Graphene and MoS 2 were dispersed in Esterified Bio-Oil (EBO) and evaluated as lubricants for steel/steel contact. The tribological behaviors of steel/steel pairs were investigated under lubrication of graphene/MoS 2 blends with different mass ratios, loads and rotating speeds.The micro-morphologies of the worn surfaces were observed by optical and Scanning Electron Microscopy (SEM). The components of the additives and chemical valences of the elements on the rubbed surfaces were analyzed using Raman and X-ray Photoelectron Spectroscopy (XPS). A synergistic lubricating effect for both graphene and MoS 2 with contents of 0.5 wt.% as additives dispersed in EBO was observed that reduced the friction coefficient and wear of the steel specimens under boundary lubrication regime conditions. This was ascribed to the formation of a thicker adsorbed tribo film containing graphene, MoS 2 and organics from the EBO. Graphene was shown to improve the retention of MoS 2 on the frictional surfaces and prevent oxidation during rubbing.MoS 2 , on the other hand, prevented the graphene from being ground into small and defective platelets. Corresponding author. Tel/

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High‐performance droplet transport is crucial for diverse applications including biomedical detection, chemical micro‐reaction, and droplet microfluidics. Despite extensive progress, traditional passive and active strategies are restricted to limited liquid types, small droplet volume ranges, and poor biocompatibilities. Moreover, more challenges occur for biological fluids due to large viscosity and low surface tension. Here, a vibration‐actuated omni‐droplets rectifier (VAODR) consisting of slippery ratchet arrays fabricated by femtosecond laser and vibration platforms is reported. Through the relative competition between the asymmetric adhesive resistance originating from the lubricant meniscus on the VAODR and the periodic inertial driving force originating from isotropic vibration, the fast (up to ≈60 mm s−1), programmable, and robust transport of droplets is achieved for a large volume range (0.05–2000 µL, Vmax/Vmin ≈ 40 000) and in various transport modes including transport of liquid slugs in tubes, programmable and sequential transport, and bidirectional transport. This VAODR is general to a high diversity of biological and medical fluids, and thus can be used for biomedical detection including ABO blood‐group tests and anticancer drugs screening. These strategies provide a complementary and promising platform for maneuvering omni‐droplets that are fundamental to biomedical applications and other high‐throughput omni‐droplet operation fields.

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