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Here, an approach to produce a hierarchical porous Fe‐N‐C@TABOH catalyst with densely accessible high intrinsic active FeNx sites is proposed. The method involves a single‐step pyrolysis of Zn/Fe‐zeolitic imidazolate framework (Zn/Fe‐ZIF‐H) with tetrabutylammonium hydroxide (TABOH) micelles, which is obtained by utilizing TABOH as a structural template and electronic mediator at room temperature for a brief duration of 16 min. Notably, the yield of Zn/Fe‐ZIF‐H is 3.5 times that of Zn/Fe‐ZIF‐N prepared by conventional method. Results indicate that in addition to expediting synthesis and increasing yield of the Zn/Fe‐ZIF‐H, the TABOH induces a hierarchical porous structure and fosters the formation of more and higher intrinsic active FeNx moieties in Fex‐N‐C@TABOH, showing that TABOH is a multifunctional template. Crucially, the increased mesoporosity/external surface area and optimized microenvironment of Fe‐N‐C@TABOH significantly enhance ORR activity by facilitating the formation of high intrinsic active FeNx sites, increasing accessible FeNx sites, and reducing mass transfer resistance. Through structure tailoring and microenvironment optimization, the resulting Fe‐N‐C@TABOH exhibits superior ORR performance. DFT calculation further validates that the synergistic effect of these two factors leads to low ORR barrier and optimized *OH adsorption energy. This study underscores the importance of structure and electronic engineering in the development of highly active ORR catalysts. [ABSTRACT FROM AUTHOR]

Rhodium as a national strategic reserve metal, has the irreplaceable role of other metals, but its resources are mainly concentrated in some countries in South Africa, and rhodium resources are very scarce in our country. In the process of industrialization in China, a large number of rhodium-containing homogeneous spent rhodium catalysts are produced, of which rhodium content is much higher than that of ores, so it is particularly important to recover rhodium from rhodium-containing homogeneous spent catalysts. By referring to the relevant literature, this paper summarized the recycling methods and prospected its prospects. [ABSTRACT FROM AUTHOR]

To deeply understand the role of P in hydrodeoxygenation (HDO), SiO2-supported Ni and Ni–P catalysts with different P/Ni ratios (x) were prepared. The as-prepared samples were characterized by various characterization methods. The HDO activity and product distribution over the Ni/SiO2 and N–P/SiO2-x were compared and the effects of x on the structure, acidity, formation mechanism of active phases and HDO performance were studied taking m-cresol HDO as a model reaction. The results showed that the introduction of P promotes the formation of smaller active sites and contributes to the creation of weak and medium strength acid sites through the formation of P–OH groups and Niδ+ in Ni2P. HDO over the Ni/SiO2 catalyst occurs mainly via the hydrogenation (HYD) route with 3-methyl-cyclohexanol (3-MCHnol) as the main product. However, for Ni–P/SiO2-x catalysts, methyl-cyclohexane (MCH) selectivity increases first and then decreases with the increase of x, reaching a maximum of 95% at x = 1. The acidity generated by the introduction of P contributes to increased MCH selectivity, while the dehydration of 3-MCHnol to MCH occurs mainly on acid sites. However, the excessively high P content (x ≥ 2.0) leads to a significant increase of MB (toluene) selectivity, which is associated with the increase in Ni(I) sites. About 100% m-cresol conversion was achieved with Ni–P/SiO2-1.0 when the m-cresol (g)/catalyst (g) ratio was 3, with MCH (99.4%) as the major product, showing great promise for deep HDO catalysis. [ABSTRACT FROM AUTHOR]

Background: Most dyes are toxic, carcinogenic, and mutagenic, all of which cause severe harm to human health and the environment. Therefore, it is essential to find the most suitable method to treat dye wastewaters before discharge. In this study, the natural Ca‐type montmorillonite (Ca‐MMT) was activated by HNO3 (20 wt.%) solution under different temperatures to obtain acid‐activated MMT (Acid‐MMT). Fe (10 wt.%) was supported on Acid‐MMT (Fe/Acid‐MMT) via the impregnation method using Fe(NO3)3·9H2O as a precursor. Meanwhile, the removal of methylene blue (MB) by heterogeneous Fenton‐like reaction using Fe/Acid‐MMT as catalyst was evaluated. The material was characterized by Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), X‐ray photoeletron spectroscopy (XPS), scanning electron microscopy (SEM), N2 adsorption–desorption at low temperature, and the temperature program desorption of NH3 (NH3‐TPD) techniques. Results: The acidity and textural properties of the Acid‐MMT were adjusted by varying the acid activation temperature. Moreover, the amount of acidity and the surface area of the catalyst had a noticeable effect on the removal efficiency of MB. Fe‐supported Acid‐MMT activated by HNO3 at 100°C (Fe/Acid‐MMT‐100) catalyst exhibited the highest removal efficiency of MB. The removal efficiency of the MB was more than 97.8% under the following reaction conditions: H2O2 concentration of 0.85 mmol·L−1, Fe/Acid‐MMT‐100 dosage of 0.75 g°L−1, temperature of 50°C, and initial solution pH of 3.0–9.0. Conclusion: An efficient Fe/Acid‐MMT catalyst for a Fenton‐like reaction was obtained by optimizing the acid treatment temperature of Ca‐MMT. The synergistic effect between its excellent adsorption ability and the ∙OH generated from H2O2 activated by Fe/Acid‐MMT would enhance MB removal efficiency in a Fenton‐like system. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Electrosynthesis offers an efficient and sustainable strategy for the conversion of biomass‐derived platform molecules. Among this process, developing efficient and cost‐effective electrocatalysts is of vital importance. We report herein the preparation of the nanocrystalline PbO‐In2O3 catalysts for the electrocatalytic reduction of levulinic acid (LA) to valeric acid (VA). A series of non‐noble nanocrystalline PbO‐In2O3 composite materials with different molar compositions were prepared and thoroughly characterized. The prepared nanocrystalline PbO‐In2O3 composite materials were used as working electrode for the electrocatalytic hydrogenation of LA in an H‐type electrolytic cell. A LA conversion of 41.4 % and VA selectivity of 97.8 % was achieved with the VA faradic efficiency of 89.2 % under the high current density of 134 mA cm−2. This is the first report on the electrocatalytic reduction of LA to VA using PbO‐In2O3 composite electrode catalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] As an important heterogeneous catalyst, Titanium Silicalite-1 (TS-1) zeolite has been widely applied in various catalytic processes. Here, hierarchical TS-1 single-crystals were successfully synthesized by a steam-assisted crystallization strategy using hierarchically porous titanium-containing silica (Ti-NKM-5) as a precursor. Due to the presence of large mesopores (10–40 nm)， the microporous structure-directing agents penetrated the interstitial structure of silica particles, inducing the dissolution and crystallization process. During crystallization, the generated nanocrystals grew together to form a hierarchical structure. Titanium was fully incorporated into the zeolite framework, and no extra-framework anatase was formed. Compared with the traditional microporous TS-1 zeolite, the synthesized hierarchical TS-1 single-crystal exhibited superior catalytic performance in oxidative desulfurization (ODS) of dibenzothiophene (DBT) and 4, 6-dimethyl dibenzothiophene (4, 6-DMDBT) owing to the hierarchically porous and anatase-free structure. The recycling test revealed the durability of the obtained hierarchical TS-1 catalyst under moderate reaction conditions. [ABSTRACT FROM AUTHOR]

