TY - JOUR
T1 - Molybdenum Based 2D Conductive Metal–Organic Frameworks as Efficient Single-atom Electrocatalysts for N2 Reduction
T2 - A Density Functional Theory Study
AU - Sun, Yongxiu
AU - Shi, Wenwu
AU - Sun, Mengxuan
AU - Fang, Qisheng
AU - Ren, Xiaohe
AU - Yan, Yijun
AU - Gan, Ziwei
AU - Fu, Yongqing
AU - Elmarakbi, Ahmed
AU - Li, Zhijie
AU - Wang, Zhiguo
N1 - Funding information: This work was supported by International Exchange Grant (IEC/NSFC/201078) through the National Natural Science Foundation of China and Royal Society UK.
PY - 2023/3/3
Y1 - 2023/3/3
N2 - Electrocatalytic nitrogen reduction reaction (NRR) is a sustainable and eco-friendly process to generate ammonia (NH3). However, there are significant challenges including low catalytic performance, instability, and poor selectivity, which hinder its rapid development. Herein, a series of two-dimensional (2D) conductive metal-organic frameworks (i.e., TM3(HHTT)2, TM = Sc, Ti, V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu and Zn) are investigated as single atom catalysts (SACs) for NRR process by the density functional theory (DFT). The obtained results of Gibbs free energies of adsorption for N2, *NNH, *NH3, which are commonly used as activity descriptors to screen the effectiveness of catalysts, show that the Mo3(HHTT)2 monolayer (among all the TM3(HHTT)2 ones) can activate N≡N bonds, stabilize the adsorbed *NNH, and achieve the desorption of NH3. The Mo3(HHTT)2 monolayer also exhibits an excellent structural stability (with values of Ef = -2.96 eV and Udiss = 1.28 V). N2 can be effectively reduced into NH3 on the Mo3(HHTT)2 monolayer with a low limiting potential of -0.60 V along the distal pathway. Furthermore, the σ-donation and π* backdonation of N2 adsorbed onto the Mo3(HHTT)2 monolayer indicates an excellent electrical conductivity of Mo3(HHTT)2, which is beneficial for the effective electron transfer during the NRR process. Furthermore, the Mo3(HHTT)2 monolayer exhibits considerable selectivity for the NRR process over the hydrogen evolution reaction. Our study proved that this 2D c-MOFs carrying TM of the Mo3(HHTT)2 monolayer can be used as a promising catalyst for nitrogen fixation.
AB - Electrocatalytic nitrogen reduction reaction (NRR) is a sustainable and eco-friendly process to generate ammonia (NH3). However, there are significant challenges including low catalytic performance, instability, and poor selectivity, which hinder its rapid development. Herein, a series of two-dimensional (2D) conductive metal-organic frameworks (i.e., TM3(HHTT)2, TM = Sc, Ti, V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu and Zn) are investigated as single atom catalysts (SACs) for NRR process by the density functional theory (DFT). The obtained results of Gibbs free energies of adsorption for N2, *NNH, *NH3, which are commonly used as activity descriptors to screen the effectiveness of catalysts, show that the Mo3(HHTT)2 monolayer (among all the TM3(HHTT)2 ones) can activate N≡N bonds, stabilize the adsorbed *NNH, and achieve the desorption of NH3. The Mo3(HHTT)2 monolayer also exhibits an excellent structural stability (with values of Ef = -2.96 eV and Udiss = 1.28 V). N2 can be effectively reduced into NH3 on the Mo3(HHTT)2 monolayer with a low limiting potential of -0.60 V along the distal pathway. Furthermore, the σ-donation and π* backdonation of N2 adsorbed onto the Mo3(HHTT)2 monolayer indicates an excellent electrical conductivity of Mo3(HHTT)2, which is beneficial for the effective electron transfer during the NRR process. Furthermore, the Mo3(HHTT)2 monolayer exhibits considerable selectivity for the NRR process over the hydrogen evolution reaction. Our study proved that this 2D c-MOFs carrying TM of the Mo3(HHTT)2 monolayer can be used as a promising catalyst for nitrogen fixation.
KW - single-atom catalysts
KW - metal-organic frameworks
KW - density functional theory
KW - nitrogen reduction reaction
U2 - 10.1016/j.ijhydene.2023.02.039
DO - 10.1016/j.ijhydene.2023.02.039
M3 - Article
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
SN - 0360-3199
ER -