Persistent incommensurate amorphous/crystalline meta-interfaces enable engineering-grade superlubricity

TL;DR

This paper demonstrates that amorphous/crystalline heterointerfaces can achieve robust superlubricity under real-world conditions, offering a new materials-agnostic strategy to reduce friction in engineering applications.

Contribution

Introducing a general design paradigm using amorphous/crystalline interfaces for engineering-grade superlubricity, validated through experiments and simulations with hierarchical interface structures.

Findings

Achieved ultra-low friction coefficient (~0.008) over 100,000 cycles.

Demonstrated incommensurability persists under extreme conditions.

Hierarchical interfaces enhance load distribution and durability.

Abstract

Friction dissipates a substantial portion of global energy, motivating the pursuit of superlubricity, a state of near-zero friction, in real-world systems. Conventional approaches rely on crystalline lattice mismatch to suppress periodic energy barriers, but real interfaces invariably contain defects, edges and grain boundaries that restore high-friction states. Here we introduce a materials-agnostic strategy based on amorphous/crystalline heterointerfaces to achieve robust superlubricity under engineering-relevant conditions. Using diamond-like carbon (DLC) and crystalline MoS2 as a model system, we show through experiments and atomistic simulations that their interface remains incommensurate at all orientations and exhibits vanishing energy barriers during friction. In contrast, twisted MoS2 bilayers readily reorient into commensurate, high-friction states. We scale this effect by fabricating laser-patterned arrays of DLC/MoS2 meta-contacts reinforced with Ti3C2Tx MXene, forming hierarchical interfaces that sustain a friction coefficient of ~0.008 over 100000 cycles under combined extreme conditions: millimetre-scale contact size, 12.7 GPa contact pressure and RH 40% air. This unprecedented performance arises from four synergistic factors: intrinsic incommensurability at amorphous/crystalline interface, the rigidity of DLC support, MXene-based mechanical reinforcement and normalized load distribution by geometric patterning. These findings establish a general design paradigm that extends structural superlubricity from nanoscale model systems to practical technologies for sustainable engineering.