Simultaneous removal of Hg0 and H2S over a regenerable activated coke supported Fe2O3 catalyst (Fe2O3/AC) was studied in simulated coal-derived syngas. It was found that the Fe2O3/AC catalyst exhibited high capability for Hg0 and H2S removal, which was attributed to the catalytic oxidation activity of Fe2O3. Its capability for Hg0 and H2S removal increased with an increase of Fe2O3 loading amount, and the highest was at 150 °C for Hg0 removal. CO and H2 showed no obvious effect on Hg0 removal by Fe2O3/AC, while H2S had a promotion effect, which was due to S and FeSx produced by the H2S reaction on Fe2O3/AC. The results of SEM-EDX and the temperature programmed desorption experiment (TPD) revealed that Fe2O3 played a critical role in Hg0 oxidation, and HgS was generated upon the reaction of Hg0 with H2S on Fe2O3/AC. The used Fe2O3/AC catalyst after Hg0 and H2S removal could be effectively regenerated and still had high capability for Hg0 and H2S removal. [ABSTRACT FROM AUTHOR]

• Co 3 O 4 -ZIF/Zn was successfully prepared by bimetallic Co/Zn leaf blade structure template. • The bimetallic Co/Zn can promote more evenly distributed mesopores, abundant smaller active Co 3 O 4 sites and higher N content. • Co 3 O 4 -ZIF/Zn follows a four-electron transfer path. • Co 3 O 4 -ZIF/Zn showed better ORR performance and stability than Co 3 O 4 -ZIF prepared with Co-ZIF-67 template. The design of highly active non-noble metal oxidation reduction catalysts (ORR) for microbial fuel cell (MFC) has always been a challenge. The aim of this study is to develop a highly active low cost cobalt-based ORR catalyst for MFCs cathode. Herein, a series of highly active nitrogen doped Co 3 O 4 -ZIF/Zn-T catalysts with different calcination temperatures (T) were prepared using bimetallic Co/Zn leaf blade structure Co-ZIF/Zn-67 as template. The Co 3 O 4 -ZIF/Zn- T catalysts were characterized by various methods, and the effect of T on the structure and ORR performance of MFC catalyst were studied. The results showed that the Co 3 O 4 -ZIF/Zn-T derived from bimetallic Co/Zn leaf blade structure Co-ZIF/Zn-67 template exhibited better ORR performance than Co 3 O 4 -ZIF-400 derived from the dodecahedral structure Co-ZIF-67 template. The bimetallic Co/Zn Co-ZIF/Zn-67 template promotes more uniformly distributed mesopores, high N content and abundant smaller active Co 3 O 4 sites due to its particular structure and the isolation effect of Zinc. Among Co 3 O 4 -ZIF/Zn- T catalysts, the Co 3 O 4 -ZIF/Zn-400 calcined at 400 °C demonstrated the highest ORR performance (onset potential was 0.082 V and MFC power density was 656.9 mw/m2), which was much higher than Co 3 O 4 -ZIF-400 (0.027 V and 402.8 mw/m2). The output voltage of MFC with Co 3 O 4 -ZIF/Zn-T exhibited no significant downward trend in 30 days stability test, indicating that the Co 3 O 4 -ZIF/Zn-400 catalyst has great stability. [ABSTRACT FROM AUTHOR]

Hydrogenation reactions are an important process in today's chemical industry. Typically, hydrogenation reactions involve the removal of an unsaturated bond in olefins or other polyenes via thermal catalysis using hydrogen. As hydrogenation reactions are often carried out at temperatures up to several hundred degrees, they require significant energy input which typically comes from burning fossil fuels. In order to conserve fossil fuels and reduce CO2 emissions, researchers are now developing photothermal catalysts for hydrogenation reactions, which harness concentrated sunlight to achieve the required reaction temperatures or introduce sunlight into thermal-driven reaction systems to reduce the reaction temperatures. Photothermal catalysts thus need to be able to efficiently absorb sunlight, whilst also being able to drive the desired hydrogenation reaction with high activity and selectivity. In this review, we summarize recent research aimed at the development of photothermal catalysts for CO2/CO hydrogenation and alkene/alkyne/aromatic hydrogenation. Particular emphasis is placed on uncovering the reaction mechanisms at the molecular level, which in turn guides the rational design of photothermal catalysts with better performance. [ABSTRACT FROM AUTHOR]

