Nickel oxide-based thin films and nanomaterials are a current focus of intense research efforts due to the broad range of end uses in a variety of applications. While the chemico-physical properties of bulk NiO crystals, characterized by a wide band gap (4.0–4.3 eV), antiferromagnetic ordering and p-type character, have been extensively studied, for NiO films/nanomaterials the microscopic-level relationships between the surface defect structure and electronic properties are far from being completely elucidated. In the present work, we show that, by using density functional theory with the Hubbard correction (DFT+U), –OH surface defects, almost ubiquitous on oxide surfaces, can directly influence the electronic structure of NiO(100) model slabs. Depending on the exact defect chemical structure and surface defect density, the energy gap of the –OH bearing NiO(100) system can be engineered, and its behaviour can be modulated from p-type to n-type. The insights provided herein may be of importance for the modulation of NiO nanosystem properties as a function of specific applications, an important issue for their eventual real-world utilization.

中文翻译：

---

–OH 表面缺陷对氧化镍薄膜电子和结构性能的影响


由于氧化镍基薄膜和纳米材料在各种应用中的最终用途广泛，因此是当前密集研究工作的重点。虽然以宽禁带 （4.0–4.3 eV）、反铁磁有序和 p 型特性为特征的块体 NiO 晶体的化学物理性质已得到广泛研究，但对于 NiO 薄膜/纳米材料，表面缺陷结构和电子性质之间的微观关系远未完全阐明。在本工作中，我们表明，通过使用密度泛函理论和哈伯德校正 （DFT+U），在氧化物表面上几乎无处不在的 –OH 表面缺陷可以直接影响 NiO（100） 模型板的电子结构。根据确切的缺陷化学结构和表面缺陷密度，可以设计 –OH 轴承 NiO（100） 系统的能隙，并且其行为可以从 p 型调制到 n 型。本文提供的见解对于作为特定应用的 NiO 纳米系统特性的调制可能具有重要意义，这是其最终实际使用的重要问题。