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Hierarchical zeolites are highly‐desired catalysts in the petrochemical industry due to their shorter diffusion length, faster diffusion rate, and better accessibility to active acid sites compared with conventional zeolites. Herein, we report a simple amino‐acid‐assisted method to synthesize urchin‐like hollow hierarchical FER zeolites with abundant mesopores and macroporous inner cavities. An amino acid (i. e. L‐lysine) is used to facilitate the agglomeration of primary gel nanoparticles. The preferential nucleation and crystal growth at the external surfaces together with the lagged crystallization of the inner core of the agglomerates results in the formation of hollow inner cavities after the exhaustion of interior materials. Thanks to the unique hierarchical structure and more accessible acid sites, the hollow hierarchical FER zeolite exhibits improved catalytic performance over the conventional one in the skeletal isomerization of 1‐butene to isobutene. [ABSTRACT FROM AUTHOR]

Zeolites with uniform micropores are important shape‐selective catalysts. However, the external acid sites of zeolites have a negative impact on shape‐selective catalysis, and the microporosity may lead to serious diffusion limitation. Herein, we report on the direct synthesis of hierarchical hollow STW‐type zeolite single crystals with a siliceous exterior. In an alkalinous fluoride medium, the nucleation of highly siliceous STW zeolites takes place first, and the nanocrystals are preferentially aligned on the outer surface of the gel agglomerates to grow into single crystalline shells upon crystallization. The lagged crystallization of the internal Al‐rich amorphous gels onto the inner surface of nanocrystalline zeolite shells leads to the formation of hollow cavities in the core of the zeolite crystals. The hollow zeolite single crystals possess a low‐to‐high aluminum gradient from the surface to the core, resulting in an intrinsic inert external surface, and exhibit superior catalytic performance in toluene methylation reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • A facile co-precipitation method is used to prepare catalysts with particles confined in cheap MOF. After calcination, more catalytic active sites could be exposed, which greatly improves the performance of the catalyst. • Compared with other methods, the co-precipitation method is simple, low-cost, and can better control the metal loading. At the same time, the problem of easy agglomeration of Cu nanoparticles and easy phase separation of Cu and ZnO at high temperature could be alleviated greatly. • The as-prepared Cu/ZnO x /ZrO 2 catalyst shows much better performance for CO 2 hydrogenation to methanol than the commercialized catalyst and catalyst prepared by double solvents method. The ternary Cu/ZnO/Al 2 O 3 catalyst is usually employed for producing methanol from syngas (CO/CO 2 /H 2) or from CO 2 hydrogenation in industry. However, this catalyst often suffers from the aggregation of Cu nanoparticles and the phase separation of Cu and ZnO. In this work, a highly efficient and stable catalyst (Cu/ZnO x /ZrO 2) for CO 2 hydrogenation to methanol is prepared via co-precipitation method with UiO-66 as structural template. Cu/Zn is effectively combined and encapsulated in the channels of UiO-66, which avoids the aggregation of metal particles. The ZrO 2 support derived from UiO-66 enhances the interaction between the support and Cu/Zn, and thus improves the catalytic performance significantly. This catalyst shows a high space–time yield of 216.7 g (MeOH) ·kg (cat) −1·h−1 at 260 °C, 4 MPa and GHSV = 12000 h−1. Furthermore, the catalyst shows good stability over a period of 50 h on stream. The performance of Cu/ZnO x /ZrO 2 is much better than that of commercial catalysts and most of catalysts previously reported. [ABSTRACT FROM AUTHOR]