O‐heterocycles have wide applications, and their efficient and green synthesis is very interesting. Herein, we report hydrogen‐bonding catalyzed ring‐closing metathesis of aliphatic ethers to O‐heterocycles over ionic liquid (IL) catalyst under metal‐ and solvent‐free conditions. The IL 1‐butylsulfonate‐3‐methylimidazolium trifluoromethanesulfonate ([SO3H‐BMIm][OTf]) is discovered to show outstanding performance, better than the reported catalysts. An interface effect plays an important role in mediating the reaction rate due to the immiscibility between the products and the IL catalyst, and the products can be spontaneously separated. NMR analysis and DFT calculation suggest that a pair of cation and anion of [SO3H‐BMIm][OTf] could form three strong H‐bonds with an ether molecule, which catalyze the ether transformation via a cyclic oxonium intermediate. A series of O‐heterocycles including tetrahydrofurans, tetrahydropyrans, morpholines and dioxane can be obtained from their corresponding ethers in excellent yields (e.g. >99 %). This work opens an efficient and metal‐free way to produce O‐heterocycles from aliphatic ethers. [ABSTRACT FROM AUTHOR]

The fabrication of catalysts that can activate CO2 under ambient conditions is very interesting but challenging. Metal–organic hybrids (MOHs) have promising applications in catalysis, and their fabrication from renewable resources is very attractive. Herein, we report a simple protocol to fabricate metal–organic hybrids (MOHs) from chitosan, phytic acid and ZnCl2, obtaining mesoporous MOH-Zn possessing –OH, –NH2, and –PO4 groups. The resulting MOH-Zn shows excellent activity for CO2 activation and enables the cyclization of epoxides with CO2 to proceed under ambient conditions, affording a high turnover frequency of 7.8 h−1. The high performance of MOH-Zn originates from the synergistic effects among multi-functional sites in the catalysts. [ABSTRACT FROM AUTHOR]

Lithium-oxygen batteries with ultrahigh energy density have received considerable attention as of the future energy storage technologies. The development of effective electrocatalysts and a corresponding working mechanism during cycling are critically important for lithium-oxygen batteries. Here, a single cobalt atom electrocatalyst is synthesized for lithium-oxygen batteries by a polymer encapsulation strategy. The isolated moieties of single atom catalysts can effectively regulate the distribution of active sites to form micrometre-sized flower-like lithium peroxide and promote the decomposition of lithium peroxide by a one-electron pathway. The battery with single cobalt atoms can operate with high round-trip efficiency (86.2%) and long-term stability (218 days), which is superior to a commercial 5 wt% platinum/carbon catalyst. We reveal that the synergy between a single atom and the support endows the catalyst with excellent stability and durability. The promising results provide insights into the design of highly efficient catalysts for lithium-oxygen batteries and greatly expand the scope of future investigation. Li–O2 batteries represent one of the promising paths toward high energy density battery systems. Here the authors synthesize single atom Co electrocatalysts to regulate the formation and decomposition of the major discharge product Li2O2, realizing high round-trip efficiency and stability in a Li–O2 cell. [ABSTRACT FROM AUTHOR]

• Highly dispersed VO x with controlled structures were synthesized via ALD. • Only isolated monomeric VO x was formed for A-1VAl. • The polymerization extent was increased with increasing the ALD cycles from 3 to 8. • The isolated VO x is more active and more stable than the polymeric VO x for CO 2 -ODEB. • The bridging V O Al bond is the key active site for CO 2 -ODEB. Supported vanadium oxides are widely used as active catalysts for a number of oxidation and oxidative dehydrogenation reactions, and the understanding the structure-function relationship is of great importance for developing more efficient vanadium oxide catalysts. In this work, atomic layer deposition (ALD) was utilized to disperse sub-monolayer VO x over a commercial γ-Al 2 O 3 support. Characterization results indicate that highly dispersed VO x species with different structures were obtained by simply changing the number of ALD cycles. The vanadium oxides synthesized by performing 1 cycle of ALD were exclusively isolated monomeric VO x. With increasing the number of ALD cycles from 3 to 8, the polymeric VO x spices were formed, and the polymerization extent or domain size of VO x was increased. On the contrary, crystalline V 2 O 5 besides polymeric VO x was found if the number of ALD cycles was extended to 12. Catalytic performances of ALD VO x /γ-Al 2 O 3 were evaluated for the oxidative dehydrogenation of ethylbenzene with CO 2 (CO 2 -ODEB), and the isolated monomeric VO x species were found to be more active and more stable than the polymeric VO x species and crystalline V 2 O 5. By correlating the specific activity and the structural characteristics of ALD VO x /γ-Al 2 O 3 catalysts, the V O Al bonds were concluded as the key active sites for CO 2 -ODEB. [ABSTRACT FROM AUTHOR]

