磷酸电解液中铝阳极氧化过程中孔隙成核与重排动力学的控制

doi:10.61558/2993-074X.3600

摘要/Abstract

摘要：

孔间距为几百纳米的阳极氧化铝多孔膜因其与可见光和近红外光的独特相互作用以及高达1500 °C的高热稳定性而备受关注。这些多孔膜是在弱酸中以高电压对铝进行阳极氧化制备的，这导致多孔结构形成的初始阶段动力学较慢。在此，我们提出了一种在基于弱酸（如磷酸）的电解质中加速阳极氧化铝形成的方法。使用铝箔作为基材，铝箔在不同条件下通过第一次阳极氧化预先形成图案，然后选择性溶解牺牲阳极氧化铝层。铝表面的形貌，包括表面粗糙度和金字塔尖峰的高度，在第二次阳极氧化过程中的孔成核和重排过程中起着至关重要的作用。具体而言，通过在低电压（如25 V）下强酸电解液（如0.3 mol·L^-1硫酸）中进行首次阳极氧化，可以使在磷酸中进行第二次阳极氧化时孔隙成核和随后达到稳态的速度加倍。因此，如果在第一次阳极氧化过程中使用强酸电解液对铝表面进行预图案化，则在磷酸中的两步阳极氧化过程中可以节省约2小时。

关键词: 阳极氧化铝, 动力学, 两步阳极氧化, 磷酸, 电化学预图案化

Abstract:

:Anodic aluminium oxide (AAO) porous films with an interpore distance of several hundred nanometers are of great interest due to their unique interaction with visible and near-infrared light, and high thermal stability up to 1500 °C. These porous films are prepared by aluminium anodizing at high voltages in weak acids, leading to a slow kinetics of initial stages of porous structure formation. Here, we propose an approach to accelerate AAO formation in electrolytes based on weak acids such as phosphoric acid. Aluminium foils, pre-patterned using first anodizing under different conditions and subsequent selective dissolution of a sacrificial AAO layer, were utilized as substrates. The morphology of the aluminium surface, including surface roughness and height of pyramidal spikes, plays a crucial role in the pore nucleation and rearrangement process during the second anodizing. In particular, by first anodizing in strong acid electrolytes at low voltages (such as 0.3 M sulfuric acid at 25 V), it is possible to double the rate of pore nucleation and subsequent reach of the steady-state regime during second anodizing in phosphoric acid. As a result, about 2 hours can be saved during the two-step anodizing process in phosphoric acid if a strong acid electrolyte is used for the first anodizing to pre-pattern aluminium surface.

Key words: Anodic aluminium oxide, Kinetics, Two-step anodizing, Phosphoric acid, Electrochemical pre-patterning

Ilya V. Roslyakov, Nikita A. Shirin, Dmitry M. Tsymbarenko, Sergei N. Pavlov, Sergey E. Kushnir, Nikolay V. Lyskov, Kirill S. Napolskii. 磷酸电解液中铝阳极氧化过程中孔隙成核与重排动力学的控制[J]. 电化学（中英文）, 2026, 32(2): 2507091.

Ilya V. Roslyakov, Nikita A. Shirin, Dmitry M. Tsymbarenko, Sergei N. Pavlov, Sergey E. Kushnir, Nikolay V. Lyskov, Kirill S. Napolskii. Control of Pore Nucleation and Rearrangement Kinetics During Aluminium Anodizing in Phosphoric Acid Electrolyte[J]. Journal of Electrochemistry, 2026, 32(2): 2507091.

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链接本文: https://electrochem.xmu.edu.cn/CN/10.61558/2993-074X.3600

https://electrochem.xmu.edu.cn/CN/Y2026/V32/I2/2507091

图/表 10

参考文献 62

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ID	Electrolyte composition	Temperature (T, °C)	Anodizing voltage (U, V)	Charge density (q, C·cm⁻²)
AAS25	0.3 mol·L^-1 H₂SO₄	3 ± 1	25	20
AAO40	0.3 mol·L^-1 H₂C₂O₄	3 ± 1	40	20
AASe48	0.3 mol·L^-1 H₂SeO₄	1.0 ± 0.1	48 (sweep 0.5 V·s⁻¹)	100
AAP195	0.1 mol·L^-1 H₃PO₄	0.1 ± 0.1	195 (sweep 0.5 V·s⁻¹)	18

ID	Interpore distance (SEM), nm	Fraction of pores in hexagonal coordination (SEM), %	Interpore distance (AFM), nm	Surface roughness (S_a), nm	Spike height (H_s), nm
Electropolished Al	41.2 ± 0.7	39 ± 6	−	2.67 ± 0.12	−
AAS25	64.9 ± 0.2	79.0 ± 0.1	64.0 ± 0.7	3.13 ± 0.11	5.6 ± 0.9
AAO40	104.7 ± 0.3	66.0 ± 1.0	103.6 ± 0.2	4.98 ± 0.03	8.8 ± 1.3
AASe48	113.4 ± 0.3	62.0 ± 0.1	113.2 ± 0.1	10.21 ± 0.23	14.9 ± 1.6
AAP195	492.9 ± 0.1	56.5 ± 0.4	483.7 ± 1.4	69.01 ± 0.28	179 ± 15

Parameter	Electropolished Al	AAS25	AAO40	AASe48	AAP195
R, nm	249	321	405	346	507
r, nm	69	141	225	166	327
j, mA·cm⁻²	0.22 ± 0.04	0.31 ± 0.10	0.20 ± 0.02	0.30 ± 0.12	0.59 ± 0.06
v_f × 10⁻¹⁴, cm⁻²·s⁻¹	0.75	1.61	1.11	1.57	2.01