Electrophoretic Deposition of Hybrid Calcium Alginate-Gold Nanoparticle Hydrogel Films via Catalyzed Electrooxidation of Hydroquinone
Electrophoretic Deposition of Hybrid Calcium Alginate-Gold Nanoparticle Hydrogel Films via Catalyzed Electrooxidation of Hydroquinone
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通过对苯二酚催化电氧化电泳沉积杂化海藻酸钙-金纳米粒子水凝胶膜
DOI：
10.1021/acs.langmuir.3c00429
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发表时间：
2023
期刊：
影响因子：
3.9
通讯作者：
Zamborini, Francis P.
中科院分区：
文献类型：
--
作者：
Nambiar, Harikrishnan N.;Zamborini, Francis P.
杂化海藻酸盐 (Alg)-Au 纳米粒子 (NP) 薄膜的电泳沉积 (EPD) 是由于直径为 4 和 15 nm 的柠檬酸盐包覆的金纳米颗粒 (cit-Au NP) 催化的氢醌 (HQ) 氧化导致电极表面局部 pH 值下降的结果。电极处的局部 pH 下降导致 Alg 和 cit 中和，从而同时导致 Alg 和 cit-Au NP 的 EPD。用 Ca2+ 溶液对薄膜进行后处理，形成混合 Ca-Alg-Au NP 水凝胶薄膜。在 4 nm cit-Au NP 存在的情况下，Alg 的 EPD 发生在~0.8 V（相对于 Ag/AgCl），而在 15 nm cit-Au NP 存在的情况下，Alg 的 EPD 为~1.0 V，在不存在 cit-Au NP 的情况下，Alg 的 EPD 为~1.4 V。这是由于与 15 nm cit-Au NP 相比，4 nm cit-Au NP 对 HQ 的氧化具有更高的催化活性。 Ca-Alg-Au NP 水凝胶薄膜的紫外可见光谱显示了水凝胶中捕获的 Ca-Alg 和 Au NP 的吸收特征。随着EPD溶液中Au NPs浓度的增加，Au NPs的Ca-Alg吸光度和局域表面等离子体共振（LSPR）峰增加，证实了Au NPs作为Alg EPD催化剂的作用。 Ca-Alg-Au NP 水凝胶薄膜的衰减全反射傅里叶变换红外 (ATR-FTIR) 光谱显示了 Ca-Alg 和质子化海藻酸基团的特征峰。在恒定 EPD 电势和时间下，与不含 cit-Au NP 的水凝胶相比，含有 cit-Au NP 的水凝胶厚度更大。在低电位下形成Ca-Alg和杂化Ca-Alg-Au NP水凝胶薄膜在电化学和光学传感器开发、催化和生物研究中具有潜在应用。
The electrophoretic deposition (EPD) of hybrid alginate (Alg)-Au nanoparticle (NP) films results from the localized pH drop at the electrode surface due to oxidation of hydroquinone (HQ) catalyzed by 4 and 15 nm diameter citrate-coated gold NPs (cit-Au NPs). The localized pH drop at the electrode leads to neutralization of both Alg and cit, leading to EPD of both Alg and cit-Au NPs simultaneously. Post-treatment of the film with Ca2+solution leads to hybrid Ca-Alg-Au NP hydrogel films. The EPD of Alg in the presence of 4 nm cit-Au NPs occurs at ∼0.8 V (vs Ag/AgCl) as compared to ∼1.0 V in the presence of 15 nm cit-Au NPs and ∼1.4 V in the absence of cit-Au NPs. This is due to the higher catalytic activity of 4 nm cit-Au NPs compared to 15 nm cit-Au NPs for the oxidation of HQ. UV–vis spectra of Ca-Alg-Au NP hydrogel films show absorbance features for both Ca-Alg and Au NPs entrapped within the hydrogel. As the concentration of Au NPs in the EPD solution increases, the Ca-Alg absorbance and localized surface plasmon resonance (LSPR) peak of the Au NPs increases, confirming the role of the Au NPs as a catalyst for EPD of Alg. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra of the Ca-Alg-Au NP hydrogel films show characteristic peaks for Ca-Alg and protonated alginic acid groups. The hydrogel thickness is greater with cit-Au NPs compared to without cit-Au NPs at constant EPD potential and time. Forming Ca-Alg and hybrid Ca-Alg-Au NP hydrogel films at low potentials has potential applications in electrochemical and optical sensor development, catalysis, and biological studies.