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Carbon reactive capture and conversion offers a sustainable route to valuable chemicals and fuels while aiding GHG reduction. Direct electrochemical conversion of capture solutions like bicarbonate avoids the energy demands... 

Four metalloporphyrinic metal–organic frameworks (MOFs) were successfully synthesized and exhibited enhanced activities for the photooxidation of a sulfur mustard simulant, 2-chloroethyl ethyl sulfide (CEES). Among them, a Sn-porphyrin functionalized 2D MOF, namely CSLA-21-NH2(Sn), showed a half-life of 1.5 min for CEES oxidation under blue LED, featuring as one of the fastest photocatalysts for CEES degradation. 

Rational catalyst design and optimal solvent selection are key to advancing biorefining. Here, we explored the organocatalytic isomerization of d-fructose to a valuable rare monosaccharide, d-allulose, as a function of solvent. The isomerization of d-fructose to d-allulose competes with its isomerization to d-glucose and sugar degradation. In both water and DMF, the catalytic activity of amines towards d-fructose is correlated with their basicity. Solvents impact the selectivity significantly by altering the tautomeric distribution of d-fructose. Our results suggest that the furanose tautomer of d-fructose is isomerized to d-allulose, and the fractional abundance of this tautomer increases as follows: water < MeOH < DMF ≈ DMSO. Reaction rates are also higher in aprotic than in protic solvents. The best d-allulose yield, 14 %, was obtained in DMF with 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as the catalyst. The reaction kinetics and mechanism were explored using operando NMR spectroscopy. 

Abstract Carbon–carbon bond cleavage reactions, adapted to deconstruct aliphatic hydrocarbon polymers and recover the intrinsic energy and carbon value in plastic waste, have typically been catalysed by metal nanoparticles or air-sensitive organometallics. Metal oxides that serve as supports for these catalysts are typically considered to be inert. Here we show that Earth-abundant, non-reducible zirconia catalyses the hydrogenolysis of polyolefins with activity rivalling that of precious metal nanoparticles. To harness this unusual reactivity, our catalytic architecture localizes ultrasmall amorphous zirconia nanoparticles between two fused platelets of mesoporous silica. Macromolecules translocate from bulk through radial mesopores to the highly active zirconia particles, where the chains undergo selective hydrogenolytic cleavage into a narrow, C 18 -centred distribution. Calculations indicated that C–H bond heterolysis across a Zr–O bond of a Zr(O) 2 adatom model for unsaturated surface sites gives a zirconium hydrocarbyl, which cleaves a C–C bond via β-alkyl elimination. 

Single-atom metal embedded in nitrogen-doped carbon show high HER performance, with Co-NAC reaching 200 mA cm⁻²at 310 mV overpotential. 

Abstract Effective control on chemoselectivity in the catalytic hydrogenation of C=O over C=C bonds is uncommon with Pd‐based catalysts because of the favored adsorption of C=C bonds on Pd surface. Here we report a unique orthorhombic PdSn intermetallic phase with unprecedented chemoselectivity toward C=O hydrogenation. We observed the formation and metastability of this PdSn phase in situ. During a natural cooling process, the PdSn nanoparticles readily revert to the favored Pd₃Sn₂phase. Instead, using a thermal quenching method, we prepared a pure‐phase PdSn nanocatalyst. PdSn shows an >96 % selectivity toward hydrogenating C=O bonds of various α,β‐unsaturated aldehydes, highest in reported Pd‐based catalysts. Further study suggests that efficient quenching prevents the reversion from PdSn‐ to Pd₃Sn₂‐structured surface, the key to the desired catalytic performance. Density functional theory calculations and analysis of reaction kinetics provide an explanation for the observed high selectivity.