Tackling the Inertness of CO2: Facile Activation and Electroreduction on the Metal-Free SiN4C4 Monolayer Sheet
Tackling the Inertness of CO2: Facile Activation and Electroreduction on the Metal-Free SiN4C4 Monolayer Sheet
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DOI：
10.1021/acs.jpcc.0c06076
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发表时间：
2020-08
影响因子：
3.7
通讯作者：
Lei Fang;Caiyun Zhang;Xinrui Cao;Z. Cao
中科院分区：
文献类型：
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作者：
Lei Fang;Caiyun Zhang;Xinrui Cao;Z. Cao
二氧化碳的捕获和活化在其催化转化为燃料和化学品的过程中起着至关重要的作用。在此，通过广泛的第一性原理计算和从头算分子动力学模拟，预测了一种具有分散的SiN₄位点的二维SiN₄C₄单层材料具有高稳定性以及解决二氧化碳惰性的非凡能力。二氧化碳在SiN₄C₄单层片上的化学吸附在热力学上是有利的，并且几乎没有势垒。这种在温和条件下的活化机制源于二氧化碳和SiN₄部分之间显著的电荷转移相互作用，其中近似平面的四配位硅作为一种强电子供体。外加电场的应用可能会显著影响二氧化碳的吸附和活化，而对甲烷、氮气和氢气没有影响，这可能为二氧化碳的分离和活化开辟一条高效且有前景的途径。此外，无金属的SiN₄C₄单层对二氧化碳电还原为甲酸、甲醇和甲烷表现出良好的活性，具有 -0.46 V的低极限电位。
Capture and activation
of CO2 play a crucial role in
its catalytic transformation into fuels and chemicals. Here a two-dimensional
SiN4C4 monolayer material with dispersed SiN4 sites was predicted to have high stability and unusual capability
to tackle the inertia of CO2 by extensive first-principles
calculations and ab initio molecular dynamics simulations. The chemical
adsorption of CO2 on the SiN4C4 monolayer
sheet is favorable thermodynamically and almost barrier free. Such
an activation mechanism under mild conditions comes from the remarkable
charge transfer interactions between CO2 and the SiN4 moiety, where an approximately planar tetracoordinate silicon
behaves as a strong electron donor. Application of an external electric
field may remarkably influence the adsorption and activation of CO2, while it has no effect on CH4, N2,
and H2, which may open up an efficient and promising avenue
for the separation and activation of CO2. Furthermore,
the metal-free SiN4C4 monolayer exhibits good
activity toward CO2 electroreduction to HCOOH, CH3OH, and CH4 with low limiting potentials of −0.46
V.