Carbon nano-onion induced organization of polyacrylonitrile-derived block star polymers to obtain mesoporous carbon materials

Mesoporous Carbon Composites Containing Carbon Nanostructures: Recent Advances in Synthesis and Applications in Electrochemistry

Carbon nanostructures (CNs) are various low-dimensional allotropes of carbon that have attracted much scientific attention due to their interesting physicochemical properties. It was quickly discovered that the properties of CNs can be significantly improved by modifying their surface or synthesizing composites containing CNs. Composites combine two or more materials to create a final material with enhanced properties compared with their initial components. In this review, we focused on one group of carbon materials-composites containing CNs (carbon/CN composites), characterized by high mesoporosity. Particular attention was paid to the type of synthesis used, divided into hard- and soft-templating methods, the type of polymer matrix precursors and their preparation method, heteroatom doping, pore formation methods, and correlations between the applied experimental conditions of synthesis and the structural properties of the composite materials obtained. In the last part, we present an updated summary of the applications of mesoporous composites in energy storage systems, supercapacitors, electrocatalysis, etc. The correlations among porous structures of materials, heteroatom doping, and electrochemical or catalytic efficiency, including activity, selectivity, and stability, were also emphasized. To our knowledge, a single review has never summarized pyrolyzed mesoporous composites of polymer-CNs, their properties and applications in electrochemistry.

Markedly boosted peroxymonosulfate- and periodate-based Fenton-like activities of iron clusters on sulfur/nitrogen codoped carbon: Key roles of a sulfur dopant and compared activation mechanisms

Highly dispersed iron nanoclusters on carbon (FeNC@C) hold great promise for wastewater purification in Fenton-like reactions. The microenvironment engineering of central Fe atom is promising to boost the activation capacity of FeNC@C, which is however remains a challenge. This study developed a self-sacrificed templating strategy to S, N-codoped carbon supported Fe nanoclusters (FeNC@SNC) activator and find the key role of sulfur heteroatoms in regulating the electron structure of Fe sites and final activation property. Investigations revealed that the FeNC@SNC composite exhibited unusual bifunctional activity in both peroxymonosulfate (PMS)- and periodate (PI)-based Fenton-like reactions. We also offered insights into the differences between the degradation of organics by the FeNC@SNC/PMS and FeNC@SNC/PI systems. Specifically, under identical conditions, the FeNC@SNC/PMS system delivered a higher oxidation capability and stronger resistance to nontarget matrix constituents, but showed more severe Fe leaching than the FeNC@SNC/PI system. Furthermore, while mediated electron-transfer process was identified as the major route for pollutant decomposition in both systems, the high-valent Fe-oxo species [Fe (IV)] was the auxiliary reactive species found only in the FeNC@SNC/PMS system. Based on these findings, our results provide profound insights into the design of active and durable Fe-based activators toward highly efficient Fenton-like reactions.