• The catalyst is prepared by one-step method. • Manganese doping is conducive to improving the electrocatalytic performance. • N-doping increases the electrical conductivity and promotes the transmission of electrons. • The catalysts exhibit high electrocatalytic activities for OER, ORR and Zn-air battery. In this work, several Mn-doped Co 2 P/N-doped carbon composite materials were facilely prepared through one-step carbonizing and phosphating treatments. The catalysts have exhibited high bifunctional catalytic activities for OER and ORR. Notably, the optimized catalyst Mn(0.1)-Co 2 P/NC exhibited high electrocatalytic activities for ORR (with onset/half-wave potential of 0.856/0.784 V vs. RHE, respectively) and OER (with an overpotential of 370 mV at 10 mA/cm2), which are very near to those of Pt/C (20%) and RuO 2 noble catalyst, respectively. When the Mn(0.1)-Co 2 P/NC was employed as air electrode catalyst for rechargeable Zn-air battery, the battery exhibited a high open-circuit voltage of 1.351 V, a stable discharge voltage of 1.08 V, a high round-trip efficiency of 47.3% and excellent stability for 100 cycles at 10 mA/cm2, which is superior to the one using Pt/C (20%) + RuO 2 as the air electrode catalyst. A series of Mn-doped Co 2 P/N-doped carbon composite materials were facilely prepared and used as the air cathode for rechargeable Zn-air battery. The optimized sample Mn(0.1)-Co 2 P/NC exhibited highly efficient catalytic activities for OER and ORR. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu 3 Pd 1 /SN exhibits a high performance for semihydrogenation of phenylacetylene. • Cu 3 Pd 1 /SN could activate phenylacetylene via C≡C → Nb π-bonded coordination. • The photogenerated electrons facilitate the production of active H. Bimetallic alloy of CuPd nanoclusters decorated SnNb 2 O 6 nanosheet (CuPd/SN) as a multifunctional photocatalyst has been constructed successfully. Compared with SN, CuPd/SN achieves an excellent performance for semihydrogenation of phenylacetylene under visible light irradiation. Especially, CuPd/SN with the Cu:Pd molar ratio of 3:1 exhibits the highest catalytic conversion efficiency for phenylacetylene (99.6%) with high selectivity of phenylethylene (99.4%). In situ FTIR result reveals that SN could activate phenylacetylene via a C≡C → Nb π-bonded coordination which improves the selectivity of phenylethylene. Experiment results indicate that atom Pd in alloy is responsible for dissociation H 2 , while Cu represses the overhydrogenation. Electrochemical measurements suggest that CuPd alloy on SN surface could greatly minimize the recombination of photogenerated electron − hole pairs. The separated electrons further facilitate the production of active H. Hydrogen spillover would transfer active H to Nb site for phenylacetylene semihydrogenation. Finally, a synergetic catalytic mechanism is deeply discussed at molecule scale. This work would provide a deep insight for designing a multifunctional photocatalyst. [ABSTRACT FROM AUTHOR]

Poly( N-vinylimidazole) (PVI) was grafted onto magnetic Fe3O4 nanoparticles through siloxane bonds to produce PVI-grafted Fe3O4 nanoparticles (shortened as Fe3O4- g-PVI). The amount of imidazolyl groups in Fe3O4- g-PVI was estimated to be 1.16 mmol/g by elemental analysis and thermal gravimetric analysis. The Fe3O4- g-PVI coordinated with Cu(II) to form the immobilized Cu(II)-PVI complex. The stoichiometric ratio between imidazolyl groups in Fe3O4- g-PVI and Cu(II) was found to be 4 and the complex formation constant ( K) was calculated to be 5.6 × 1014 mol−4 L4. The immobilized Cu(II)-PVI complex was employed to catalyze the oxidative polymerization of 2,6-dimethylphenol (DMP) in water and showed excellent CO/CC selectivity to form PPO. After polymerization, the immobilized Cu(II)-PVI complex catalyst was collected by an external magnetic field and reused in the next run with additional immobilized catalyst and copper ions. After three runs of oxidative polymerization of DMP, the recovery rate of the immobilized Cu(II)-PVI catalyst was above 95% and the yield of PPO maintained as high as 79.2% with the addition of supplementary catalysts. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple metal–organic framework-derivatised strategy was adopted to prepare Cu/Cu2O@NG materials. • Cu/Cu2O@NG-2 showed a good catalytic performance with a FE of 56 % and a current density of 19.0 mA/cm2 for C2–C3 products. • NG facilitated the dispersion of Cu/Cu2O particles, increased the catalytic active sites and enhance the stability. CO 2 is the main gas that causes the greenhouse effect, so electrochemical reduction of CO 2 can be regarded as a solution to alleviate the climate crisis. In this study, a simple metal–organic frameworks (MOFs)-derivatized strategy was adopted to prepare electrocatalyst, where MOF-199 and N-doped graphene (NG), as precursors, were electroreduced to obtain Cu/Cu 2 O@N-doped graphene (Cu/Cu 2 O@NG) materials for efficient CO 2 electroreduction to produce C 2 -C 3 products (ethylene, ethanol and n-propanol). A series of Cu/Cu 2 O@NG materials, especially Cu/Cu 2 O@NG-2 with a Faraday efficiency of 56 % and corresponding current density of 19.0 mA/cm2 for C 2 -C 3 products, showed a considerably better catalytic performance compared with the MOF-199-derived Cu/Cu 2 O material. This good performance was mainly attributed to the synergistic effect between the evenly dispersed Cu/Cu 2 O and NG, leading to good CO 2 adsorption capacity, rapid mass transfer and abundant active sites. [ABSTRACT FROM AUTHOR]

5-Hydroxymethylfurfural (HMF) derived from biomass can be converted to a variety of high-value chemicals. Transformation of glucose and fructose to HMF is the typical reactions involved in transformation of raw biomass to HMF. However, poor stability of heterogeneous solid acid and the side reactions of HMF consumption still is a challenge for the entitled reaction. In the present work, a strategy of catalyst with dual acid of Lewis acid and Brønsted acid combined with the biphasic solvent system of organic-aqueous salt is employed to design the effective catalytic system for the transformation of glucose and fructose to HMF. An SiO 2 -Zr-P heterogeneous solid acid with the dual acid sites was prepared by grafting of zirconium dioxide on silica followed by its phosphation. The surface grafted zirconium dioxide was transformed to the zirconium phosphate with the formula of Zr(HPO 4) 2 ·H 2 O. Both the Lewis acid and Brønsted acid of the SiO 2 -Zr-P are enhanced and their influences for the entitled reaction was investigated. The prepared catalyst was employed to catalyse the entitled reaction in the biphasic solvent of tetrahydrofuran-aqueous NaCl solvent, giving 99.9% yield of HMF for fructose and 75.2% yield of HMF for glucose. The catalyst showed good stability and can be applied for the catalytic transformation of various sugars to corresponding HMF and fufural with satisfied yield. [Display omitted] • The SiO 2 -Zr-P catalyst shows high efficiency for entitled reaction. • The heterogeneous catalyst has good stability during the reaction. • The present catalytic system has universality for converting various sugars. [ABSTRACT FROM AUTHOR]

