Palladium Nanoparticles Hardwired in Carbon Nanoreactors Enable Continually Increasing Electrocatalytic Activity During the Hydrogen Evolution Reaction.
Palladium Nanoparticles Hardwired in Carbon Nanoreactors Enable Continually Increasing Electrocatalytic Activity During the Hydrogen Evolution Reaction.
复制标题
DOI：
10.1002/cssc.202101236
复制
发表时间：
2021-11-19
期刊：
影响因子：
8.4
通讯作者：
中科院分区：
文献类型：
--
作者：
催化剂通常在运行过程中失去效力，在稳定活性金属中心以尽可能长地延长其功能寿命方面投入了大量精力。在这项研究中，钯纳米粒子（PdNP）内支撑的中空石墨化碳纳米纤维（GNF），指定为PdNP@GNF，反对这一趋势。PdNP@GNF在30000个反应循环中表现出连续增加的活性，当用作析氢反应（HER）中的电催化剂时。以交换电流密度表示的PdNP@GNF的活性始终高于活性炭（Pd/C），并且在10000次循环后，PdNP@GNF超过了铂/碳（Pt/C）的活性。PdNP@GNF非凡的耐久性和自我改进行为仅与钯纳米颗粒位置的独特性质有关，即在GNF内的石墨阶跃边缘处。透射电子显微镜成像结合光谱分析揭示了在电催化循环期间在石墨台阶边缘发生的一系列协调反应，其中一些弯曲的石墨表面打开以形成石墨烯层的堆叠，这些石墨烯层通过Pd-C键直接与Pd原子键合。这导致活性金属中心变得有效地硬连接到导电纳米反应器（GNF）中，使得能够容易地将电荷传输到催化中心/从催化中心传输，从而导致电催化剂的显著自我改善特性。 自我提升的空间：在析氢反应中，钯纳米粒子被限制在中空石墨化碳纳米纤维内，当用作电催化剂时，在超过30000次的反应循环中表现出显著增加的活性，超过了碳上的铂的活性。在操作过程中，钯被硬连线到打开的石墨台阶边缘中，使得能够容易地将电荷运输到催化中心/从催化中心运输，从而导致电催化剂的显著的自我改进特性。
Catalysts typically lose effectiveness during operation, with much effort invested in stabilising active metal centres to prolong their functional lifetime for as long as possible. In this study palladium nanoparticles (PdNP) supported inside hollow graphitised carbon nanofibers (GNF), designated as PdNP@GNF, opposed this trend. PdNP@GNF exhibited continuously increasing activity over 30000 reaction cycles when used as an electrocatalyst in the hydrogen evolution reaction (HER). The activity of PdNP@GNF, expressed as the exchange current density, was always higher than activated carbon (Pd/C), and after 10000 cycles PdNP@GNF surpassed the activity of platinum on carbon (Pt/C). The extraordinary durability and self‐improving behaviour of PdNP@GNF was solely related the unique nature of the location of the palladium nanoparticles, that is, at the graphitic step‐edges within the GNF. Transmission electron microscopy imaging combined with spectroscopic analysis revealed an orchestrated series of reactions occurring at the graphitic step‐edges during electrocatalytic cycling, in which some of the curved graphitic surfaces opened up to form a stack of graphene layers bonding directly with Pd atoms through Pd−C bonds. This resulted in the active metal centres becoming effectively hardwired into the electrically conducting nanoreactors (GNF), enabling facile charge transport to/from the catalytic centres resulting in the dramatic self‐improving characteristics of the electrocatalyst. Room for self‐improvement: Palladium nanoparticles confined inside hollow graphitised carbon nanofibers exhibit a remarkable increasing activity over 30000 reaction cycles when used as electrocatalyst in the hydrogen evolution reaction, surpassing the activity of platinum on carbon. During operation, palladium becomes hardwired into the graphitic step‐edges that open, enabling facile charge transport to/from the catalytic centres resulting in the dramatic self‐improving characteristics of the electrocatalyst.
登录
查看更多内容
影响因子：
3.9
作者：
Durst, Julien;Simon, Christoph;Gasteiger, Hubert A.
通讯作者：
Gasteiger, Hubert A.
影响因子：
3.9
作者：
BOCKRIS, JOM;POTTER, EC
通讯作者：
POTTER, EC
影响因子：
38.3
作者：
Chen, Zupeng;Vorobyeva, Evgeniya;Perez-Ramirez, Javier
通讯作者：
Perez-Ramirez, Javier
影响因子：
29.4
作者：
Cheng, Niancai;Banis, Mohammad Norouzi;Sun, Xueliang
通讯作者：
Sun, Xueliang
影响因子：
41.2
作者：
Cobo, Saioa;Heidkamp, Jonathan;Artero, Vincent
通讯作者：
Artero, Vincent