Abstract The most engineering application for the molecular self-assembly of sulfydryl compounds on solid surfaces is froth flotation. In this work, the hydrophobic mechanism of 3-hexyl-4-amino-1,2,4-triazole-5-thione (HATT) on chalcopyrite (CuFeS2) was first investigated by in situ atomic force microscopy (AFM), in situ scanning electrochemical microscopy (SECM), time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS), contact angle and flotation tests. In situ AFM imaging elucidated that HATT might aggregate on chalcopyrite surface to form self-assembled monolayers. In situ SECM images confirmed the weakened tip current of chalcopyrite region after HATT adsorption. On the self-assembly layers, HATT bound overwhelmingly with copper atoms to form a five-membered-ring Cu(I)-HATT surface complex, accompanying with the reduction of cupric to cuprous. HATT anchored on chalcopyrite surfaces through its exocyclic S and N atoms of 4-amino-1,2,4-triazole-5-thione group and left its hexyl group towards aqueous solutions, resulting in an enhanced surface hydrophobicity to improve the flotation recovery of copper minerals. This fundamental understanding inspired by in situ approaches will promote the innovation and development of novel flotation surfactants.

中文翻译：

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原位探测 3-hexyl-4-amino-1,2,4-triazole-5-thione 在黄铜矿表面的自组装

摘要 在固体表面进行巯基化合物分子自组装的工程应用最多的是泡沫浮选。在这项工作中，3-己基-4-氨基-1,2,4-三唑-5-硫酮（HATT）对黄铜矿（CuFeS2）的疏水机制首次通过原位原子力显微镜（AFM）进行了研究，原位扫描电化学显微镜 (SECM)、飞行时间二次离子质谱 (ToF-SIMS)、X 射线光电子能谱 (XPS)、接触角和浮选测试。原位 AFM 成像阐明 HATT 可能在黄铜矿表面聚集形成自组装单层。原位 SECM 图像证实了 HATT 吸附后黄铜矿区域的尖端电流减弱。在自组装层上，HATT 压倒性地与铜原子结合形成五元环 Cu(I)-HATT 表面复合物，伴随着铜还原为亚铜。HATT 通过其 4-氨基-1,2,4-三唑-5-硫酮基团的外环 S 和 N 原子锚定在黄铜矿表面，并将其己基留在水溶液中，从而增强了表面疏水性，以提高浮选回收率铜矿。这种受原位方法启发的基本理解将促进新型浮选表面活性剂的创新和发展。