Advanced Solid Lubrication with COK‐47: Mechanistic Insights on the Role of Water and Performance Evaluation

• DOI: 10.1002/advs.202415268
• Publication Date: 2025-01-14T07:47:16Z
• Authors: Hanglin Li; Xudong Sui; Pablo Ayala; Edoardo Marquis; Hannah Rabl; Adrian Ertl; Pierluigi Bilotto; Yazhuo Shang; Jiusheng Li; Lu Xu; Maria Clelia Righi; Dominik Eder; Carsten Gachot

Metal-organic framework (MOF) nanoparticles have attracted widespread attention as lubrication additives due to their tunable structures and surface effects. However, solid properties been rarely explored. This work introduces the positive role of moisture in case a newly described Ti-based MOF (COK-47) powder. COK-47 achieves an 8.5-fold friction reduction compared AISI 304 steel-on-steel sliding under room air. In addition, maintains similarly low coefficient (0.1-0.2) on various counterbodies, including Al2O3, ZrO2, SiC, Si3N4. Notably, other widely studied MOFs (ZIF-8, ZIF-67) 2D materials powder (MXene, TMD, rGO), exhibits lowest (≈0.1) same experimental settings. Raman spectroscopy, X-ray diffraction, photoelectron energy dispersive scanning electron microscope, transmission microscopy indicate that tribofilm is amorphous film obtained by hydrolysis air with moisture. Density functional theory further confirms water catalyzes decomposition COK-47, crucial step forming tribofilm. study demonstrates idea utilizing water-assisted mechanisms. It provides new insights into applications tribology highlights interdisciplinary contributions mechanical engineering chemistry.