En-Hou Han

Owing to its inherent electrical conductivity, reversible redox activity, and structural versatility, polypyrrole (PPy) has become an important material for advanced functional coatings. This review summarizes recent advances in PPy-based coatings, systematically exploring the correlation between fundamental material design and macroscopic multifunctional applications. First, the core structural characteristics of PPy and its primary fabrication strategies, including electrochemical deposition, chemical oxidative polymerization, solution processing, and hybrid composite engineering, are delineated. Subsequently, the role of PPy in surface protection is analyzed, with an emphasis on the synergistic mechanisms underlying corrosion mitigation, mechanical durability, and environmental barriers (e.g., anti-fouling and solar-driven desalination). In addition, the application expansion of PPy in emerging fields, such as electromagnetic interference (EMI) shielding, highly sensitive smart sensing, electroactive energy interfaces, and advanced biomedical electrodes, is summarized. Finally, current challenges—particularly the physicochemical trade-offs among conductivity, interfacial adhesion, and long-term stability—are discussed, and future development directions are prospected. By integrating green processing technologies and data-driven smart system integration, next-generation PPy coatings are expected to meet the demands of flexible electronics, sustainable energy, and precision medicine.

Nuclear power components contain radioactivity on their surfaces after long-term service, which can be harmful to personnel and the environment during maintenance, dismantling, and decommissioning. In this experiment, laser decontamination technology is utilized to remove radioactivity from their surfaces. In order to meet the actual needs, a laser decontamination process without spot overlapping has been studied. Under the same equipment conditions, the decontamination efficiency of the non-spot overlapping process is 10 times higher than that of the spot overlapping process. Alloy 690 is used as the test substrate, and non-radioactive specimens are prepared by simulating primary-circuit hydrochemical conditions. The surface morphology, elemental composition, and phase composition of the specimens before and after laser decontamination are investigated with SEM and XRD using the single-pulse experiment and power single-factor experiment methods, and the laser decontamination effect was evaluated. The results show that the decontamination efficiency reached 10.8 m²/h under the conditions of a pulse width of 500 ns, a laser repetition frequency of 40 kHz, a scanning speed of 15,000 mm/s, and a line spacing of 0.2 mm, according to which the removal effect was achieved when the laser power was 160 W and the oxygen content on the surface was 6.29%; additionally, there were no oxide phases in the XRD spectra after decontamination. Therefore, the laser cleaning process without spot overlap can provide reference for future practical operations to achieve efficient removal of radioactivity from nuclear power components.