[en] The use of fullerene [60] (C₆₀) as carbon support material for the dispersion of catalysts, which provides new ways to develop the advanced electrocatalyst materials for its distorted structure. In this article, polyaniline (PANI)-modified C₆₀ (abbreviated as PANI-C₆₀) is introduced, and the platinum–ruthenium alloy nanoparticles are successfully supported on PANI-C_60. According to the transmission electron microscopy measurements, the average particle size of the as-prepared nanoparticles dispersed on PANI-C₆₀ is 2.4 nm. Electrochemical studies reveal that the Pt-Ru/PANI-C₆₀ nanocomposites show excellent electrocatalytic activity toward methanol oxidation, showing that the PANI-C₆₀ may be a better potential candidate to be used as the supports of catalyst for electrochemical oxidation

[en] Non-equilibrium kinetic intermediates are usually preferentially generated instead of thermodynamic stable phases in the solid-state synthesis of layered oxides. Understanding the inherent complexity between thermodynamics and kinetics is important for designing high cationic ordering cathodes. Single-crystal strategy is an effective way to solve the intrinsic chemo-mechanical problems of Ni-rich cathodes. However, the synthesis of high-performance single-crystal is very challenging. Herein, the kinetic reaction path and the formation mechanism of non-equilibrium intermediates in the synthesis of single-crystal Co-free Ni-rich were explored. We demonstrate that the formation of non-equilibrium intermediate and the electrochemical-thermo-mechanical failure can be effectively inhibited by driving low-temperature topotactic lithiation. This work provides a basis for designing high-performance single-crystal Ni-rich layered oxides by regulating the defective structures. (© 2023 Wiley‐VCH GmbH)

[en] Highlights: → MWCNTs are used as the electrocatalyst support. → Sodium phthalate is used as an effective cross linker between MWCNTs and Pt ions. → Pt nanoparticles are monodispersed on the surface of the MWCNTs. → The catalyst shows superior catalytic activity and stability for methanol electrooxidation. - Abstract: Due to the inherent inertness of multi-wall carbon nanotubes (MWCNTs), complicated procedures are involved in the preparation of MWCNT-supported catalysts. In this paper, a facile and effective method is introduced to prepare Pt nanoparticles dispersed on the surface of purified MWCNTs. In this method, sodium phthalate (SP) is used as a special additive to function as an effective cross linker between MWCNTs and Pt ions, and ethylene glycol (EG) aqueous solution is used as an effective solvent. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) analyses reveal that the prepared face-centered cubic Pt nanoparticles with the average diameter of 2.2 nm are well dispersed on the surface of the MWCNTs. Cyclic voltammetry and chronoamperometry tests demonstrate that the Pt/MWCNTs catalyst obtained from typical experiment exhibits better catalytic activity and stability for methanol electrooxidation than the Pt catalyst supported on conventional acid-treated MWCNTs (AO-MWCNTs) and JM commercial 20% Pt/C catalyst.

[en] Highlights: • 3-D porous N-doped graphene was prepared using one-step silica template-free method. • High specific surface area of 920 m"2 g"−"1 was achieved for 3-D porous N-doped graphene. • Much higher ORR activity was observed for N-doped graphene than S-doped one in 0.1 M KOH. • The as-prepared catalyst gave a peak power density of 275 mW cm"−"2 as zinc–air battery cathode. - Abstract: Three-dimensional nanoporous nitrogen-doped graphene (3D-PNG) has been synthesized through a facial one-step synthesis method without additional silica template. The as-prepared 3D-PNGwas used as an electrocatalyst for the oxygen reduction reaction (ORR), which shows excellent electrochemistry performance, demonstrated by half-cell electrochemical evaluation in 0.1 M KOH including prominent ORR activity, four electron-selectivity and remarkable methanol poisoning stability compared to commercial 20%Pt/C catalyst. The physical and surface properties of 3D-PNG catalyst were characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and BET surface area analysis. The experiments show that 3D-PNG catalyst possesses super-large specific surface area reaching 920 m"2 g"−"1, which is superior to our most recently reported 3D-PNG synthesized by silica template (670 m"2 g"−"1) and other doped graphene catalysts in literature. When used for constructing a zinc–air battery cathode, such an 3D-PNG catalyst can give a discharge peak power density of 275 mW cm"−"2. All the results announce a unique procedure to product high-efficiency graphene-based non-noble metal catalyst materials for electrochemical energy devices including both fuel cells and metal–air batteries.

