TY - JOUR
T1 - Superior Charge Transport in Ni-Diamine Conductive MOFs
AU - Wang, Jiande
AU - Chen, Tianyang
AU - Jeon, Mingyu
AU - Oppenheim, Julius J.
AU - Tan, Bowen
AU - Kim, Jihan
AU - Dincă, Mircea
N1 - Publisher Copyright:
© 2024 American Chemical Society.
PY - 2024/7/24
Y1 - 2024/7/24
N2 - Two-dimensional conductive metal-organic frameworks (2D cMOFs) are an emerging class of crystalline van der Waals layered materials with tunable porosity and high electrical conductivity. They have been used in a variety of applications, such as energy storage and conversion, chemiresistive sensing, and quantum information. Although designing new conductive 2D cMOFs and studying their composition/structure-property relationships have attracted significant attention, there are still very few examples of 2D cMOFs that exhibit room-temperature electrical conductivity above 1 S cm-1, the value exhibited by activated carbon, a well-known porous and conductive material that serves in myriad applications. When such high conductivities are achieved, Ni-diamine linkages are often involved, yet Ni-diamine MOFs remain difficult to access. Here, we report two new 2D cMOFs made through ortho-diamine connections: M3(HITT)2 (M = Ni, Cu; HITT = 2,3,7,8,12,13-hexaiminotetraazanaphthotetraphene). The electrical conductivity of Ni3(HITT)2 reaches 4.5 S cm-1 at 298 K, whereas the conductivity of Cu3(HITT)2 spans from 0.05 (2Cu+Cu2+) to 10-6 (3Cu2+) upon air oxidation, much lower than that of Ni3(HITT)2. Spectroscopic analysis reveals that Ni3(HITT)2 exhibits significantly stronger in-plane π-d conjugation and higher density of charge carriers compared to Cu3(HITT)2, accounting for the higher electrical conductivity of Ni3(HITT)2. Cu2+/Cu+ mixed valency modulates the energy level and carrier density of Cu3(HITT)2, allowing for a variation of electrical conductivity over 4 orders of magnitude. This work provides a deeper understanding of the influence of metal nodes on electrical conductivity and confirms ortho-diamine linkers as privileged among ligands for 2D cMOFs.
AB - Two-dimensional conductive metal-organic frameworks (2D cMOFs) are an emerging class of crystalline van der Waals layered materials with tunable porosity and high electrical conductivity. They have been used in a variety of applications, such as energy storage and conversion, chemiresistive sensing, and quantum information. Although designing new conductive 2D cMOFs and studying their composition/structure-property relationships have attracted significant attention, there are still very few examples of 2D cMOFs that exhibit room-temperature electrical conductivity above 1 S cm-1, the value exhibited by activated carbon, a well-known porous and conductive material that serves in myriad applications. When such high conductivities are achieved, Ni-diamine linkages are often involved, yet Ni-diamine MOFs remain difficult to access. Here, we report two new 2D cMOFs made through ortho-diamine connections: M3(HITT)2 (M = Ni, Cu; HITT = 2,3,7,8,12,13-hexaiminotetraazanaphthotetraphene). The electrical conductivity of Ni3(HITT)2 reaches 4.5 S cm-1 at 298 K, whereas the conductivity of Cu3(HITT)2 spans from 0.05 (2Cu+Cu2+) to 10-6 (3Cu2+) upon air oxidation, much lower than that of Ni3(HITT)2. Spectroscopic analysis reveals that Ni3(HITT)2 exhibits significantly stronger in-plane π-d conjugation and higher density of charge carriers compared to Cu3(HITT)2, accounting for the higher electrical conductivity of Ni3(HITT)2. Cu2+/Cu+ mixed valency modulates the energy level and carrier density of Cu3(HITT)2, allowing for a variation of electrical conductivity over 4 orders of magnitude. This work provides a deeper understanding of the influence of metal nodes on electrical conductivity and confirms ortho-diamine linkers as privileged among ligands for 2D cMOFs.
UR - http://www.scopus.com/inward/record.url?scp=85199422785&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85199422785&partnerID=8YFLogxK
U2 - 10.1021/jacs.4c06935
DO - 10.1021/jacs.4c06935
M3 - Article
C2 - 39007301
AN - SCOPUS:85199422785
SN - 0002-7863
VL - 146
SP - 20500
EP - 20507
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 29
ER -