基体温度对悬浮液等离子喷涂TiO2涂层性能的影响

Effect of Substrate Temperature on Properties of TiO2 Coatings Sprayed by Plasma Suspension

摘要:

采用悬浮液等离子喷涂技术（SPS），在不同基体温度下成功地制备了TiO₂涂层。通过研究基体温度对TiO₂涂层光催化性能及机械性能的影响，探究适合TiO₂光催化涂层的最佳基体温度。通过场发射扫描电子显微镜、X射线衍射仪、同步热分析仪、紫外-可见光谱仪等，对TiO₂涂层微观形貌、物相组成、光吸收性能进行了详细分析；通过光催化测试、结合强度测试和划痕测试，深入研究了基体温度对涂层光催化性能及机械性能的影响。研究结果表明：随着基体温度由250 ℃降到110 ℃，涂层的锐钛矿含量逐渐增加了15%，间接带间隙减小了0.5 eV，同时可见光吸收强度显著提高；在可见光照射下，亚甲基蓝去除率增加了11%；随着基体温度的降低，涂层的机械性能有所减弱，结合强度降低了12.28 MPa，划痕试验的正常临界载荷减小1.77 N。该研究为选择TiO₂光催化涂层最佳基体温度提供了重要依据。

Abstract:

TiO₂ coatings were fabricated using suspension plasma spraying （SPS） technology at varying substrate temperatures. This study investigates the impact of substrate temperature on both the photocatalytic and mechanical properties of TiO₂ coatings， aiming to identify the optimal substrate temperature for TiO₂ photocatalytic coatings. The microstructure， phase composition and optical properties of TiO₂ coatings were thoroughly analyzed through techniques such as field emission scanning electron microscopy， X-ray diffractometry， synchronous thermal analysis and UV-VIS spectrometry. Additionally， the structural morphology and optical characteristics of the deposited coatings were examined. Photocatalytic experiments， bonding strength tests and scratch tests were conducted to comprehensively explore the influence of substrate temperature on the photocatalytic and mechanical properties of the coating. As the substrate temperature decreases from 250 ℃ to 110 ℃， the anatase content in the coating gradually increases by 15%， resulting in a reduction of the indirect band gap by 0.5 eV. This change enhances the absorption intensity of visible light， leading to an 11% increase in the methylene blue removal rate under visible light. However， the reduction in substrate temperature is accompanied by a decrease in mechanical properties， including a 12.28 MPa reduction in the binding strength ， and a 1.77 N reduction in the normal critical load of scratch test . These findings provide essential insights for determining the optimum substrate temperature for TiO₂ photocatalytic coatings.