secretory type, callose degradation, and pollen-wall formation. A total of 76 down-regulated unigenes in the Bnms3 mutant, several of which are associated with tapetum development, callose degeneration, and pollen development, were isolated by suppression subtractive hybridization combined with a macroarray analysis. Reverse genetics was applied by means of Arabidopsis insertional mutant lines to characterize the function of these unigenes and revealed that MSR02 is only required for transport of sporopollenin precursors through the plasma membrane of the tapetum. The real-time PCR data have further verified that BnMs3 plays a primary role in tapetal differentiation by affecting the expression of a few key transcription factors, participates in tapetal degradation by modulating the expression of cysteine protease genes, and influences microspore separation by manipulating the expression of BnA6 and BnMSR66 related to callose degradation and of BnQRT1 and BnQRT3 required for the primary cell-wall degradation of the pollen mother cell. Moreover, BnMs3 takes part in pollen-wall formation by affecting the expression of a series of genes involved in biosynthesis and transport of sporopollenin precursors. All of the above results suggest that BnMs3 participates in tapetum development, microspore release, and pollen-wall formation in B. napus

Functionalized porous organic polymers for olefin/paraffin separations

Compositions containing a porous organic polymer and a monovalent metal cation are provided for separation/purification of olefins and paraffins. The compositions can be stable and recyclable. The compositions can contain acidic functional group having monovalent metal cations associated therein. The monovalent metal cations can include Ag(I) and Cu(I), capable of strong cation-pi binding to ethylene and other olefins. The compositions can have a large surface area greater than about 20 m2/g. The compositions can be used to separate/purify mixtures of ethylene and ethane. The compositions can have an ethylene/ethane adsorption selectivity of about 20 to 500 at 296 K. Methods of making the compositions are provided. Methods can include synthesizing the porous organic polymer, grafting acidic functional groups onto the polymer, and cation exchange with a salt or acid of a monovalent metal cation. Methods of olefin/paraffin separation are provided capable of achieving purities over 99%