The recent advancement of semiconductor devices to the near-atomic scale necessitated the development of atomic layer processing methods, including molecular layer deposition (MLD). This gas-phase deposition technique creates semipermeable polymer films with precise control of composition and thickness. Herein, MLD was used to produce thin-film composite reverse osmosis membranes. Aromatic polyamide films as thin as 0.5 nm were applied to NF270 nanofiltration membranes using m-phenylenediamine and trimesoyl chloride. Within two molecular layers, desalination performance was affected. As film thickness increased to 15 nm (48 MLD cycles), performance progressed from nanofiltration to reverse osmosis metrics in terms of salt rejection and water permeance. With film thickness > 5 nm, rejection values exceeded a small sampling of commercial membranes. In all cases, a tradeoff between rejection and permeance was observed. Atomic force microscopy measurements indicate that MLD enhancement led to removal of small-scale roughness features and resulted in a root mean square roughness difference of <0.1 nm from the substrate. These initial MLD studies represent a novel processing approach that offers a potential pathway for the fabrication of membranes with finely tailored properties.

最近半导体器件向近原子尺度的发展需要开发原子层处理方法，包括分子层沉积 (MLD)。这种气相沉积技术可以精确控制成分和厚度，形成半透性聚合物薄膜。在这里，MLD 被用来生产薄膜复合反渗透膜。使用m将薄至 0.5 nm 的芳族聚酰胺薄膜应用于 NF270 纳滤膜-苯二胺和均苯三甲酰氯。在两个分子层内，脱盐性能受到影响。随着薄膜厚度增加到 15 nm（48 个 MLD 循环），性能从纳滤发展到反渗透指标，如脱盐率和水渗透率。膜厚 > 5 nm 时，截留值超过了少量商用膜样本。在所有情况下，都观察到拒绝和渗透之间的权衡。原子力显微镜测量表明，MLD 增强导致去除小尺度粗糙度特征，并导致与基板的均方根粗糙度差异 <0.1 nm。这些最初的 MLD 研究代表了一种新的加工方法，为制造具有精细定制特性的膜提供了潜在的途径。