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[Display omitted] • Ti 2 Nb 10 O 29 cages were synthesized by self-sacrificing template method. • Ti 2 Nb 10 O 29 cages comprised of nanorod units exhibit perforated structure and big hollow center. • The special cage structure diminishes ion diffusion distance and relieves concentration polarization. • Lithium-ion battery with ultrahigh rate capability is achieved. Benefiting from large tunnel structure, zero strain feature, and excellent pseudocapacitive performance, Ti 2 Nb 10 O 29 was considered as a potential anode material for lithium-ion batteries (LIBs). Herein, Ti 2 Nb 10 O 29 cages comprised of nanorod units were elaborately designed. The mesoscopic structure could effectively shorten the ion diffusion pathway, and the big central electrolyte reservoir relieves the concentration polarization of electrolyte. Moreover, the perforated pore feature guarantees competent contact between electrolyte and framework. As the anode of LIBs, the mesoscopic Ti 2 Nb 10 O 29 cages deliver high reversible capacity (302.5 mAh/g) and rate capability (134.3 mAh/g at 30 A/g). This unique mesoscopic structure holds excellent potential for the electrode design of high-rate and long-life LIBs. [ABSTRACT FROM AUTHOR]

• Environmentally benign Cu-based catalysts are desirable for DMO hydrogenation. • Cu-Zn bimetallic catalysts with intimate metal contact are designed and tested. • Activity descriptor is reexamined and stability descriptor is unraveled. • High activity and excellent stability are achieved in the ethylene glycol production. The development of robust catalysts for selective hydrogenation of dimethyl oxalate (DMO) is key for the expansion of ethylene glycol (EG) production from C1 and renewable feedstocks. Copper-based catalysts promoted with Cr are industrially used, but it is desirable to develop more environmentally-benign alternatives. Silica-supported copper-zinc bimetallic catalysts featuring intimate metal contact are designed and used to establish the structure-performance relationships through combining in-depth characterizations with steady-state catalytic testing. Our study highlights: i) that the surface Cu0/Cu+ ratio is a reliable catalytic descriptor that determines the activity and selectivity, and ii) the importance of copper-zinc interface in stabilizing copper nanoparticles both under reduction and hydrogenation conditions. Controlled zinc doping allows fine tuning of these properties for the targeted reaction. Excellent performance has been achieved on the best-performing catalyst with >99.6% DMO conversion, >96.0% EG selectivity, and unprecedented stability of 800 h without catalyst deactivation, which represents a significant advance in the selective hydrogenations. [ABSTRACT FROM AUTHOR]

• Nitrogen and phosphorus codoped carbon-based catalyst was successfully prepared. • Catalysts with NP-C600 gave excellent activity and stability for acetylene hydrochlorination. • The conversion of C 2 H 2 over NP-C600 is almost identical to that over Au/C. • Phosphorus atoms bonded with nitrogen in a pyridine structure are the active sites for the best-performing NP-C600 catalyst. Catalyzed acetylene hydrochlorination for vinyl chloride monomer (VCM) production is of great industrial importance, as VCM is the precursor for polyvinyl chloride. Carbon-based materials have recently been proposed as environmentally friendly and cost-efficient substitutes for highly toxic mercuric chloride catalyst, which is currently used for VCM manufacture. However, their practical application has been limited because of their relatively low reactivity, due to the lack of efficient active sites. Structural engineering of carbon-based materials has been proved a powerful strategy for tuning their physical and chemical properties, which are directly related to their catalytic properties. Here we present a novel and highly active nitrogen- and phosphorus-codoped carbon-based catalyst prepared using 1-ethylsulfonate-3-methylimidazolium dihydrogen phosphate [ESO 3 HMim+H 2 PO 4 −] as a phosphorus source and 1-ethyl-3-methylimidazolium dicyanamide [EMim]+N(CN) 2 −] as a nitrogen source, which has shown unexpectedly high acetylene hydrochlorination activity with space-time yield comparable to that of some well-developed Au-based catalysts. Experimental observations in combination with density functional theory calculations demonstrated that phosphorus atoms bonded with nitrogen in the pyridine structure are the active sites for the best-performing NP-C600 catalyst. This work provides a promising method of structure tuning of carbon-based metal-free materials to effectively optimize their catalytic mechanism and applications. [ABSTRACT FROM AUTHOR]