We report a novel composite graphene oxide (GO)/NiFe 2 O 4 /TiO 2 nanorod arrays (NRAs) prepared by calcinating and dipping, TiO 2 NRAs were prepared via hydrothermal method. XRD, SEM, XPS, and PL, show that GO/NiFe 2 O 4 /TiO 2 NRAs have been successfully synthesized having enhanced photocatalytic performance. Furthermore, the optimal degradation conditions of unsymmetrical dimethylhydrazine (UDMH) using the catalyst were obtained by orthogonal and single-factor experiment. Moreover, the possible photocatalytic mechanism is briefly discussed; under visible light, electrons and holes excited from NiFe 2 O 4 can be effectively separated due to the band energy matching between NiFe 2 O 4 and TiO 2. In addition, photogenerated electrons can quickly migrate to GO owing to the conduction band, as the position of NiFe 2 O 4 is more negative than the Fermi level of GO. The electrons and holes were well separated so that they can efficiently participate in the degradation of UDMH, resulting in enhancement of photocatalytic activity. • AA novel composite catalyst GO/NiFe 2 O 4 /TiO 2 NRAs was prepared for the first time. • It exhibits enhanced photocatalytic activity in degradation of UDMH, due to the efficient separation of carriers. • The optimal degradation conditions of UDMH under this catalyst are also achieved. [ABSTRACT FROM AUTHOR]

• MgSO 4 /ZrO 2 with lewis acid and base sites were prepared. • 99 % of α-(trifluoromethyl) benzyl alcohol can be yield over MgSO 4 /ZrO 2 at room temperature. • The active sites on the surface of MgSO 4 /ZrO 2 were investigated by the adsorption/reaction heat with the microcalorimeter. • The reaction synergistical mechanism of lewis acid and base for the reaction was proposed. Trifluoromethylation is an important route to achieve the organic fluorinated compounds. In the present work, heterogeneous catalyst of MgSO 4 /ZrO 2 with Lewis base and acid was designed and prepared for the heterogeneous catalytic trifluoromethylation of aldehydes with (trifluoromethyl)trimethylsilane to the α -(trifluoromethyl)benzyl alcohol. The prepared catalyst was characterized to reveal its structure by XRD, FT-IR, Py-FTIR, Raman, XPS, NH 3 -TPD, CO 2 -TPD, and TGA. The heterogenous catalyst showed good catalytic performances with 99 % yield of α-(trifluoromethyl) benzyl alcohol at room temperature. The active sites on the surface of MgSO 4 /ZrO 2 were investigated by the adsorption/reaction heat with the microcalorimeter. The reaction mechanism was proposed. The heterogenous catalyst possessed good stability for the entitled reaction. In addition, it showed good universality for the trifluoromethylation of various benzaldehyde derivatives to the corresponding α -(trifluoromethyl) benzyl alcohol. [Display omitted] [ABSTRACT FROM AUTHOR]

• Lattice distortion of Mn 3 O 4 activated the surface-lattice oxygen species. • Abundant interface between Mn 3 O 4 and amorphous SmO x have been observed. • Catalytic CO oxidation activity of the composite catalysts was greatly enhanced. • Shielding effect of full outer-shell (5p66s2) of Sm3+ improved its H 2 O resistance. • SO 2 tolerance was doubled prolonged than that of the pristine Mn 3 O 4. Activation of lattice oxygen species in oxides is an important research topic for improving catalytic oxidation activity. Herein, we tuned the lattice distortion of Mn 3 O 4 spinel oxide via interfacing with amorphous samarium oxides, which would facilitate the activation of lattice oxygen. The crystalline Mn 3 O 4 dispersed uniformly on the amorphous SmO x with a large surface area, which builds abundant interfaces along with many active sites. The lattice distortion degree can be conveniently regulated by changing Sm amount and calcination temperature. The Sm 0.3 Mn (Sm/Mn molar ratio is 0.3, the calcination temperature is 400 °C) exhibited the optimal intrinsic activity for CO oxidation. Compared with the pristine Mn 3 O 4 , its TOF Mn increased by 60%, and the reaction rate in wet conditions (10 vol% H 2 O) was fourfold faster, superior to most reported MnO x oxide catalysts. Integrating with the various characterizations, the improvement of the intrinsic activity fundamentally originates from the rich reactive oxygen species in the lattice-distorted Mn 3 O 4. What's more, the Sm 0.3 Mn exhibited better water resistance and SO 2 tolerance. Electron characteristics and characterization results revealed that the full filling of the outer shell orbits of samarium protected the active sites at the interfaces from interacting with water. The weakened capacity for SO 2 oxidation decelerated the accumulation of sulfate species. This work provides new insights into the rational modulation of reactive oxygen species and developed a practical catalyst with efficient catalytic CO oxidation activity, and excellent water resistance and SO 2 tolerance. [ABSTRACT FROM AUTHOR]