[en] Single crystalline flower-like Bi₂S₃ nanostructures were successfully synthesized via a simple, facile and green hydrothermal method, with the assistance of D-penicillamine. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), and found their morphologies mainly depend on the ratios of Bi³⁺ to D-penicillamine, as well as the reaction temperature and time. And the possible growth mechanism has been discussed in some detail. In addition, the as-prepared Bi₂S₃ nanoflowers show good hydrogen storage ability. This strategy can be potentially expanded to prepare other metal chalcogenides materials. - Graphical abstract: In this study, a simple and facile hydrothermal method was developed for the construction of single crystalline flower-like Bi₂S₃ nanostructures with the assistance of D-penicillamine. The as-prepared Bi₂S₃ nanoflowers show good hydrogen storage ability. • Single crystalline flower-like Bi₂S₃ nanostructures were synthesized • D-penicillamine played an important role in the nanostructures • The possible growth mechanism has been discussed • The as-prepared Bi₂S₃ nanoflowers show good hydrogen storage ability

[en] Highlights: • A series of morphology-controlled Fe-based MOFs are successfully prepared. • The competitive coordination and solvent effect play significant roles inregulating the morphologies of precursors. • The derivedFe2O3 products inherit themorphologies of their MOFs precursors and expose different active latticeplanes. • The CO-Fe2O3with high active facets exhibits better trifunctional performance than othermorphologic Fe2O3 products. Developing efficient trifunctional electrocatalysts with high activity and long durability is extraordinarily desirable. Metal-organic frameworks (MOFs) are ideal self-sacrificial templates, and their derived electrocatalysts are promising for the oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, Fe-based MOFs with well-aligned morphologies have been synthesized by elaborately tuning the competitive coordinated cations from diverse metal sources and solvent systems through a one-step solvothermal method. In this process, the competitive coordination with the metal sites between the ligands and the solvent molecules allows the feasibility to regulate the morphologies of these MOF precursors. After pyrolysis, the resulting Fe₂O₃ compounds not only inherit the morphologies of the precursors, but also expose different active lattice planes, producing disparate intrinsic active sites. Particularly, the concave octahedral (CO)-Fe₂O₃ with higher active facets and more accessible surface-active sites exhibits a superior electrocatalytic activity and stability for ORR, OER and HER compared with other morphologies and structures. This competitive coordination strategy paves an innovative and feasible pathway for morphology- and structure-controlled MOFs derivatives with tailored catalytic centers toward electrochemical energy storage and convention.

[en] To maximize the utilization of catalysts and thereby reduce the high price, a new strategy was developed to prepare highly dispersed Pt-SnO_x nanoparticles supported on 8-Hydroxyquinoline (HQ) functionalized multi-walled carbon nanotubes (MWCNTs). HQ functionalized MWCNTs (HQ-MWCNTs) provide an ideal support for improving the utilization of platinum-based catalysts, and the introduction of SnO_x to the catalyst prevents the CO poisoning effectively. The as-prepared catalysts are characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. It is found that the HQ functionalization process preserves the integrity and electronic structure of MWCNTs, and the resulting Pt-SnO_x particles are well dispersed on the HQ-MWCNTs with an average diameter of ca. 2.2 nm. Based on the electrochemical properties characterized by cyclic voltammetry and chronoamperometry, the Pt-SnO_x/HQ-MWCNTs catalyst displays better electrocatalytic activity and stability for the methanol oxidation. It is worth mentioning that the forward peak current density of Pt-SnO_x/HQ-MWCNTs catalyst is ca. 1.9 times of that of JM commercial 20% Pt/C catalyst, which makes it the preferable catalyst for direct methanol fuel cells.

