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Co‐based metal–organic frameworks (MOFs) as electrocatalysts for two‐electron oxygen reduction reaction (2e− ORR) are highly promising for H2O2 production, but suffer from the intrinsic activity‐selectivity trade‐off. Herein, we report a ZnCo bimetal‐triazole framework (ZnCo‐MTF) as high‐efficiency 2e− ORR electrocatalysts. The experimental and theoretical results demonstrate that the coordination between 1,2,3‐triazole and Co increases the antibonding‐orbital occupancy on the Co−N bond, promoting the activation of Co center. Besides, the adjacent Zn−Co sites on 1,2,3‐triazole enable an asymmetric "side‐on" adsorption mode of O2, favoring the reduction of O2 molecules and desorption of OOH* intermediate. By virtue of the unique ligand effect, the ZnCo‐MTF exhibits a 2e− ORR selectivity of ≈100 %, onset potential of 0.614 V and H2O2 production rate of 5.55 mol gcat−1 h−1, superior to the state‐of‐the‐art zeolite imidazole frameworks. Our work paves the way for the design of 2e− ORR electrocatalysts with desirable coordination and electronic structure. [ABSTRACT FROM AUTHOR]

Co‐based metal–organic frameworks (MOFs) as electrocatalysts for two‐electron oxygen reduction reaction (2e− ORR) are highly promising for H2O2 production, but suffer from the intrinsic activity‐selectivity trade‐off. Herein, we report a ZnCo bimetal‐triazole framework (ZnCo‐MTF) as high‐efficiency 2e− ORR electrocatalysts. The experimental and theoretical results demonstrate that the coordination between 1,2,3‐triazole and Co increases the antibonding‐orbital occupancy on the Co−N bond, promoting the activation of Co center. Besides, the adjacent Zn−Co sites on 1,2,3‐triazole enable an asymmetric "side‐on" adsorption mode of O2, favoring the reduction of O2 molecules and desorption of OOH* intermediate. By virtue of the unique ligand effect, the ZnCo‐MTF exhibits a 2e− ORR selectivity of ≈100 %, onset potential of 0.614 V and H2O2 production rate of 5.55 mol gcat−1 h−1, superior to the state‐of‐the‐art zeolite imidazole frameworks. Our work paves the way for the design of 2e− ORR electrocatalysts with desirable coordination and electronic structure. [ABSTRACT FROM AUTHOR]

Multinucleon transfer reactions are currently a powerful way to synthesize neutron-rich nuclei. To explore the effect of nucleus deformation and mirror nucleus shell correction energy in the nucleus mass model on the calculation of multinucleon transfer reaction cross sections in the dinuclear system (DNS) model, three macroscopic microscopic mass models are selected and the transfer reaction cross sections are calculated for 136Xe+208Pb and 64Ni+238U by improved DNS model+GEMINI++, respectively. The mirror nucleus shell correction energy does not improve the accuracy of the cross section of the transfer reaction. The introduction of a different dependence of the Coulomb and surface energy on the deformation can improve the calculation of the transfer reaction cross section when the projectile and target nuclei are deformed nuclei. [ABSTRACT FROM AUTHOR]

Hierarchical zeolites show great promise in green chemical and petrochemical processes, but their syntheses usually involve the use of nitrogen-/halogen-containing templates whose removal from the as-synthesized zeolites via calcination inevitably leads to serious environmental pollution, high energy consumption and sometimes destruction of zeolite frameworks. We report an eco-friendly and acid-degradable polymer denoted as PK3 as a multifunctional template to synthesize single-crystal hierarchical zeolites. It is shown that by strongly interacting with zeolite aluminosilicate gel precursors, PK3 acts as a structure-directing agent for the nucleation and crystallization of the amorphous gel into protozeolite crystals, and via its adsorption on the surfaces of protozeolite crystals, PK3 greatly inhibits their growth and thereby results in the formation of zeolitic nanocrystals. Furthermore, these thermodynamically unstable nanocrystals encapsulating PK3 spontaneously aggregate, then align in an oriented manner, and at last ripen, leading to the formation of single-crystal zeolite particles with interconnected mesopores. Importantly, the removal of PK3 from the as-synthesized zeolites can be achieved by a simple acid treatment. Thanks to these unique characteristics of PK3, a nitrogen-/halogen-free and combustion-free route is successfully achieved for synthesizing hierarchical MFI, MOR and GME zeolites. Moreover, the synthesized MFI zeolite exhibits superior catalytic activity in cracking low-density polyethylene. [ABSTRACT FROM AUTHOR]

A series of NiMo/FDU-12 catalysts with tunable pore diameters and mesostructures have been controllably synthesized by adjusting the synthetic hydrothermal temperature and applied for the hydrodesulfurization of dibenzothiophene and its derivative. The state-of-the-art electron tomography revealed that the pore sizes of FDU-12 supports were enlarged with the increase in the hydrothermal temperature and the mesostructures were transformed from ordered cage-type pores to locally disordered channels. Meanwhile, the MoS2 morphology altered from small straight bar to semibending arc to spherical shape and finally to larger straight bar with the change of support structures. Among them, FDU-12 hydrothermally treated at 150 °C possessed appropriate pore diameter and connected pore structure and was favorable for the formation of highly active MoS2 with curved morphology; thus, its corresponding catalyst exhibited the best HDS activity. Furthermore, it was indicated that the isomerization pathway could be significantly improved for HDS of 4,6-dimethyldibenzothiophene after the addition of aluminum, which was expected to be applied to the removal of the macromolecular sulfur compounds. Our study sheds lights on the relationship between support effect, active sites morphology and HDS performance, and also provides a guidance for the development of highly active HDS catalysts. [ABSTRACT FROM AUTHOR]