The electron-deficient property of the atoms in functional materials endow them with tunable adsorption and catalysis effects on polysulfides, thus improving the performance of lithium–sulfur batteries. In this work, Li2B4O7 nanoparticles, which have abundant electron deficiencies derived from the [BO3] Lewis acid units, were uniformly cladded in the carbon nanofibers (LBO–CNF) and employed as interlayers for Li–S batteries. This functionalized interlayer expressed a high adsorption energy of ∼3.6 eV for polysulfides (e.g., Li2S6 and Li2S4) and effectively suppressed the polysulfides' shuttle behavior, delivering a high reversible capacity of 1242.6 mA h g−1 at 0.2C and good cycling performance with a low fading rate of 0.068% per cycle at 1C, thus effectually inhibiting the phenomenon of self-discharge. Besides, the lithiation reaction kinetics was also effectively enhanced, enhancing the rate performance of the battery to 644 mA h g−1 at 5C. This work provides a new strategy to enhance the electrochemical performance of Li–S batteries by applying the compounds of electronic-deficiency B-species and functionalized carbon.
Wei Guijuan,Zhao Xixia,An Changhua,Liu Junxue,Wang Zhaojie,Du Kun,Zhang Jun
Clean Pt nanoclusters with a diameter of 1.0–2.4 nm, supported on reduced graphene oxide (rGO) nanosheets, were successfully synthesized by simple in situ thermolysis of a Pt-carbonyl complex. The supported Pt nanoclusters are in an electron-deficient state because of the electron transfer between the nanoclusters and the rGO sheets. The as-prepared Pt-1 nm/rGO shows high catalytic activity for the 100% selective hydrogenation of nitrobenzene, with the turnover frequency (TOF) reaching 975.4 h −1 at 25°C and 1 atm. This number is higher than the previously reported value for the heterogeneously catalyzed hydrogenation of nitrobenzene. The proposed process follows a direct hydrogenation mechanism, as is revealed by the analyses of the intermediate products. This work presents a facile and effective synthetic approach for achieving highly efficient nanocatalysts, and can be extended to obtain other metal catalysts with ultra-small sizes and excellent performance.
危险品化学品经营许可证（带存储）