Two-dimensional ferroelectrics are important quantum materials which have found novel applications in nonvolatile memory devices, however the effects of their reversible polarization on chemical reactions and interactions with environments are rarely studied despite their importance. Here, based on first principles calculations, we found distinct gas adsorption behaviors on the surfaces of the ferroelectric In₂Se₃ layer and reversible gas capture and release controlled by a ferroelectric switch. We rationalize this novel phenomenon to the synergistic effect of electrostatic potential differences and electron transfer induced by band alignments between the frontier molecular orbitals of gas and the band-edge states of the substrate. Excitingly, the adsorption of paramagnetic gas molecules such as NO and NO₂ can induce surface magnetism, which is also sensitive to the ferroelectric polarization direction of In₂Se₃, indicating the application of In₂Se₃ as a threshold magnetic sensor/switch. Furthermore, it is suggested that two NO molecules ferromagnetically couple with each other, leading to the Curie temperature being polarization surface dependent and it can reach up to 50 K, and long-sought 2D molecule multiferroics. The ferroelectric controllable adsorption behavior and multiferroic feature of the molecules will find extensive application in gas capture, selective catalytic reduction and spintronic devices.

中文翻译：

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在In2Se3单层上使用铁电开关和2D分子多铁化合物进行可逆气体捕获

二维铁电体是重要的量子材料，已在非易失性存储设备中找到了新颖的应用，然而，尽管它们具有重要意义，但很少研究其可逆极化对化学反应和与环境的相互作用的影响。在此，根据第一性原理计算，我们发现在铁电In ₂ Se ₃表面上明显的气体吸附行为层和可逆气体的捕获和释放由铁电开关控制。我们将这种新现象合理化为由气体前沿分子轨道与基带边缘态之间的能带排列引起的静电势差和电子转移的协同效应。令人兴奋的，顺磁性气体分子如NO和NO的吸附₂可诱导表面磁性，这也是在铁电体的极化方向敏感₂硒₃，说明在应用₂硒₃作为阈值磁传感器/开关。此外，建议两个NO分子铁磁耦合，从而导致居里温度与极化表面有关，并且居里温度可高达50 K，并寻求2D分子多铁化合物。分子的铁电可控吸附行为和多铁性特征将在气体捕获，选择性催化还原和自旋电子器件中得到广泛应用。