[en] Highlights: • Layered B/N co-doped carbon is rationally designed by intercalator-guided strategy using water-soluble green copolymer. • Quasi-solid zinc ion hybrid supercapacitors established achieves a remarkable an energy density of 86.8 Wh kg⁻¹. • Efficient energy storage for this device is greatly attributed to structural merits of the unique cathode. -- Abstract: Zinc-ion hybrid supercapacitors (ZHSs), inheriting the merits from supercapacitors and many batteries, exhibit promise in energy storage technologies. However, they are bottlenecked by the sluggish diffusion of Zn²⁺, Zn dendrite growth and inadequate cathodes. Herein, newly designed layered B/N co-doped porous carbon (LDC) guided by the intercalator is proposed for the first time as cathode material for high-energy-power ZHSs to efficiently mitigate these issues. Associated with the multiple synergy of short mass/charge transfer pathway, fast kinetics and increased electroactivity endowed by the structurally engineered LDC, the quasi-solid Zn//gelatin/ZnSO₄ (gel)//LDC ZHS device exhibits intriguing Zn-storage capabilities, including exceptional energy/power density of 86.8 Wh kg⁻¹/12.2 kW kg⁻¹ in a relatively wide voltage window of 0.2–1.8 V, long service life of 6500 cycles at 5 A g⁻¹ and low self-discharge. Moreover, smart watch and LED indicator can be driven well by this device. The present results highlight the facile and efficient synthesis of a layered carbon-based cathode material, significantly contributing to the rapid development of eco-friendly and scalable Zn-based hybrid energy devices.

[en] Graphical abstract: Ppy hollow nanospheres with uniform size have been successfully prepared and employed as the supports for Pd nanoparticles with smaller particle size and better dispersion. Electrochemical measurements demonstrate that the obtained Pd/H-ppy exhibits good electrocatalytic activity and stability for ethanol electrooxidation. - Highlights: • Ppy hollow nanospheres support provides new ways to develop catalyst materials as a result of its distorted structure and large surface area. • Ppy hollow nanospheres with uniform size have been successfully prepared through chemical oxidative polymerization of pyrrole in the presence of PS microspheres. • Pa nanoparticles have been successfully assembled on the surface of hollow ppy nanospheres. • Pd/H-ppy exhibits good electrocatalytic activity and stability for ethanol electrooxidation. - Abstract: A facile and low-cost preparation of Pd nanoparticles on the surface of hollow polypyrrole (ppy) nanospheres was introduced in this paper through solvothermal reaction. Herein, uniform polystyrene (PS) microspheres as sacrificial templates were rapidly prepared through a emulsion polymerization method, and then the hollow ppy nanospheres were obtained through chemical oxidative polymerization of pyrrole in the presence of PS microspheres. According to X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements, the novel Pd nanoparticles are well-dispersed on the surface of hollow ppy nanospheres with a relatively narrow particle size distribution. The diameters of hollow ppy nanospheres range from 240 to 280 nm, and the average shell thickness is about 15 nm. Electrochemical analysis results indicate that the as-prepared Pd nanoparticles on the surface of hollow ppy nanospheres (Pd/H-ppy) exhibit good electrocatalytic activity and stability for ethanol electrooxidation

[en] Due to the inherent inertness of carbon nanotubes (CNTs), one of the most significant challenges in the preparation of CNT-supported catalysts is achieving a uniform deposition of nanoparticles on the surface of the nanotubes. In this paper, we report on the preparation and characterization of Pd nanoparticles supported on untreated multi-walled carbon nanotubes (MWCNTs), synthesized in the presence of glutamate. The results of Raman spectroscopy revealed that this synthetic procedure does not have a detrimental effect on the surface structure of MWCNTs. Transmission electron microscopy (TEM) measurements indicated that the dispersion of Pd nanoparticles on untreated-MWCNTs in the presence of glutamate were uniform, and a narrow particle size was observed. X-ray diffraction (XRD) patterns indicated that the Pd/MWCNT catalyst possessed a face-centered cubic crystal structure. Cyclic voltammetry and chronoamperometry tests demonstrated that the obtained Pd/MWCNT catalyst displayed superior electrocatalytic activity and stability in formic acid oxidation, as compared to both a Pd/MWCNT catalyst synthesized without glutamate and a Pd catalyst on acid-oxidized MWCNTs, under otherwise identical experimental conditions. These results indicate that the catalyst developed in this study is a superior candidate for direct formic acid fuel cells (DFAFCs).