The Ni based catalysts have been considered as promising candidates for the CO 2 reforming of CH 4 (CRM). However, they have suffered from two challenging issues of sintering and carbon accumulation. In order to overcome these drawbacks, a series of ordered mesoporous Ni-xMg-Al 2 O 3 catalysts (x was the mole ratio of Mg/(Mg + Al)) with different Mg contents were synthesized by an improved one-pot evaporation-induced self-assembly method. The effect of Mg on the physicochemical property and catalytic performance of Ni-xMg-Al 2 O 3 catalysts for CRM was investigated. The catalysts were characterized by XRD, H 2 -TPR, XPS, TEM, NH 3 -TPD, and N 2 adsorption-desorption at low temperature. The results showed that the introduction of Mg into the Ni–Al 2 O 3 maintained well the ordered mesoporous structure and enhanced the interaction between Ni and Al 2 O 3 , which could effectively restrict the thermal agglomeration of Ni nanoparticles. In addition, the acid sites were decreased with the introduction of Mg, which was beneficial for resistance to carbon accumulation, and then improving the CRM performance. Among Ni-xMg-Al 2 O 3 catalysts, Ni–3Mg–Al 2 O 3 presented the highest catalytic activity and stability. Under the conditions of 750 °C and GHSV = 32000 mL g−1 h−1, the conversion of CH 4 and CO 2 could reach 81.97% and 89.11% without deactivation for 20 h. • Ordered mesoporous Ni–Mg–Al 2 O 3 was prepared by the improved one-pot EISA. • The introduction of Mg into Ni–Al 2 O 3 enhanced the interaction between Ni and Al 2 O 3. • Ni–Mg–Al 2 O 3 suppressed the carbon accumulation during CO 2 reforming of CH 4. • The introduction of Mg improved the activity and stability of the catalyst. • Ordered mesoporous Ni–Mg–Al 2 O 3 was an efficient catalyst for CO 2 reforming of CH 4. [ABSTRACT FROM AUTHOR]

Selective catalytic reduction of NO x with ammonia (NH 3 -SCR) under the exposure of multiple poisons in fly ash remains a great challenging issue for environmental protection. Herein, the intelligently self-tunable defense effects of Ce(SO 4) 2 additive modification for the V 2 O 5 /CeO 2 catalyst with excellent resistance against K and Zn co-poisoning was originally illustrated. The Ce(SO 4) 2 additive could firstly act as an inhibitor to certainly restrain the electron transfer between V and Ce species to decrease the redox property, but the high NO x reduction efficiency of Ce(SO 4) 2 modified fresh catalyst could be maintained due to the enhancement of vanadium species polymerization and acidity. Unexpectedly, the Ce(SO 4) 2 additive would smartly translate to act as a promoter over the co-poisoned catalyst to effectively combine with poisons, thus releasing most active vanadium species to exhibit superior co-poisoning resistance to K and Zn. This work provides a novel self-tunable multi-poisoning-resistant strategy via acid additive modification for SCR catalysts. [Display omitted] • Ce(SO 4) 2 modified vanadia catalyst was obtained to fight K and Zn co-poisoning. • Ce(SO 4) 2 modification greatly improved NO x conversion and co-poisoning resistance. • Ce(SO 4) 2 was inhibitor to restrain electron transfer between active V and Ce sites. • Ce(SO 4) 2 translates to promoter to fix K and Zn poisons among poisoned catalysts. [ABSTRACT FROM AUTHOR]

Photothermal CO 2 oxidative dehydrogenation of propane (CO 2 -ODHP) is an environmentally friendly and sustainable route for propylene production and CO 2 utilization. In the present work, we developed a Pt-GaN/SrTiO 3 dual-functional catalyst to facilitate the reaction. The catalyst achieved propylene and CO yields of 1 mmol·g cat -1·h-1 and 1.2 mmol·g cat -1·h-1 under photothermal conditions at 320 °C, surpassing the performance of previously reported catalysts. Additionally, control experiments and in situ DRIFTS analyses corroborated that GaN and Pt were primarily responsible for the activation of C-H and C O bonds, respectively, and the photothermal route worked via a distinguished intermediate for CO 2 activation in contrast to the thermal route. DFT calculations supported the reaction route involving the coupling direct dehydrogenation of propane and reverse water-gas shift reaction. The present work shines a light on the design of photothermal catalysts with dual functions, particularly for the activation of CO 2 and light hydrocarbons. Additionally, it proposes a strategy to initiate high-temperature reactions at relatively lower temperatures. [Display omitted] • Pt-GaN/SrTiO 3 photothermally catalyzed CO 2 -ODHP for the first time. • GaN and Pt were primarily activations of C-H and C=O bonds respectively. • The DHP was driven by promoting the RWGS. • Different CO 2 intermediates were involved in thermal and photothermal reactions. [ABSTRACT FROM AUTHOR]

• An mn single-atom catalyst (SAC) with a coordination structure of Mn-O 4 anchored in nitrogen-doped graphitic carbon was developed for the first time. • The prepared catalyst exhibits a high CO faradic efficiency (FE) of 98.5 % and CO partial current density (j CO) of ∼9.77 mA cm−2 at a low overpotential of 0.32 V with 0.5 M KHCO 3 aqueous as the electrolyte in an H-type electrolytic cell, which outperforms current state-of-the-art nitrogen-coordinated mn SACs. • The nitrogen-free coordination environment significantly alters the electronic state and catalytic ability of the single mn site, which leads to the remarkable performance of CO 2 electroreduction. • Density functional theory (DFT) calculations reveal that the Mn-O 4 site significantly lowers the free energy of the COOH* formation compared to the conventional n atoms coordinated mn SACs, and thus facilitates the CO 2 -to-CO conversion. • A higher current density of 27.8 mA cm−2 with a FE CO of 93.8 % at 0.51 V overpotential is achieved in an ionic liquid (IL) electrolyte. Modulating the ordinary nitrogen coordination environment of single-atom catalysts (SACs) is a promising strategy for customizing their activity and selectivity in electrochemical reduction of CO 2 (CO 2 RR). However, less attention has been paid to developing Mn-SACs with nitrogen-free coordination environment for CO 2 electroreduction. Herein, we construct a Mn SAC with a coordination structure of Mn-O 4 anchored in nitrogen-doped graphitic carbon, which exhibits a 98.5 % of CO faradic efficiency (FE CO) with a high CO partial current density (j CO) of ∼9.77 mA cm−2 at a low overpotential of 0.32 V in an H-type electrolytic cell. Furthermore, a higher current density of 27.8 mA cm−2 with a FE CO of 93.8 % at 0.51 V overpotential was achieved in an ionic liquid (IL) electrolyte. Density functional theory (DFT) calculations reveal that the Mn-O 4 site significantly lowers the free energy of the COOH* formation compared to the conventional N atoms coordinated Mn SACs, and thus facilitates the CO 2 -to-CO conversion. [Display omitted] [ABSTRACT FROM AUTHOR]

