Regulating the coordination environment of transition-metal based materials in the axial direction with heteroatoms has shown great potential in boosting the oxygen reduction reaction (ORR). The coordination configuration and the regulation method are pivotal and elusive. Here, we report a combined strategy of matrix-activization and controlled-induction to modify the CoN₄ site by axial coordination of Co–S (Co₁N₄-S₁), which was validated by the aberration-corrected electron microscopy and X-ray absorption fine structure analysis. The optimal Co₁N₄-S₁ exhibits an excellent alkaline ORR activity, according to the half-wave potential (0.897 V vs. reversible hydrogen electrode (RHE)), Tafel slope (24.67 mV/dec), and kinetic current density. Moreover, the Co₁N₄-S₁ based Zn-air battery displays a high power density of 187.55 mW/cm² and an outstanding charge–discharge cycling stability for 160 h, demonstrating the promising application potential. Theoretical calculations indicate that the better regulation of CoN₄ on electronic structure and thus the highly efficient ORR performance can be achieved by axial Co–S.

Photocatalytic oxidation has been widely employed in organic synthesis, by virtue of the green, mild and simple reaction conditions as well as high selectivity. Introducing oxygen vacancies (OVs) with proper concentrations into the photocatalysts has been proven as an effective strategy to boost the catalytic performances. However, the currently used treatment method under high temperature at reducing atmosphere inevitably introduces a large number of OVs at the interior of the catalyst and serving as the recombination centers of carriers. To address this issue, here we develop a facile solvothermal process to prepare ultrathin BiOBr nanosheets with rich surface OVs. This method effectively decreases the bulk of the material and the ratio of interior OVs, rendering most of the OVs exposed on the surfaces which act as exposed catalytic sites and enhance the separation of carriers, therefore significantly elevates the photocatalytic performances. For the photo-oxidation reaction of secondary amines, under the conditions of visible light, ambient temperature and atmosphere, the BiOBr nanosheets featuring rich surface OVs deliver a doubled conversion compared to those with low OV concentrations, and a high selectivity of 99%, a high stability as the performance shows no reduction after 5 times of circular reaction.

Catalytic hydrogenation is an important process in the chemical industry. Traditional catalysts require the effective cleavage of hydrogen molecules on the metal-catalyst surface, which is difficult to achieve with non-noble metal catalysts. In this work, we report a new hydrogenation method based on water/proton reduction, which is completely different from the catalytic cleavage of hydrogen molecules. Active hydrogen species and photo-generated electrons can be directly applied to the hydrogenation process with Cu_1.94S-Zn_0.23Cd_0.77S semiconductor heterojunction nanorods. Nitrobenzene, with a variety of substituent groups, can be efficiently reduced to the corresponding aniline without the addition of hydrogen gas. This is a novel and direct pathway for hydrogenation using non-noble metal catalysts.

RuCu nanocages and core–shell Cu@Ru nanocrystals with ultrathin Ru shells were first synthesized by a one-pot modified galvanic replacement reaction. The construction of bimetallic nanocrystals with fully exposed precious atoms and a high surface area effectively realizes the concept of high atom-efficiency. Compared with the monometallic Ru/C catalyst, both the RuCu nanocages and Cu@Ru core–shell catalysts supported on commercial carbon show superior catalytic performance for the regioselective hydrogenation of quinoline toward 1, 2, 3, 4-tetrahydroquinoline. RuCu nanocages exhibit the highest activity, achieving up to 99.6% conversion of quinoline and 100% selectivity toward 1, 2, 3, 4-tetrahydroquinoline.

We have exploited a new and distinctive combination method that "disperses" elemental Pd into CuS nanoplates. Pd was successfully dispersed by means of the concomitant transformation of CuS into an amorphous sulfide, which formed an intimate metal–sulfide contact via cation exchange and underwent a subsequent reduction. A series of such Pd-dispersed CuS hetero-nanoplates were synthesized with tailored proportions and compositions. By efficient utilization of noble metal atoms and stable anchored active sites, the optimal catalytic performance for the semihydrogenation of phenylacetylene, a probe reaction, was achieved with high selectivity, activity, and stability. We believe that the synthetic strategy described in our study is a feasible means of developing effective metal–sulfide catalysts for organic reactions.

A novel two-phase approach towards the corrosion of PtNi₁₀ nanoctahedra has been developed. In this strategy, the active component of Ni in oil-soluble PtNi₁₀ nanoctahedra which resided in the upper toluene phase, suffered from etching and was then transferred into a lower aqueous phase with coordination by ethylenediaminetetraacetate (EDTA). Due to the existence of the phase-transfer interface promoted by EDTA, the corrosion reaction proceeded at an accelerated rate under the mild conditions. Specifically, the resultant products of octahedral Pt₄Ni nanoframes were successfully fabricated for the first time, and PtNi₄ porous octahedra could be obtained when the dosage of EDTA-2Na was reduced. After a systematic study of this two-phase system, a "synergetic corrosion" mechanism is proposed to account for the formation of octahedral Pt₄Ni nanoframes, involving contributions from many species (i.e., O₂, H₂O, H⁺, OAm, and EDTA^4-). As a result of the fascinating three-dimensional geometry of Pt₄Ni nanoframes and PtNi₄ porous octahedra, both of the corroded nanocrystals showed superior activity over the pristine PtNi₁₀ nanoctahedra for ethanol electrooxidation in alkaline media and hydrogenation of nitrobenzene.

Lithium iron phosphate (LiFePO₄) is a potential high efficiency cathode material for lithium ion batteries, but the low electronic conductivity and single diffusion channel for lithium ions require good particle size and shape control during the synthesis of this material. In this paper, six LiFePO₄ nanocrystals with different size and shape have been successfully synthesized in ethylene glycol. The addition sequence Fe-PO₄-Li helps to form LiFePO₄ nanocrystals with mostly {010} faces exposed, and increasing the amount of LiOH leads to a decrease in particle size. The electrochemical performance of the six distinct LiFePO₄ particles show that the most promising LiFePO₄ nanocrystals either have predominant {010} face exposure or high specific area, with little iron(Ⅱ) oxidation.

[020]-oriented tin sulfide nanobelts with a length/thickness ratio of 100 have been synthesized by a facile hydrothermal method without any surfactants, and the nanobelts have shown good strain-accommodating properties as well as good electrochemical performance as the anode for Li-ion batteries. The formation of the nanobelts results from a precipitation–dissolution–transformation mechanism, and the [020] oriented growth can be ascribed to the {010} facet family having the lowest atomic density. In particular, SnS shows clear Li–Sn alloying/de-alloying reversible reactions in the potential range 0.1–1.0 V. Based on galvanostatic measurements and electrochemical impedance spectroscopy, SnS nanobelts have shown impressive rate performance. The post-cycled SnS nanobelts were completely transformed into metallic tin, and preserved the one-dimensional structure due to their flexibility which accommodates the large volumetric expansion.