An Ning, Chen Tiantian, Zhang Junfeng, Wang Guanghui, Yan Mi, Yang Shikuan
Institute for Composites Science Innovation, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
School of Physics and Information, Shanxi Normal University, Taiyuan, 030031, China.
Small Methods. 2024 May;8(5):e2300910. doi: 10.1002/smtd.202300910. Epub 2024 Feb 28.
Rational morphology control of inorganic microarchitectures is important in diverse fields, requiring precise regulation of nucleation and growth processes. While wet chemical methods have achieved success regarding the shape-controlled synthesis of micro/nanostructures, accurately controlling the growth behavior in real time remains challenging. Comparatively, the electrodeposition technique can immediately control the growth behavior by tuning the overpotential, whereas it is rarely used to design complex microarchitectures. Here, the electrochemical design of complex CuO microarchitectures step-by-step by precisely controlling the growth behavior is demonstrated. The growth modes can be switched between the thermodynamic and kinetic modes by varying the overpotential. Cl ions preferably adhered to {100} facets to modulate growth rates of these facets is proved. The discovered growth modes to prepare CuO microarchitectures composed of multiple building units inaccessible with existing methods are employed. Polyvinyl alcohol (PVA) additives can guarantee all pre-electrodeposits simultaneously evolve into uniform microarchitectures, instead of forming undesired microstructures on bare electrode surfaces in following electrodeposition processes is discovered. The designed CuO microarchitectures can be converted into noble metal microstructures with shapes unchanged, which can be used as surface-enhanced Raman scattering substrates. An electrochemical avenue toward rational design of complex inorganic microarchitectures is opened up.
无机微结构的合理形态控制在多个领域都很重要，这需要对成核和生长过程进行精确调控。虽然湿化学方法在微/纳米结构的形状控制合成方面取得了成功，但实时精确控制生长行为仍然具有挑战性。相比之下，电沉积技术可以通过调节过电位立即控制生长行为，然而它很少用于设计复杂的微结构。在此，展示了通过精确控制生长行为逐步对复杂CuO微结构进行电化学设计。通过改变过电位，可以在热力学模式和动力学模式之间切换生长模式。证明了Cl离子优先附着在{100}晶面上以调节这些晶面的生长速率。采用所发现的生长模式来制备由现有方法无法获得的多个构建单元组成的CuO微结构。发现聚乙烯醇（PVA）添加剂可以保证所有预电沉积物同时演变成均匀的微结构，而不是在后续电沉积过程中在裸电极表面形成不期望的微结构。所设计的CuO微结构可以转化为形状不变的贵金属微结构，可用作表面增强拉曼散射基底。开辟了一条通向复杂无机微结构合理设计的电化学途径。
