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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 BN3 configuration. Compared to conventional graphitic N structures, the BN3 structure had a higher p-band center, ensuring superior adsorption and activation capabilities for TCE during the reaction. Within the BN3 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 nonmetallic catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solvent-redox hydrothermal process was employed to constructure MnO x –D oxides. • MnO x –D catalyst exhibites superior catalytic activity for aerobic oxidation of biomass–derived R–CH 2 –OH. • Adsorbed H 2 O on MnO x –D catalyst was found to enhance its superior catalytic activity. Manganese oxides (MnO x) have been emerged as highly active catalysts for the aerobic oxidation of biomass-derived compounds. Herein, a facile urea–redox hydrothermal method was employed to scalable synthesis of MnO x oxides with surface abundant unsaturated Mn and O species. The defective MnO x (MnO x –D) catalyst exhibits remarkable catalytic performance, enabling the room-temperature aerobic oxidation of biomass–derived alcohols with yields exceeding 99%. This represents a substantial 90.8-fold increase in activity compared to commercial MnO 2. Moreover, MnO x –D catalyst demonstrates broad substrate scopes for various biomass–derived alcohols and displays recyclability for the aerobic oxidative conversion of 5-hydroxymethylfurfural (HMF) over five cycles. Through a comprehensive analysis involving X–ray photoelectron spectroscopy (XPS), in–situ infrared (IR) spectroscopy, and controlled experiments, it is established that the presence of surface–adsorbed H 2 O species on MnO x –D catalyst significantly influences its catalytic performance. Mechanism studies reveal that the aerobic oxidation of biomass–derived R–CH 2 –OH compounds into the corresponding aldehydes can proceed via radical and non–radical pathways. Notably, the catalytic activity of MnO x –D catalyst in both pathways is mediated by the surface adsorbed H 2 O species. In the radical route, surface adsorbed H 2 O and O 2 species are converted into active •OH radical species, while in the non–radical route, surface adsorbed H 2 O can form a complex of HMF––H 2 O species. Both processes enhance the abstraction of H from the O–H and C–H bonds in the R–CH 2 –OH compounds on MnO x –D catalyst. This discovery could potentially guide the development of efficient metal oxidic catalysts for the oxidation of biomass–derived R–CH 2 –OH compounds. [ABSTRACT FROM AUTHOR]

Mechanism of SO 2 effect on mesoporous CuFeAlZrO x catalyst for simultaneous removal of Hg0 and NO. [Display omitted] • Amorphous CuFeAlZrO x catalysts with mesoporous structure were synthesized via a simple co-precipitation method. • The Cu 1 FeAlZrO x exhibited high catalytic activity and good SO 2 resistance at 275–390 ℃. • The synergistic effect of Cu and Fe tune the redox and acidity property with appropriate balance. • A possible mechanism for SO 2 effect on simultaneous removal of NO and Hg0 at wide temperature was proposed. Mesoporous CuFeAlZrO x catalyst is a promising substitute of V-based catalysts for potential candidate for simultaneous removal of Hg0 and NO due to its excellent performance at a broad temperature range. SO 2 poisoning effects remain a challenge in development of efficient SCR catalysts for applications. In this paper, the effect of SO 2 on mesoporous CuFeAlZrO x catalyst for simultaneous removal of Hg0 and NO at wide temperature range was studied. Relevant characterization techniques of H 2 -TPR, NH 3 -TPD, TG, SO 2 -TPD, XPS, Hg-TPD and in situ DRIFTS were used to reveal the correlativity between the physicochemical properties and SO 2 resistance of CuFeAlZrO x catalysts. SO 2 exhibited an inhibitory effect at low temperature (<300 °C) but a facilitative effect at high temperature(≥300 °C) for NH 3 -SCR reaction. At the same time, a promoting effect on Hg0 removal was observed during the whole temperature range. The deposition of NH 4 HSO 4 and the decrease of redox capacity caused the loss of SCR activity at low temperatures, while the formed iron sulfate provided more Lewis acid sites facilitate the high-temperature SCR performance due to the strong electron withdrawing effect of the S O double bonds. In addition, the generation of iron sulfates and NH 4 HSO 4 on mesoporous Cu 1 FeAlZrO x were alleviated because of the sacrifice of copper sites and promoted NH 4 HSO 4 decomposition in mesopore channels. SO 2 reacted with Hg0 to form HgSO 4 and Hg 2 SO 4 , which contributed to Hg0 removal performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • A possible mechanism for the simultaneous oxidation of NO and toluene was proposed. • A-site partial substitution with Co can tune the structural properties of La 1-x Co x FeO 3. • The poisoning effects of H 2 O on the performance was studied. • The Interplay between toluene oxidation and NO oxidation were explored. To provide insight into optimizing flue gas treatment, the reaction mechanism for simultaneous oxidation of NO and toluene with H 2 O using a A-site substituted La 1-x Co x FeO 3 (x = 0–0.4) catalysts with three-dimensional porous structure was investigated. The results demonstrated that the partial substitution of La in porous LaFeO 3 by Co can induce the structural distortion, promote the specific surface area, enhance more active site exposure and produce abundant reactive oxygen species, including lattice oxygen with higher mobility, more surface adsorbed oxygen as well as oxygen vacancies, which improved the catalytic activities remarkably. Besides, NO and toluene have mutual promoted effects in the reaction system. The inhibition effect of H 2 O on simultaneous oxidation of NO and toluene was confirmed in that H 2 O consumes the chemisorbed active oxygen atoms. Without H 2 O, absorbed NO reacts with chemisorbed oxygen to form NO 2 , and absorbed toluene is oxidized by lattice oxygen to generate intermediate species which finally completely oxidized into CO 2 and H 2 O. With H 2 O, H 2 O react with chemisorbed oxygen to produce OH species that occupied active sites for toluene adsorption. NO interacts with OH species to form stable nitrate species, which offsets the inhibitive effect of H 2 O on NO oxidation due to the consumption of chemisorbed oxygen. [ABSTRACT FROM AUTHOR]

Deuterohemin-β-Ala-His-Thr-Val-Glu-Lys (DhHP-6), a novel Deuterohemin-containing peptide mimetic of natural microperoxidase-11 (MP-11), was successfully immobilized onto NH 2 -UIO-66 (ZrMOF) by precipitation and cross-linking strategy to obtain a peroxidase mimetic, DhHP-6- c -ZrMOF. The synergy between components offers DhHP-6- c -ZrMOF excellent kinetics performance, peroxidase activity, pH stability, and phenol degradation capacity. Up to 98.0% of phenol could be degraded in 120 min when utilizing DhHP-6- c -ZrMOF as heterogeneous Fenton catalyst. Notably, DhHP-6- c -ZrMOF delivered outstanding recoverability with an 80.2% degradation ratio of phenol after four recycles. The efficient peroxidase mimetic can potentially be used as a promising catalyst for the high-efficiency degradation of phenol pollutants. Unlabelled Image • Precipitation and cross-linking strategy for construction of peroxidase mimetic (DhHP-6- c -ZrMOF). • Characterization of the immobilization of DhHP-6 onto ZrMOF. • DhHP-6- c -ZrMOF delivered enhanced kinetics performance, peroxidase activity, pH stability. • Synergistic mechanism offers the material excellent phenol degradation capacity and recoverability. [ABSTRACT FROM AUTHOR]