TY - JOUR
T1 - Metalloporphyrin-Linked Mercurated Graphynes for Ultrastable CO2 Electroreduction to CO with Nearly 100% Selectivity at a Current Density of 1.2 A cm-2
AU - Fang, Mingwei
AU - Xu, Linli
AU - Zhang, Hongyang
AU - Zhu, Ying
AU - Wong, Wai Yeung
N1 - Funding Information:
The work is supported by the National Natural Science Foundation of China (51872013, 52073009, 52011530190, 21905241, 52073242, 51672019), the National Key Research and Development Program of China (2017YFA0206902), and the 111 Project (B14009). W.-Y.W. and L.X. are grateful for financial support from the Science, Technology, and Innovation Committee of Shenzhen Municipality (JCYJ20180507183413211), the Hong Kong Research Grants Council (PolyU 15307321), the RGC Senior Research Fellowship Scheme (SRFS2021-5S01), the Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and Devices (GDSTC No. 2019B121205001), the Hong Kong Polytechnic University (1-ZE1C, 1-BD64), Research Institute for Smart Energy (CDAQ), and Miss Clarea Au for the Endowed Professorship in Energy (847S).
Publisher Copyright:
© 2022 American Chemical Society. All rights reserved.
PY - 2022/8/24
Y1 - 2022/8/24
N2 - The electrochemical reduction reaction of carbon dioxide (CO2RR) to the desired feedstocks with a high faradaic efficiency (FE) and high stability at a high current density is of great importance but challenging owing to its poor electrochemical stability and competition with the hydrogen evolution reaction (HER). Guided by theoretical calculations, herein, a series of novel metalloporphyrin-linked mercurated graphynes (Hg-MTPP) were designed as electrocatalysts for CO2RR, since the mercurated graphyne blocks induce a high HER overpotential. Notably, Hg-CoTPP was synthesized and produced a maximum CO FE of 95.6% at -0.76 V (vs reversible hydrogen electrode (RHE)) in an H-type cell, and a CO FE of 91.2% even at -1.26 V (vs RHE), due to a great suppression of HER. The Hg-CoTPP combined with N-doped graphene (Hg-CoTPP/NG) was able to achieve a high CO FE of nearly 100% at a current density of 1.2 A cm-2 and particularly a ground-breaking stability of over 360 h at around 420 mA cm-2 in a flow-type cell. Further experimental and computational results revealed that the mercurated graphyne of Hg-CoTPP brings a high HER overpotential and tunes the d-band electronic states of the metal center that make the d-band center closer to the Fermi level, thus enhancing the bonding of *COOH intermediates on Hg-CoTPP. The introduction of NG could shorten the Co-N coordination bonds, which enhances electron transfer to the metal center to lower the energy barrier for *COOH. Our results illustrated that Hg-MTPP could serve as a new class of two-dimensional (2D) materials and provide a design concept for developing efficient electrocatalysts for CO2RR in commercial applications.
AB - The electrochemical reduction reaction of carbon dioxide (CO2RR) to the desired feedstocks with a high faradaic efficiency (FE) and high stability at a high current density is of great importance but challenging owing to its poor electrochemical stability and competition with the hydrogen evolution reaction (HER). Guided by theoretical calculations, herein, a series of novel metalloporphyrin-linked mercurated graphynes (Hg-MTPP) were designed as electrocatalysts for CO2RR, since the mercurated graphyne blocks induce a high HER overpotential. Notably, Hg-CoTPP was synthesized and produced a maximum CO FE of 95.6% at -0.76 V (vs reversible hydrogen electrode (RHE)) in an H-type cell, and a CO FE of 91.2% even at -1.26 V (vs RHE), due to a great suppression of HER. The Hg-CoTPP combined with N-doped graphene (Hg-CoTPP/NG) was able to achieve a high CO FE of nearly 100% at a current density of 1.2 A cm-2 and particularly a ground-breaking stability of over 360 h at around 420 mA cm-2 in a flow-type cell. Further experimental and computational results revealed that the mercurated graphyne of Hg-CoTPP brings a high HER overpotential and tunes the d-band electronic states of the metal center that make the d-band center closer to the Fermi level, thus enhancing the bonding of *COOH intermediates on Hg-CoTPP. The introduction of NG could shorten the Co-N coordination bonds, which enhances electron transfer to the metal center to lower the energy barrier for *COOH. Our results illustrated that Hg-MTPP could serve as a new class of two-dimensional (2D) materials and provide a design concept for developing efficient electrocatalysts for CO2RR in commercial applications.
UR - http://www.scopus.com/inward/record.url?scp=85137124139&partnerID=8YFLogxK
U2 - 10.1021/jacs.2c05059
DO - 10.1021/jacs.2c05059
M3 - Journal article
C2 - 35947444
AN - SCOPUS:85137124139
SN - 0002-7863
VL - 144
SP - 15143
EP - 15154
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 33
ER -