التفاصيل البيبلوغرافية
| العنوان: |
Operando analysis reveals potential-driven in situ formation of single-Fe-atom electrocatalysts for green production of ammonia. |
| المؤلفون: |
Fa Yang, Ping Song, Xin Ge, Yan Wang, Takao Gunji, Wei Zhang, Xiao Zhao, Weilin Xu |
| المصدر: |
Proceedings of the National Academy of Sciences of the United States of America; 6/20/2023, Vol. 120 Issue 25, p1-8, 55p |
| مصطلحات موضوعية: |
X-ray absorption spectra, ELECTROCATALYSTS, STRUCTURE-activity relationships, OPEN-circuit voltage, INFRARED absorption, GREEN products |
| مستخلص: |
As a sustainable approach for N2 fixation, electrocatalytic N2 reduction reaction (N2RR) to produce ammonia (NH3) is highly desirable with a precise understanding to the structure-activity relationship of electrocatalysts. Here, firstly, we obtain a novel carbon-supported oxygen-coordinated single-Fe-atom catalyst for highly efficient pro-duction of ammonia from electrocatalytic N2RR. Based on such new type of N2RR electrocatalyst, by combining operando X-ray absorption spectra (XAS) with density function theory calculation, we reveal significantly that the as-prepared active coordination structure undergoes a potential-driven two-step restructuring, firstly from FeSAO4(OH)1a to FeSAO4(OH)1a'(OH)1b with the adsorption of another -OH on FeSA at open-circuit potential (OCP) of 0.58 VRHE, and subsequently restructuring from FeSAO4(OH)1a'(OH)1b to FeSAO3(OH)1a" due to the breaking of one Fe-O bond and the dissociation of one --OH at working potentials for final electrocatalytic process of N2RR, thus revealing the first potential-induced in situ formation of the real electrocatalytic active sites to boost the conversion of N2 to NH3. Moreover, the key intermediate of Fe-NNHx was detected experimentally by both operando XAS and in situ attenuated total reflection--surface-enhanced infrared absorption spectra (ATR-SEIRAS), indicating the alternating mechanism followed by N2RR on such catalyst. The results indicate the necessity of considering the potential-induced restructuring of the active sites on all kinds of electrocatalysts for such as highly efficient ammonia production from N2RR. It also paves a new way for a precise understanding to the structure-activity relationship of a catalyst and helps the design of highly efficient catalysts. [ABSTRACT FROM AUTHOR] |
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| قاعدة البيانات: |
Complementary Index |
