Tetragonal-phase Pr2CuO4 nanosheets with a thickness of about 60 nm were synthesized using the coordination compound methods (CCMs), then used as highly efficient selective adsorbent towards malachite green (MG) in aqueous solutions. The Pr2CuO4 samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectrum (DRS), and standard Brunauer-Emmett-Teller (BET) methods. The maximum adsorption capacity (Qm) of as-prepared samples was determined by adsorption isotherms with different adsorbent doses (m) of 0.03-0.07 g at 298, 318, and 338 K based on the Langmuir model. When m < 0.03 g or > 0.07 g, effects of systemic mass loss and particle aggregation were discussed on the data deviation from the Langmuir model at 298 K. Based on the hydrogen bond and coordination bond, a possible mechanism of selective adsorption of MG by Pr2CuO4 is proposed, which was further verified by the adsorption experiments of CuO and Pr2O3 towards MG and competing-ion experiments. Finally, the theoretic studies were performed at DFT level to reveal the possible adsorption process.

中文翻译：

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Pr2CuO4纳米片的受控合成与选择性吸附性能：机理的讨论。

使用配位化合物方法（CCM）合成了厚度约为60 nm的四方相Pr2CuO4纳米片，然后将其用作对孔雀石绿（MG）的高效选择性吸附剂。使用X射线衍射（XRD），扫描电子显微镜（SEM），高分辨率透射电子显微镜（HRTEM），X射线光电子能谱（XPS），UV-Vis漫反射光谱（DRS）对Pr2CuO4样品进行表征和标准的Brunauer-Emmett-Teller（BET）方法。根据Langmuir模型，通过在298、318和338 K下使用0.03-0.07 g不同吸附剂剂量（m）的吸附等温线确定所制备样品的最大吸附容量（Qm）。当m <0.03 g或> 0.07 g时，讨论了在298 K时系统质量损失和粒子聚集对Langmuir模型数据偏离的影响。基于氢键和配位键，提出了Pr2CuO4选择性吸附MG的可能机理，并通过进一步验证。 CuO和Pr2O3对MG的吸附实验及竞争离子实验。最后，在DFT水平进行了理论研究，以揭示可能的吸附过程。