自组装法制备中空二氧化硅纳米粒子减反射薄膜

doi:10.15541/jim20130632

摘要/Abstract

摘要：

以正硅酸乙酯(TEOS)为壳层材料, 聚丙烯酸(PAA)为核材料, 以传统的Stöber水解法为基础制备得到结构规整的中空二氧化硅纳米粒子, 并采用自组装法制备单层减反射薄膜和宽波段双层减反射薄膜。主要研究中空二氧化硅纳米粒子的结构调控方法; 自组装次数和中空二氧化硅纳米粒子分散液的pH值对减反射薄膜透光率的影响规律, 以及具有渐变折射率的双层减反射薄膜的制备。研究结果表明: 通过调节PAA和TEOS的用量可精确调控中空二氧化硅纳米粒子的粒径和空腔体积分率, 进而可精确调控减反射薄膜的厚度和折射率; 通过酸洗工艺, 将自组装次数由10次减少为2次, 简化了涂膜的工艺条件, 在最佳工艺条件下所制备的单层减反射薄膜在350~800 nm波长范围内可显著提高玻璃的透光率, 在最佳波长(λ=520 nm)处将玻璃的透光率由91.6%提高至98.1%; 双层减反射薄膜可在更宽的波段范围内提高基材的透光率, 在400~1500 nm波长范围内将玻璃的透光率提高了5%以上。

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关键词: 中空二氧化硅纳米粒子, 减反射薄膜, 透光率, 自组装法

Abstract:

Using tetraethyl orthosilicate (TEOS) as raw material and polyacrylic acid (PAA) as nucleating material, hollow silica nanoparticles were synthesized on the basis of traditional method of Stöber. Using hollow silica nanoparticles, both single-layer anti-reflection coatings and broad-band double-layer anti-reflection coatings were prepared by self-assembly. The structure control of the hollow silica nanoparticles, the effect of deposition cycle, pH value of the hollow silica nanoparticle dispersion on transmittance of coatings, and the preparation of the double-layer anti-reflection coatings with a graded-refractive-index were investigated. The results show that the size and void fraction of the hollow silica nanoparticles can be controlled precisely by changing the amount of PAA and TEOS. The thickness and refractive index of the anti-reflection coatings can also be tuned accurately in the same way. The deposition cycles are reduced from 10 cycles to 2 cycles by acid pickling which simplifies the coating process. This new technique significantly increases the transmittance of glass substrate coated by single-layer anti-reflection coatings in the range of 350-800 nm under optimum conditions, and improves the maximum transmittance from 91.6% to 98.1% at optimized wavelength (λ=520 nm). Furthermore, glass substrate coated by double-layer anti-reflection coatings can increase the transmittance more than 5% in a much wider wavelength range (400-1500 nm).

Key words: hollow silica nanoparticle, anti-reflection coating, transmittance, self-assembly

中图分类号:

TQ127

孙志娟, 陈雪莲, 蒋春跃. 自组装法制备中空二氧化硅纳米粒子减反射薄膜[J]. 无机材料学报, 2014, 29(9): 947-955.

SUN Zhi-Juan, CHEN Xue-Lian, JIANG Chun-Yue. Preparation of Anti-reflection Coatings with Hollow Silica Nanoparticles by Self-assembly[J]. Journal of Inorganic Materials, 2014, 29(9): 947-955.

图/表 11

表1 制备中空二氧化硅纳米粒子的实验设计

Table 1 Experimental design of the preparation of hollow silica nanoparticles

Run	Amount of ammonia/mL	Amount of PAA /g	Amount of TEOS /mL
1	4.50	0.75	3.50
2	6.75	0.75	3.50
3	9.00	0.75	3.50
4	6.75	0.60	1.30
5	6.75	0.80	1.75
6	6.75	1.00	2.20
7	6.75	0.90	6.00
8	6.75	0.90	5.00
9	6.75	0.90	4.00
10	6.75	0.90	3.00
11	6.75	0.90	2.00

图1 不同氨水用量时中空二氧化硅纳米粒子的TEM照片

Fig. 1 TEM images of hollow silica nanoparticles with ammonia amount of 4.50 mL (a), 6.75 mL (b) and 9.00 mL (c)

图2 不同PAA用量时中空二氧化硅纳米粒子的TEM照片和粒径分布图

Fig. 2 TEM images and particle size distributions of hollow silica nanoparticles with various amount of PAA (a, b) PAA/TEOS=0.60 g/1.30 mL; (c, d) PAA/TEOS=0.80 g/1.75 mL; (e, f) PAA/TEOS=1.00 g/2.20 mL

图3 不同TEOS用量制备的中空二氧化硅纳米粒子的TEM照片及TEOS用量与空腔体积分率关系图

Fig. 3 TEM images of hollow silica nanoparticles with TEOS amount of 6.00 mL(a), 5.00 mL(b), 4.00 mL(c), 3.00 mL(d) and 2.00 mL(e), and the curve of relation between the amount of TEOS and the void fraction (f)

图4 酸洗对自组装次数的影响

Fig. 4 Effect of acid pickling on deposition cycles

图5 非酸洗(a, b)和酸洗(c, d)工艺所制备的单层减反射薄膜的SEM照片

Fig. 5 SEM images of the single-layer anti-reflection coatings by no acid pickling (a, b) and acid pickling(c, d)

图6 自组装次数对薄膜透光率的影响

Fig. 6 Effect of deposition cycle on the transmittance of the coatings

图7 不同自组装次数所制备的单层减反射薄膜的SEM照片

Fig. 7 SEM images of the single-layer anti-reflection coatings with various deposition cycles (a, b) Coating 1 time; (c, d) Coating 2 times; (e, f) Coating 3 times

图8 中空二氧化硅纳米粒子分散液的pH值对薄膜透光率的影响

Fig. 8 Effect of pH value of the hollow silica nanoparticle dispersion on the transmittance of the coatings

表2 制备的单层防减反射薄膜的具体性能参数

Table 2 The specific property parameters of single-layer anti-reflection coatings

Sample	Hollow silica nanoparticles dispersion pH	Thickness of the coatings / nm	Refractive index of the coatings	Optimized wavelength / nm	Maximum transmittance / %
1	1.5	72	1.18	475	95.3
2	2.5	101	1.23	520	98.1
3	3.0	96	1.22	510	97.4
4	3.5	91	1.21	505	96.8
5	4.5	79	1.20	495	96.2

图9 宽波段双层减反射薄膜与单层减反射薄膜的透光率

Fig. 9 Transmittance of both double-and single-anti-reflection coatings (a) Transmittance; (b) Increased amount of transmittance

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