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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]

Mechanism of SO 2 effect on Cu 1-x Fe x CeZr catalysts for simultaneous removal of NO and toluene. [Display omitted] • The correlativity between the the reaction process and sulfur poisoning was studied. • The mechanism effect of SO 2 on the reaction process was studied. • A mechanism for simultaneous removal of NO and toluene was proposed. • The introduction of Fe enhanced oxygen vacancies formation and oxygen mobility. Developing non-vanadium-based SCR catalysts with high performances for simultaneous removal of NO and toluene at low-medium temperatures remains a challenge in addressing SO 2 poisoning. Herein, porous Fe-modified CuCeZr catalysts prepared via KIT-6 hard-templating method was conducted to investigate the simultaneous removal of NO and toluene at low-medium temperatures. A suite of experiments and characterizations was systematically used to probe into the effect of SO 2 on the reaction process. The results indicated that porous Fe-modified CuCeZr displayed excellent performance for simultaneous removal of NO and toluene. The introduction of Fe into CuCeZr enhances both acid sites and redox properties via the redox cycle between Cu2++Ce3+↔Cu++Ce4+ and Fe3++Ce3+↔Fe2++Ce4+ redox cycle. Importantly, Fe incorporation leads to the formation of lattice defects and oxygen vacancies, generating abundant active sites that mitigate the detrimental effects of SO 2 poisoning, and promote the efficient removal of NO and toluene simultaneously. Besides, a mechanism influence of SO 2 on the reaction process for simultaneous removal of NO and toluene at low-medium temperatures was proposed. This mechanism has the potential to provide an effective solution for developing non-vanadium-based SCR catalysts with sulfur resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] As a renewable green energy, hydrogen has received widespread attention due to its huge potential in solving energy shortages and environment pollution. In this paper, a one-step solvothermal method was applied to grow ultra-thin g-C 3 N 4 (UCN) nanosheets and NiS nanoparticles on the surface of ZnIn 2 S 4 (ZIS). A ternary NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 composite material with dual high-speed charge transfer channels was constructed for the advancement of the photocatalytic H 2 generation. The optimal ternary catalyst 1.5wt.%NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 (NiS/ZIS/UCN) achieved a H 2 evolution yield reached to 5.02 mmolg−1h−1, which was 5.23 times superior than that of pristine ZnIn 2 S 4 (0.96 mmolg−1h−1) and even outperform than that of the best precious metal modified 3.0 wt%Pt/ZnIn 2 S 4 (4.08 mmolg−1h−1). The AQY at 420 nm could be achieved as high as 30.5%. The increased photocatalytic performance of NiS/ZIS/UCN could be ascribed to the type-I heterojunctions between intimated ZIS and UCN. In addition, NiS co-catalyst with large quantity of H 2 evolution sites, could result in efficient photo-induced charges separation and migration. Furthermore, the NiS/ZIS/UCN composite exhibited excellent H 2 evolution stability and recyclability. This work would also offer a reference for the design and synthesis of ternary co-catalyst with heterojunction composite for green energy conversion. [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]