• The Orange II degradation efficiency attained to 98.9% within 15 min. • OH played an important role in the Cu 2 O(SO 4)-Fe9/H 2 O 2 Fenton-like process. • The degradation rate constant of Cu 2 O(SO 4)-Fe9 is 9.33 and 4.07 times of Cu 2 O(SO 4) and α-Fe 2 O 3 , respectively. • Orange II degradation is conducted through destruction of conjugated structures and mineralization. Hematite (α-Fe 2 O 3), as one of Fenton reagents, is widely investigated for the treatment of wastewater in the field of advanced oxidation processes (AOPs). Considering the fast charge carrier recombination of hematite (α-Fe 2 O 3), we have successfully synthesized a novel and high active heterogeneous Fenton catalyst α-Fe 2 O 3 /Cu 2 O(SO 4) for the degradation of organic pollutants. The results show that the as-obtained Cu 2 O(SO 4)-Fe9 composite exhibits excellent degradation properties of Orange II. 98.9% degradation rate was achieved for 100 mL of 50 mg/L Orange II solution in the condition of 0.3 g/L Cu 2 O(SO 4)-Fe9 catalyst, 3 mM H 2 O 2 and pH = 3.5. The degradation rate constants of Cu 2 O(SO 4)-Fe9 in the photo-Fenton-like system are 9.33 and 4.07 times of Cu 2 O(SO 4) and α-Fe 2 O 3 , respectively. In addition, the mechanism and pathway for the degradation of Orange II were proposed. The scheme of combining copper-based oxysulfate Cu 2 O(SO 4) with hematite (α-Fe 2 O 3) could improve the efficiency of charge carrier separation, which will further enhance the catalytic activity and expand its application in water purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • The right amount of cobalt ions could induce the formation of Fe 1-x S. • 100 mL orange II solution (30 mg/L) was degraded to 99.9% within 15 min. • OH and h+ played an important role in the photo-Fenton-like process. • FeS 2 -Fe 1-x S exhibited excellent stability and high catalytic degradation activity for other dyes. It is a challenge to develop heterogeneous Fenton-like catalysts with excellent performance and stability in the field of wastewater treatment. In this work, the FeS 2 -Fe 1-x S heterostructure catalyst was prepared by solvothermal method through adding cobalt element to change the particle nucleation process and inhibit the transformation process of pyrrhotite (Fe 1-x S) phase to pyrite (FeS 2) phase. Then, a series of experiments were devised to clarify the catalytic activity of FeS 2 -Fe 1-x S heterostructure. The degradation experiments exhibited that 99.9% degradation efficiency was achieved for 30 mg/L orange II solution within 15 min at the conditions of 0.2 g/L FeS 2 -Fe 1-x S, 2 mM H 2 O 2 and pH = 3.0. In addition, the reusability of the FeS 2 -Fe 1-x S catalyst was also investigated and the result displayed that degradation efficiency of orange II can reach 95.2% after eight cycles. The degradation of orange II was enhanced by Fenton reaction between FeS 2 -Fe 1-x S and dissolved oxygen, which could smoothly release Fe2+ and Fe3+ for the activation of H 2 O 2 to produce more hydroxyl radicals. Finally, the degradation pathway of orange II was proposed by detecting intermediates produced in FeS 2 -Fe 1-x S/H 2 O 2 photo-Fenton-like system by liquid chromatography-mass spectrometry (LC-MS). In short, FeS 2 -Fe 1-x S is a promising catalyst for removing the organic pollutants from solutions. [ABSTRACT FROM AUTHOR]

Abstract: Well-dispersed Fe0.3Co0.7/rGO nanocatalysts have been synthesized utilizing the two-step reduction method and successfully employed in the hydrolysis of ammonia borane (NH3BH3 AB) at room temperature. The mass percent of the supported Fe0.3Co0.7 nanoparticles (NPs) on graphene (rGO) sheets can reach to the maximum value of 50 wt%. The as-synthesized catalysts exerted satisfying activity and reusability for the hydrolytic dehydrogenation of AB at 298 K, especially for the specimen of 50 wt% Fe0.3Co0.7/rGO NPs. The catalytic hydrolysis reaction was rapidly completed within 1 min. [Copyright &y& Elsevier]

Abstract: Composite catalysts Fe0.3Co0.7-doped carbon aerogel have been in situ synthesized by chemical reduction method and successfully employed in the hydrolysis of NH3BH3 (AB) at room temperature. The mass percent of the doped Fe0.3Co0.7 alloys can reach to the maximum value of 40 wt%. The prepared catalysts exhibit excellent catalytic activity, especially for the specimen of 40 wt% Fe0.3Co0.7/C, which shows high catalytic activity and long durability. Its maximum hydrogen generation rate is as high as 13,695.6 ml min−1 g−1 at 298 K and the activation energy is only 20.83 kJ mol−1. Besides, this catalyst possesses preferable cycling stability at room temperature. The low cost, high catalytic activity and enhanced cycling stability can make it have a bright future in the application field of fuel chemistry. [Copyright &y& Elsevier]

A mixture of commercial NaAlH4 and 2 wt.% of nanocrystalline TiN is subjected to ball milling (stainless steel vessel, 450 rpm, 1 h, Ar atmosphere). [ABSTRACT FROM AUTHOR]