College of Chemistry and Materials Engineering, Huaihua University, Huaihua 418008, China.
Hunan Engineering Research Center for Recycled Aluminum, Huaihua University, Huaihua 418008, China.
Molecules. 2023 Mar 27;28(7):2995. doi: 10.3390/molecules28072995.
Herein, we prepared PtCeO heterojunction nanocluster (HJNS) on multiwalled carbon nanotubes (MWCNTs) in deep eutectic solvents (DESs) which is a special class of ionic liquids. The catalyst was then heat-treated at 400 °C in N (refer to PtCeO/CNTs-400). The PtCeO/CNTs-400 catalyst showed remarkably improved electrocatalytic performance towards methanol oxidation reaction (MOR) (839.1 mA mg) compared to PtCeO/CNTs-500 (620.3 mA mg), PtCeO/CNTs-300 (459.2 mA mg), PtCeO/CNTs (641.6 mAmg) (the catalyst which has not been heat-treated) and commercial Pt/C (229.9 mAmg). Additionally, the PtCeO/CNTs-400 catalyst also showed better CO poisoning resistance (onset potential: 0.47 V) compared to PtCeO/CNTs (0.56 V) and commercial Pt/C (0.58 V). The improved performance of PtCeO/CNTs-400 catalyst is attributed to the addition of appropriate CeO, which changed the electronic state around the Pt atoms, lowered the d-band of Pt atoms, formed more Ce-O-Pt bonds acting as new active sites, affected the adsorption of toxic intermediates and weakened the dissolution of Pt; on the other hand, with the assistance of thermal treatment at 400 °C, the obtained PtCeO HJNS expose more new active sites at the interface between Pt and CeO to enhance the electrochemical active surface area (ECSA) and the dehydrogenation process of MOR. Thirdly, DES is beneficial to the increase of the effective component Pt(0) in the carbonization process. The study shows a new way to construct high-performance Pt-CeO catalyst for the direct methanol fuel cell (DMFC).
在此，我们在深共熔溶剂（DES）中制备了负载在多壁碳纳米管（MWCNTs）上的 PtCeO 异质结纳米团簇（HJNS），DES 是一类特殊的离子液体。然后将催化剂在 400°C 的 N 中进行热处理（称为 PtCeO/CNTs-400）。与 PtCeO/CNTs-500（620.3 mA mg）、PtCeO/CNTs-300（459.2 mA mg）、PtCeO/CNTs（未热处理的催化剂，641.6 mA mg）和商业 Pt/C（229.9 mA mg）相比，PtCeO/CNTs-400 催化剂对甲醇氧化反应（MOR）表现出显著提高的电催化性能（839.1 mA mg）。此外，与 PtCeO/CNTs（0.56 V）和商业 Pt/C（0.58 V）相比，PtCeO/CNTs-400 催化剂还表现出更好的 CO 中毒抗性（起始电位：0.47 V）。PtCeO/CNTs-400 催化剂性能的提高归因于添加了适量的 CeO，这改变了 Pt 原子周围的电子态，降低了 Pt 原子的 d 带，形成了更多的 Ce-O-Pt 键作为新的活性位，影响了有毒中间体的吸附并减弱了 Pt 的溶解；另一方面，在 400°C 的热处理的协助下，获得的 PtCeO HJNS 在 Pt 和 CeO 之间的界面上暴露出更多的新活性位，以增强电化学活性表面积（ECSA）和 MOR 的脱氢过程。第三，DES 有利于增加碳化过程中有效成分 Pt(0)的含量。该研究为直接甲醇燃料电池（DMFC）提供了构建高性能 Pt-CeO 催化剂的新途径。