It is highly desirable to regulate charge flow in photocatalyst for photocatalytic hydrogen reactions. In this study, a highly efficient sulfur vacancies- core–shell heterostructure photocatalyst (donoted as CdS-SV@CuS) was developed through surface modification of CdS-SV nanoparticles by CuS based on photoinduced interfacial charge transfer (IFCT). This novel photocatalyst with modulated charge transfer was prepared by hydrothermal treatment and subsequent cation-exchange reactions. The sulfur vacancies (SV) confined in CdS and the IFCT facilitate charge carriers efficient spatial separation. The optimized CdS-SV@CuS(5%) catalyst exhibited a remarkably higher H 2 production rate of 1654.53 umol/g/h, approximately 6.7 and 4.0 times than that of pure CdS and CdS-SV. The high photocatalytic performance is due to the rapid charge separation, intimate interactions between CdS-SV and CuS in the core–shell heterostructure. It is the first time adopts a facile method to construct metal sulfide core–shell structure for superior H 2 -production activity by IFCT. [Display omitted] To regulate the charge flow of the photocatalyst in photocatalytic hydrogen reactions is highly desirable. In this study, a highly efficient sulphur vacancies-CdS@CuS core–shell heterostructure photocatalyst (denoted CdS-SV@CuS) was developed through the surface modification of CdS-sulphur vacancies (SV) nanoparticles by CuS based on photoinduced interfacial charge transfer (IFCT). This novel photocatalyst with modulated charge transfer was prepared by hydrothermal treatment and subsequent cation-exchange reactions. The SV confined in CdS and the IFCT facilitate the charge carrier's efficient spatial separation. The optimized CdS-SV@CuS(5%) catalyst exhibited a remarkably higher H 2 production rate of 1654.53 μmol/g/h, approximately 6.7 and 4.0 times higher than those of pure CdS and CdS-SV, respectively. The high photocatalytic performance is attributed to the rapid charge separation, caused by the intimate interactions between CdS-SV and CuS in the core–shell heterostructure. This is the first time that a straightforward method is adopted to construct a metal sulphide core–shell structure for superior H 2 -production activity by IFCT. [ABSTRACT FROM AUTHOR]

[Display omitted] • Perovskite was used for asymmetric electrocarboxylation of aromatic ketones. • 85% yield and 95% enantiomeric excess were obtained on La 0.7 Sr 0.3 Fe 0.8 Ni 0.2 O 3. • The high-performance mainly results from the increased concentration of O2– and Fe4+. • La 0.7 Sr 0.3 Fe 0.8 Ni 0.2 O 3 has enhanced intrinsic electrochemical performance. The perovskite oxides La 0.7 Sr 0.3 Fe 0.8 B 0.2 O 3 (B = Ti, Mn, Co, Ni and Cu) synthesized by sol–gel method were used as cathodes and tested in asymmetric electrocarboxylation of aromatic ketones. The study showed the La 0.7 Sr 0.3 Fe 0.8 Ni 0.2 O 3 (La7Sr3Fe8Ni2) catalyst is more active for asymmetric electrocarboxylation of acetophenone with 95% enantiomeric excess and 85% yield. The high electrocatalytic activity is attributed mainly to several factors, including the increased amount of lattice oxygen and Fe4+ species on the surface of La7Sr3Fe8Ni2, enhanced electrochemically active surface area and faster electron transfer. Furthermore, La7Sr3Fe8Ni2 also exhibited remarkable stability and reusability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of flower-like hollow Ni 0.5 /xMgO-Al 2 O 3 catalysts were synthesized. • Ni 0.5 /xMgO-Al 2 O 3 catalysts have high specific surface area and thermostability. • Moderate Mg addition can promote the generation of spinels and then Ni x Mg y O. • More generation of spinels and Ni x Mg y O leads to stronger MSI and alkalinity. • Ni 0.5 /0.5MgO-Al 2 O 3 shows excellent DRM activity and high coking resistance. Dry reforming of methane (DRM) suffers catalysts deactivation due to severe coking. Ni/MgO-Al 2 O 3 is a promising system for DRM catalysts with high coking resistance, as the addition of MgO in Ni/Al 2 O 3 catalysts can improve the alkalinity of the support and enhance the metal-support interaction. However, so far the activity and stability of Ni/MgO-Al 2 O 3 is still unsatisfactory while the role of Mg addition remains unclear. In this paper, a series Ni 0.5 /xMgO-Al 2 O 3 catalysts with flower-like hollow sphere morphology and high surface area were synthesized via a facile hydrothermal method. Appropriate Mg addition promotes the formation of NiAl 2 O 4 while more Mg addition leads to the formation of Ni x Mg y O. Both cases can enhance the MSI of the catalysts without changing the morphology of the catalyst. More Mg addition also leads to stronger CO 2 adsorption via improving the alkalinity. Nevertheless, overdose of Mg results in weaker MSI and the blockage of Ni active sites. Ni 0.5 /0.5MgO-Al 2 O 3 with moderate Mg addition shows excellent activity (CH 4 ∼ 75 %, CO 2 ∼ 85 %) and stability (>100 h) at a high GHSV = 144000 ml/g cat ·h−1 and 800 °C with nearly no coking formation (<0.8 wt%). This work helps reveal the role of MgO addition in Ni/Al 2 O 3 systems and gives new insights into the design of DRM catalysts with high activity and stability. [ABSTRACT FROM AUTHOR]

