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Octyl hydroxamic acid (OHA) was investigated as an inhibitor in H2O2-based alkaline silica dispersions for the polishing of cobalt (Co) films for interconnect applications. A combination of experiments and density functional theory (DFT) was used to investigate the inhibition effect and the mechanism of OHA on the Co surface. On the basis of the experiments, it can be proven that OHA has an inhibition effect on Co, which came from the inhibition of the cathodic reaction. The X-ray photoelectron spectroscopy (XPS) experiments show that the adsorption of OHA weakened the oxidation of the Co surface and protected the Co surface from corrosion. On the basis of the calculations, it can be proven that the OHAketone (ion) is most likely to react with the Co surface, and it can adsorb on the Co surface by Co–O bonds. This study provides important microscopic insights for understanding the corrosion protection of Co interconnect metals and helps to explain the corrosion inhibition mechanism of the organic–metal interface during the CMP process.

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Sensors used in the Internet of Things (IoT) should be cost‐effective and easy to maintain. Triboelectric sensors made of polymers have good development prospects. Herein, a self‐powered multifunctional motion sensor (MMS) is proposed to sense the speed, acceleration, and direction of linear and rotational motions, and detect the frequency of vibration. The MMS comprises a polyurethane (PU) ball encapsulated in a 3D‐printed cylindrical shell, the inner walls of which are lined with Cu electrodes coated with a polytetrafluoroethylene (PTFE) film. The scanning electron microscopy results show that the surface area of the PU ball can be effectively increased through wet etching with sulfuric acid. The charge transfer law is analyzed and simulated using the finite element method. The finite element simulation and experimental results prove that the MMS exhibits a good sensing performance. The MMS is successfully applied to the motion detection of a self‐balancing scooter and human activity state. It can also detect small vibrations and rotational speed. The proposed MMS has broad application prospects in the field of IoT.