Development of efficient sorbents for carbon dioxide (CO) capture from flue gas or its removal from natural gas and landfill gas is very important for environmental protection. A new series of heteroatom-doped porous carbon was synthesized directly from pyrazole/KOH by thermolysis. The resulting pyrazole-derived carbons (PYDCs) are highly doped with nitrogen (14.9-15.5 wt %) as a result of the high nitrogen-to-carbon ratio in pyrazole (43 wt %) and also have a high oxygen content (16.4-18.4 wt %). PYDCs have a high surface area (SA = 1266-2013 m g), high CO Q (33.2-37.1 kJ mol), and a combination of mesoporous and microporous pores. PYDCs exhibit significantly high CO uptakes that reach 2.15 and 6.06 mmol g at 0.15 and 1 bar, respectively, at 298 K. At 273 K, the CO uptake improves to 3.7 and 8.59 mmol g at 0.15 and 1 bar, respectively. The reported porous carbons also show significantly high adsorption selectivity for CO/N (128) and CO/CH (13.4) according to ideal adsorbed solution theory calculations at 298 K. Gas breakthrough studies of CO/N (10:90) at 298 K showed that PYDCs display excellent separation properties. The ability to tailor the physical properties of PYDCs as well as their chemical composition provides an effective strategy for designing efficient CO sorbents.

The rechargeable lithium-sulfur (Li-S) battery is a promising candidate for the next generation of energy storage technology,o wing to the high theoreticalc apacity,h igh specific energy density,a nd low cost of electrode materials. The main drawbacks in the development of long-life Li-S batteries are capacity fading and the sluggish kinetics at the cathode caused by the polysulfides shuttle. These limitations are addressed through the design of novel nanocagesc ontaining cobalt phosphide (CoP) nanoparticles embedded in highly porousnitrogen-doped carbon (CoP-N-GC) by thermal annealing of ZIF-67 in ar eductivea tmosphere followed by a phosphidation step using sodium hypophosphite. The CoP nanoparticles, with large surface area and uniform homogeneous distribution within the N-doped nanocage graphitic carbon,a ct as electrocatalysts to suppress the shuttle of soluble polysulfides through strong chemical interactions and catalyze the sulfur redox. As ar esult,t he S@CoP-N-GC electrode delivers an extremely high specific capacity of 1410 mA hg À1 at 0.1 C(1C= 1675 mA g À1)w ith an excellent coulombic efficiency of 99.7 %. Moreover,c apacity retention from 864 to 678 mA hg À1 is obtained after 460 cycles with a very low decay rate of 0.046 %p er cycle at 0.5 C. Therefore, the combination of the CoP catalyst and polar conductive porousc arbon effectively stabilizes the sulfur cathode, enhancing the electrochemical performance and stabilityo f the battery.

While transition‐metal oxides such as α‐MoO3 provide high capacity, their use is limited by modest electronic conductivity and electrochemical instability in aqueous electrolytes. Two‐dimensional (2D) MXenes, offer metallic conductivity, but their capacitance is limited in aqueous electrolytes. Insertion of partially solvated cations into Ti3C2 MXene from lithium‐based water‐in‐salt (WIS) electrolytes enables charge storage at positive potentials, allowing a wider potential window and higher capacitance. Herein, we demonstrate that α‐MoO3/Ti3C2 hybrids combine the high capacity of α‐MoO3 and conductivity of Ti3C2 in WIS (19.8 m LiCl) electrolyte in a wide 1.8 V voltage window. Cyclic voltammograms reveal multiple redox peaks from α‐MoO3 in addition to the well‐separated peaks of Ti3C2 in the hybrid electrode. This leads to a higher specific charge and a higher rate capability compared to a carbon and binder containing α‐MoO3 electrode. These results demonstrate that the addition of MXene to less conductive oxides eliminates the need for conductive carbon additives and binders, leads to a larger amount of charge stored, and increases redox capacity at higher rates. In addition, MXene encapsulated α‐MoO3 showed improved electrochemical stability, which was attributed to the suppressed dissolution of α‐MoO3. The work suggests that oxide/MXene hybrids are promising for energy storage.

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Palladium catalyzed cross-coupling reactions represent a significant advancement in contemporary organic synthesis as these reactions are of strategic importance in the area of pharmaceutical drug discovery and development. Supported palladium-based...