Boosted electrochemical ammonia synthesis by high-percentage metallic transition metal dichalcogenide quantum dots.
Boosted electrochemical ammonia synthesis by high-percentage metallic transition metal dichalcogenide quantum dots.
复制标题
DOI：
10.1039/d0nr01409e
复制
发表时间：
2020-05
期刊：
影响因子：
6.7
通讯作者：
Jian Zhang;Chongyi Ling;W. Zang;Xiaoxia Li;Shaozhuan Huang;Xue Liang Li;D. Yan;Zongkui Kou
中科院分区：
文献类型：
--
作者：
Jian Zhang;Chongyi Ling;W. Zang;Xiaoxia Li;Shaozhuan Huang;Xue Liang Li;D. Yan;Zongkui Kou
电化学方法可以在环境条件下直接将N2转化为高附加值的NH3，被认为是传统哈伯-博世工艺的绿色和可持续的替代方案。然而，电化学氮还原反应（NRR）的缺点是氨产率低，超过了报道的电催化剂。在此，我们已经开发了一种通用策略来提高NRR性能，该策略由金属1 T相主导的过渡金属二硫属化物量子点（TMD QD）实现。令人印象深刻的是，所获得的MoSe 2 QD实现了340 μg mg-1催化剂·h-1的上级氨产率，具有优异的氨生成可持续性。实验和理论研究表明，MoSe 2量子点优异的催化活性主要来源于量子点的超小量子尺寸（高比表面积和高密度的活性边缘/缺陷位）和高比例的金属1 T相（1 T相上N2的吸附是自发的，1 T相上势能决定步骤的能垒很低）。最重要的是，我们的概念是通用的TMD材料（即，MoS 2、WSe 2、WS 2和NbSe 2），其与其它电催化剂相比也表现出大大提高的氨产率。
The electrochemical method can directly convert N2 into the high-value-added NH3 under ambient conditions and is considered to be a green and sustainable alternative to the traditional Haber-Bosch process. However, the electrochemical nitrogen reduction reaction (NRR) suffers from a low ammonia yield rate over the reported electrocatalysts. Herein, we have developed a general strategy to boost the NRR performance, enabled by the metallic 1T phase dominated transition metal dichalcogenide quantum dots (TMD QDs). Impressively, the obtained MoSe2 QDs achieved a superior ammonia yield rate of 340 μg mg-1 cat. h-1 with excellent ammonia generation sustainability. Experimental and theoretical studies revealed that the excellent catalytic activity of MoSe2 QDs mainly originates from the ultra-small quantized size (high surface area and high-density active edge/defect sites) and high-percentage metallic 1T phase (the N2 adsorption on the 1T phase is spontaneous, and the energy barrier of the potential determining step on the 1T phase is very low). Most importantly, our concept is universal for TMD materials (i.e., MoS2, WSe2, WS2 and NbSe2) that also exhibit a much-enhanced ammonia yield rate as compared to other electrocatalysts.