The synthesis of aromatics via CO 2 hydrogenation is receiving an increasing attention. However, the direct conversion of CO 2 to a single aromatic product with high selectivity is very challenging. Herein, we report a synthesis of tetramethylbenzene(TeMB) on a tandem catalyst consisting of ZnZrO and hierarchical ZSM-11 zeolite, the selectivity of TeMB up to 79 % in aromatics is achieved while maintaining 76 % total aromatic selectivity. Uniform mesopores of ZSM-11 created with mixed TPAOH and NaOH organic-inorganic base are found to be responsible for the increased selectivity of aromatics and TeMB. Based on the acidic property of the catalyst, the increase of TeMB selectivity is attributed to the increase in the amount of the external BrØnsted acid which is increased with the external surface area of ZSM-11 zeolite. More BrØnsted acid on the external surface promotes the alkylation of low-carbon aromatics such as xylene, therefore increases the selectivity of TeMB. [Display omitted] • The ZnZrO/ZSM-11 tandem catalyst is used for the reaction of CO 2 hydrogenation. • ZnZrO/ZSM-11 is more conducive to the synthesis of TeMB compared with ZnZrO/ZSM-5. • TPAOH and NaOH mixed base promotes the formation of 2–10 nm uniform mesopores. • Uniform mesopores are beneficial for increasing the selectivity of aromatics and TeMB. • The increase in the amount of the external B acid increases the selectivity of TeMB. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnSA-MNC is a highly active and selective catalyst for electrochemical NO 3 −RR. • ZnSA-MNC is characterized by the atomic resolution HAADF-STEM. • ZnSA-MNC shows excellent NO 3 −RR performance. • DFT confirms that ZnSA coordinated with N atoms can interact with NO 3 − species. Electrochemical reduction of nitrate (NO 3 −) to ammonia (NH 3) in aqueous media is a double-advantage process, which can convert the main pollutant in water to the most useful chemical feedstocks. However, the design and development of highly effective and selective catalyst for NO 3 − reduction reaction (NO 3 −RR) is still challenging currently, as the NO 3 −RR contains multiple pathways and suppresses each other. Here, we demonstrate a highly active and selective Zn single atom supported microporous N -doped carbon catalyst, which was characterized by the atomic resolution high-angle annular dark field-scanning transmission electron microscopy, achieving excellent NO 3 −RR performance (NO 3 − conversion: 97.2 %; NH 3 selectivity: 94.9 %; NH 3 yield rate: ∼39,000 μg h−1 mg cat. −1; Faradaic efficiency: 94.8 %). Density functional theory calculations confirm that the atomically dispersed Zn atom coordinated with four N atoms has moderate interaction with NO 3 − species due to its positive charge. The reaction mechanism and potential determining step for NO 3 −RR on single Zn atom were further determined. This research provides an exciting new way for the rational design and development of single atom catalyst for advanced electrochemical applications. [ABSTRACT FROM AUTHOR]

• The high-energy ball mill decomposed palladium precursor and created oxygen vacancies on support. • The oxygen vacancies on TiO 2 (M) enhance the capacity for hydrogen storage of the optimal catalyst. • The light-induced energy can promote the phenol hydrogenation to cyclohexanone. An active catalyst Pd/TiO 2 (M) for phenol hydrogenation to cyclohexanone was constructed via a ball-milling process. This mechanical process avoids the thermal reduction in hydrogen atmosphere and creates oxygen vacancies on TiO 2 , which prevents the oxide support encapsulating active metal palladium due to the strong metal-support interaction(SMSI) but improves the catalytic performance of palladium. Under atmospheric hydrogen generated by electrolyzingwater, phenol can be hydrogenated to cyclohexanone selectively. Characterizations, control experiments and DFT calculations reveal that surface defective structures of Ti3+-O v can stabilize Pd nanoclusters and promote the formation of electron-rich Pd. This kind of electronic metal-support interaction facilitates the dissociative adsorption of phenol, so that Pd/TiO 2 (M) exhibits outstanding catalytic activity and selectivity for phenol hydrogenation to cyclohexanone. [Display omitted] [ABSTRACT FROM AUTHOR]

The rare earth metal Ce-doped cobalt ferrite samples Ce x Co 1− x Fe 2 O 4 ( x = 0.1, 0.3, 0.5) were prepared by the sol–gel autocombustion route. The as-prepared samples were characterized by X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, ICP–atomic emission spectroscopy, and N 2 physisorption. Their catalytic performance was evaluated in oxidation of styrene using hydrogen peroxide (30%) as oxidant. Compared with pristine CoFe 2 O 4 , the Ce-doped samples were found to be more efficient catalysts for the oxidation of styrene to benzaldehyde, with greatly enhanced catalytic performance. Especially, when Ce 0.3 Co 0.7 Fe 2 O 4 was used as catalyst, 90.3% styrene conversion and 91.5% selectivity for benzaldehyde were obtained at 90 °C for 9 h reaction. The catalyst can be magnetically separated easily for reuse, and no obvious loss of activity was observed when it was reused in five consecutive runs. [ABSTRACT FROM AUTHOR]

A series of ordered mesoporous carbons loaded with different contents of NiCo 2 O 4 (X-NiCo 2 O 4 /OMC) were synthesized via a facile hydrothermal method and proposed as a catalyst for electrocarboxylation of benzophenone for the first time. The materials were characterized by many measurements, which showed mesoporous structures with high surface area, good dispersion and stability. What's more, the materials exhibit good electrocatalytic performance due to its good ability to capture CO 2 and accelerate reaction rate, which brought by redox couples (Ni3+/Ni2+, Co3+/Co2+) and vacancy defects of NiCo 2 O 4. The optimal yield of methyl benzilate reaches 86% on 3-NiCo 2 O 4 /OMC. [Display omitted] • The use of NiCo 2 O 4 /OMC cathodes in electrocarboxylation of benzophenone with CO 2 was investigated for the first time. • The yield of methyl benzilate reaches 86% on optimal NiCo 2 O 4 /OMC material and electrolysis conditions. • The high-performance mainly results from the redox couples and vacancy defects of NiCo 2 O 4 /OMC. [ABSTRACT FROM AUTHOR]