School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China.
Hirano Institute for Materials Innovation, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China.
ChemSusChem. 2017 Jul 21;10(14):2875-2879. doi: 10.1002/cssc.201700779. Epub 2017 Jun 26.
Oxygen vacancies can help to capture oxygen-containing species and act as active centers for oxygen evolution reaction (OER). Unfortunately, effective methods for generating a high amount of oxygen vacancies on the surface of various nanocatalysts are rather limited. Here, we described an effective way to generate oxygen-vacancy-rich surface of transition metal oxides, exemplified with Co O , simply by constructing highly coupled interface of ultrafine Co O nanocrystals and metallic Ti. Impressively, the amounts of oxygen vacancy on the surface of Co O /Ti surpassed the reported values of the Co O modified even under highly critical conditions. The Co O /Ti electrode could provide a current density of 23 mA cm at an OER overpotential of 570 mV, low Tafel slope, and excellent durability in neutral medium. Because of the formation of a large amount of oxygen vacancies as the active centers for OER on the surface, the TOF value of the Co O @Ti electrode was optimized to be 3238 h at an OER overpotential of 570 mV, which is 380 times that of the state-of-the-art non-noble nanocatalysts in the literature.
氧空位有助于捕获含氧物种，并作为氧析出反应 (OER) 的活性中心。不幸的是，在各种纳米催化剂表面上生成大量氧空位的有效方法相当有限。在这里，我们描述了一种在过渡金属氧化物表面生成富含氧空位的有效方法，以 CoO 为例，通过构建超细 CoO 纳米晶和金属 Ti 的高度耦合界面即可实现。令人印象深刻的是，即使在苛刻条件下，CoO/Ti 表面的氧空位数量也超过了报道的改性 CoO 的数值。CoO/Ti 电极在中性介质中提供了 570 mV 过电势下 23 mA cm 的电流密度、低塔菲尔斜率和出色的耐久性。由于表面上形成了大量的氧空位作为 OER 的活性中心，CoO@Ti 电极的 TOF 值在 570 mV 的过电势下优化为 3238 h，是文献中最先进的非贵金属纳米催化剂的 380 倍。
