Highly efficient catalyst for 1,1,2-trichloroethane dehydrochlorination via BN_(3) frustrated Lewis acid-base pairs

In this study,a novel non-metallic carbon-based catalyst co-doped with boron and nitrogen(B,N)was successfully synthesized.By precisely controlling the carbonization temperature of a binary mixed ionic liquid,we selectively modified the doping site structure,ultimately constructing a B,N co-doped frustrated Lewis acid-base pair catalyst.This catalyst exhibited remarkable catalytic activity,selectivity,and stability in the dehydrochlorination reaction of 1,1,2-trichloroethane(TCE).Detailed characterization and theoretical calculations revealed that the primary active center of this catalyst was the BN_(3)configuration.Compared to conventional graphitic N structures,the BN_(3)structure had a higher p-band center,ensuring superior adsorption and activation capabilities for TCE during the reaction.Within the BN_(3)site,three negatively charged nitrogen atoms acted as Lewis bases,while positively charged boron atoms acted as Lewis acids.This synergistic interaction facilitated the specific dissociation of chlorine and hydrogen atoms from TCE,significantly enhancing the 1,1-dichloroethene selectivity.Through this research,we not only explored the active site structure and catalytic mechanism of B,N co-doped catalysts in depth but also provided an efficient,selective,and stable catalyst for the dehydrochlorination of TCE,contributing significantly to the development of non-metallic catalysts.

Efficient nitrite-to-ammonia electroreduction over Zr-Ni frustrated Lewis acid-base pairs

Electrochemical NO_(2)~--to-NH_(3) conversion(NO_(2)RR) offers a green route to NH_(3) electrosynthesis, while developing efficient NO_(2)RR catalysis systems at high current densities remains a grand challenge. Herein, we report an efficient Zr-NiO catalyst with atomically dispersed Zr-dopants incorporated in NiO lattice, delivering the exceptional NO_(2)RR performance with industriallevel current density(>0.2 A cm^(-2)). In situ spectroscopic measurements and theoretical simulations reveal the construction of ZrNi frustrated Lewis acid-base pairs(FLPs) on Zr-Ni O, which can substantially increase the number of absorbed nitrite(NO_(2)~-),promote the activation and protonation of NO_(2)~- and concurrently hamper the H coverage, boosting the activity and selectivity of Zr-NiO towards the NO_(2)RR. Remarkably, Zr-NiO exhibits the exceptional performance in a flow cell with high Faradaic efficiency for NH_(3) of 94.0% and NH_(3)yield rate of 1,394.1 μmol h^(-1)cm^(-2) at an industrial-level current density of 228.2 m A cm^(-2),placing it among the best NO_(2)RR electrocatalysts for NH_(3) production.

Recent advances in selective C–C bond coupling for ethanol upgrading over balanced Lewis acid-base catalysts

Ethanol is a considerable platform molecule in biomass conversion,which could be acquired in quantity through acetone-butanol-ethanol(ABE)fermentation.People have been working on the upgrading of ethanol to value added chemicals for decades.In the meantime,1-butanol and a series of value added products have been selectively generated through C–C bond coupling.In this mini-review,we focus on the recent advances in selective C–C bond formation over balanced Lewis acid-base catalysts such as modified metal oxide,mixed metal oxide,hydroxyapatite and zeolite confined transition metal oxide catalysts.Among them,Pd-MgAlO_x and Sr-based hydroxyapatite exhibit>70%1-butanol selectivity,while Zn——xZr_yO_z and Ta-Si BEA zeolite achieve>80%of isobutene and butadiene selectivity respectively.The mechanism and reaction pathway of C–C bond formation in each reaction system are described in detail.The correlation between C–C bond coupling and the acidity/basicity of the Lewis acid-base pairs from the surface of the catalysts are also discussed.