Developing ecofriendly anticorrosion coating has great demand for marine protection. Incorporation of nontoxic inorganic fillers into waterborne epoxy (WEP) coating shows tremendous potential for enhancing corrosion resistance. However, the application of MXene/WEP coating is limited by the poor dispersion of MXene in WEP and insufficient corrosion resistance. Herein, a polydopamine (PDA) modified MXene-CeO 2 @PDA (MCP) filler is constructed by a combination of CeO 2 with MXene and embedded into WEP to form ecofriendly anticorrosion MCP/WEP coating. Dispersion of MXene in WEP is improved by the introduction of CeO 2 and PDA modification. Benefiting from the synergy of the physical labyrinth effect of MXene and the chemical inhibition effect of CeO 2 , MCP/WEP coating exhibits remarkable anticorrosion behavior in 3.5 wt% NaCl solution with a low corrosion rate (CR) of 4.48 × 10 −6 mpy, which is three orders of magnitude lower than that of blank WEP (4.78 × 10 −3 mpy). Moreover, MCP/WEP presents long-term and stable corrosion protection for over 30 days. The results reveal the incorporation of MCP significantly promotes the anticorrosion performance of WEP.
In recent years, multifunctional sensors have attracted significant attention due to their ability to detect different types of signals. However, it still remains a challenge to develop flexible materials with multiple sensing functions. Herein, we propose a strategy to fabricate multifunctional flexible textiles (PCP) that can apply piezoelectric and piezo-phototronic effects to self-powered piezoelectric sensor and photodetector (PD) by utilizing the synergistic effect of polydopamine-coated cerium oxide (CeO 2 @PDA) nanoparticles and poly (vinylidene fluoride) (PVDF). The CeO 2 @PDA nanoparticles served as local nucleating agents and photosensitizers for the PVDF, enhancing the polar crystalline phase and inducing piezoelectric effect, semiconductor, and optical process coupling in PCP textiles. The piezoelectric sensors consisting of PCP textiles produced extremely high sensitivity (1–10 kPa: 1.27 V/kPa; 10–50 kPa: 0.085 V/kPa; 50–100 kPa: 0.02 V/kPa) and significant electrical output (25.5 V and 0.37 μA). Besides, the piezoelectric sensor had extensive applications including pulse wave measurement, limb motion detection, and active voice recognition. It's especially noteworthy that the PD based on PCP textiles is sensitive for the detecting of sunlight illumination as confirmed by response time (t On = 2 s and t Off = 4.6 s). Meanwhile, the fabricated self-powered PD showed significant improvement in output current, confirming the realization of the piezo-phototronic effect in PCP textiles. In this work, the low-cost and high-efficiency multifunctional sensing materials were successfully prepared, providing a novel approach for the next generation of self-powered piezoelectric sensors and photodetectors.
Jie Yang,Wenhui Yao,Daizhi Chen,Xin Li,Jiaming Yan,Liang Wu,Young-Rae Cho,Xianhua Chen
A novel nanofiller-reinforced SLIPS is developed on AZ31 Mg alloys. • CeO 2 @PDA/h-BN nanofillers enhance the corrosion resistance and self-healing properties of coatings. • Self-healing ability is due to rapid lubricant redistribution and passive film formation. • The coating shows better long-term corrosion protection than conventional SLIPSs. Conventional slippery liquid-infused porous surfaces (SLIPSs) have emerged as an effective strategy to protect Mg alloys from corrosion. However, their anti-corrosion and self-healing performances remain insufficient for long-term service. Therefore, multifunctional CeO 2 @PDA/h-BN nanofillers were incorporated into liquid lubricant to fabricate nanofiller-reinforced SLIPSs (CeO 2 @PDA/h-BN-SLIPSs). In particular, this study systematically investigated influences of nanofiller concentrations on surface morphology, hydrophobicity, and electrochemical behavior. CeO 2 @PDA/h-BN-SLIPS-8, prepared at a concentration of 8 mg/mL, displayed the lowest corrosion current density (8.22 × 10 -11 A/cm 2 ) and the highest impedance modulus (9.06 × 10 8 Ω cm 2 at 0.01 Hz). This was ascribed to the synergistic effects of high surface hydrophobicity provided by a lubricant layer, tortuous diffusion pathways provided by h-BN nanosheets, ion-exchange property of MgAl-LDH, and active corrosion inhibition of CeO 2 . In addition, scanning vibration electrode technique (SVET) analysis confirmed good self-healing behavior of CeO 2 @PDA/h-BN-SLIPS-8, arising from both rapid lubricant redistribution and formation of protective cerium-based passive films. Overall, this study provides an effective strategy for fabrication of robust anti-corrosive and self-healing SLIPSs, offering enhanced corrosion protection for Mg alloys in industry.