CAS Key Labratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, 100190 Beijing, China; College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Institute of Molecular and Nano Science, Shandong Normal University, Jinan 250014, China.
CAS Key Labratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, 100190 Beijing, China; Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
J Colloid Interface Sci. 2018 Mar 15;514:507-516. doi: 10.1016/j.jcis.2017.12.039. Epub 2017 Dec 23.
The application of nanohybrids based on polyoxomolybdates, reduced graphene oxide (rGO) and/or metal nanoparticles (NPs) high-performance electrode materials in electrocatalysis and energy storage devices is promising but still limited due to the complexity and the cost of the synthesis. Here we introduce a simple polyoxomolybdate, [MoO(OH)(HO)(CO)] (MoS), as reducing and stabilizing agent for the facile and one-pot syntheses of large quantity of highly stable MoS/rGO and MoS/Au NPs nanohybrids in aqueous solution without any catalyst or toxic co-solvent. They were characterized by various physical techniques and electrochemistry which confirm strong interaction between MoS and rGO sheets. We also used DFT calculations to investigate the affinity between MoS or its neutral form with graphene. The adsorption energy for the most stable configuration is -1.97 eV, indicating a strong adsorption process of MoS, which can also be confirmed by the distance (3.04 Å) and the charge transfer (0.86 e) between MoS and graphene. These observations are also consistent with the electrochemical results which underscore the excellent redox properties and high stability of MoS/rGO. Importantly, the MoS/rGO nanohybrids are excellent noble metal-free electrocatalysts for hydrogen peroxide reduction with high sensitivity, large detection range and low detection limit. Finally, the preliminary tests reveal that the electrode materials based on MoS/rGO and a low-cost carbon cloth (CC) composite MoS/rGO/CC may have a potential for an application in energy storage as performant and flexible supercapacitor, showing specific capacitance as high as 870 F g at 10 mV s and excellent stability after 5000 cycles.
基于多酸、还原氧化石墨烯(rGO)和/或金属纳米粒子(NPs)的纳米杂化材料在电催化和储能器件中的应用具有很大的潜力，但由于其合成的复杂性和成本限制，目前的应用仍然有限。在这里，我们介绍一种简单的多酸[MoO(OH)(HO)(CO)] (MoS)，它可以作为还原剂和稳定剂，用于在水溶液中简便、一锅法合成大量高稳定性的 MoS/rGO 和 MoS/Au NPs 纳米杂化物，而无需使用任何催化剂或有毒共溶剂。通过各种物理技术和电化学方法对其进行了表征，证实了 MoS 和 rGO 片之间存在强烈的相互作用。我们还使用 DFT 计算来研究 MoS 或其中性形式与石墨烯之间的亲和力。最稳定构型的吸附能为-1.97 eV，表明 MoS 的吸附过程很强，这也可以通过 MoS 和石墨烯之间的距离(3.04 Å)和电荷转移(0.86 e)来证实。这些观察结果也与电化学结果一致，突出了 MoS/rGO 的优异氧化还原性能和高稳定性。重要的是，MoS/rGO 纳米杂化物是用于过氧化氢还原的优异的无贵金属电催化剂，具有高灵敏度、大检测范围和低检测限。最后，初步测试表明，基于 MoS/rGO 的电极材料和低成本的碳纤维布(CC)复合材料 MoS/rGO/CC 可能具有作为高性能和灵活的超级电容器的储能应用潜力，在 10 mV s 时表现出高达 870 F g 的比电容和 5000 次循环后的优异稳定性。
