A thermosetting phenolic resin with a pendant sulfonic acid group was prepared by reacting a resol-type phenolic resin (PF) with a Novalak-type sulfonated phenolic resin (SPF). Large amounts of gaseous molecules with similar and small size such as H2O and SO2 evolved in the range of 110 and 350 °C during the pyrolysis of this thermosetting phenolic resin (PF/SPF). Highly permeable carbon molecular sieve (CMS) membranes were obtained by pyrolysis of PF/SPF(45/55) precursor membranes which were dip-coated on porous alumina tubes. For example, the membrane pyrolyzed at 500 °C for 1.5 h displayed H2, CO2, and O2 permeances of 1950, 800, and 240 [GPU (gas permeation units) = 10-6 cm3(STP)·s-1·cm-2·cmHg-1], respectively, and ideal H2/CH4, CO2/CH4, and O2/N2 separation factors of 65, 27, and 5.2 at 35 °C and 1 atm, respectively. Sulfonic acid groups linked to thermostable polymer chains might act as “bonded templates” and showed attractive potential in the preparation of CMS membranes.

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Fabricating metal boride heterostructures and deciphering their interface interaction mechanism on accelerating polysulfide conversion at atomic levels are meaningful yet challenging in lithium–sulfur batteries (LSBs). Herein, novel highly‐conductive and binary sulfiphilic NbB2‐MXene heterostructures are elaborately designed with spontaneous built‐in electric field (BIEF) via a simple one‐step borothermal reduction strategy. Experimental and theoretical results reveal that Nb and B atoms can chemically bond with polysulfides, thereby enriching chemical anchor and catalytic active sites. Meanwhile, the spontaneous BIEF induces interfacial charge redistribution to make more electrons transferred to surface NbB2 sites, thereby weakening its strong adsorption property yet accelerating polysulfide transfer and electron diffusion on hetero‐interface, so providing moderate polysulfide adsorb‐ability yet decreasing sulfur‐species conversion energy barriers, further boosting the intrinsically catalytic activity of NbB2‐MXene for accelerated bidirectional sulfur conversion. Thus, S/NbB2‐MXene cathode presents high initial capacity of 1310.1 mAh g−1 at 0.1 C, stable long‐term lifespan with 500 cycles (0.076% capacity decay per cycle) at 1 C, and large areal capacity of 6.5 mAh cm−2 (sulfur loading: 7.0 mg cm−2 in lean electrolyte of 5 µL mgs−1) at 0.1 C. This work clearly unveils the mechanism of interfacial BIEF and binary sulfiphilic effect on accelerating stepwise sulfur conversion at atomic levels.

Electropolymerized ®lm of metal ethylenebis(salicylideneiminate) [(M(salen), M Co, Fe, Cu and Mn] was utilized as material for development of an electrochemical sensor for the determination of NO in solution. The sensors based on polymeric M(salen) were prepared by a means of electropolymerization with cyclic voltammetry (CV) in acetonitrile solution containing M(salen) for optimized cycles. Na®on was used as a second coating to the sensors and differential pulse amperometry (DPA) was used as a subsequent determination technique. The resulted sensors were found to display good activity toward the oxidation of NO with low detection limits and a good linear relationship between the current and NO concentration. The mechanism of the polymeric M(salen) modi®ed sensor was preliminarily studied by using a technique of quantum chemistry and proposed to be a three-dimensional catalytic pattern by conjugation of the electron of the NO molecule and the polymeric M(salen).

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sulfur) and gravimetric energy density (≈2,600 Wh kg −1 ). Nevertheless, there are still a lot of obstacles on the road of commercialization and practical development of LSBs. These obstacles mainly include: 1) The large volume expansion (≈80%), caused by the complex electrochemical reaction process, would damage the electrode structure and shorten their lifespan;2) The poor conductivities of active sulfur (5 × 10 −30 S cm −1 ) and its reaction product of Li 2 S (10 −13 S m −1 ) generate slow electrochemical reaction and large electrochemical polarization; 3) The most notoriously lithium polysulfides (LiPSs) shuttling seriously decreases the utilization rate of sulfur and the cycle life of LSBs. [5][6][7] On the basis of previous studies, the complex electrochemical discharge/charge reaction processes in LSBs always undergo a multiphase transformation of sulfur species with multistep charge transfer (S

Designing dense thick sulfur cathodes to gain high‐volumetric/areal‐capacity lithium–sulfur batteries (LSBs) in lean electrolytes is extremely desired. Nevertheless, the severe Li2S clogging and unclear mechanism seriously hinder its development. Herein, an integrated strategy is developed to manipulate Li2S redox kinetics of CoP/MXene catalyst via electron‐donor Cu doping. Meanwhile a dense S/Cu0.1Co0.9P/MXene cathode (density = 1.95 g cm−3) is constructed, which presents a large volumetric capacity of 1664 Ah L−1 (routine electrolyte) and a high areal capacity of ≈8.3 mAh cm−2 (lean electrolyte of 5.0 µL mgs−1) at 0.1 C. Systematical thermodynamics, kinetics, and theoretical simulation confirm that electron‐donor Cu doping induces the charge accumulation of Co atoms to form more chemical bonding with polysulfides, whereas weakens CoS bonding energy and generates abundant lattice vacancies and active sites to facilitate the diffusion and catalysis of polysulfides/Li2S on electrocatalyst surface, thereby decreasing the diffusion energy barrier and activation energy of Li2S nucleation and dissolution, boosting Li2S redox kinetics, and inhibiting shuttling in the dense thick sulfur cathode. This work deeply understands the atomic‐level manipulation mechanism of Li2S redox kinetics and provides dependable principles for designing high‐volumetric‐energy‐density, lean‐electrolyte LSBs through integrating bidirectional electro‐catalysts with manipulated Li2S redox and dense‐sulfur engineering.