In this study, macroporous graphene aerogels (GAs) were synthesized by chemical reduction of graphene oxide sheets and were used as a support material for in situ synthesis of conductive poly(para-phenylenediamine) (p(p-PDA)). The in situ synthesis of p(p-PDA) in GA was carried out by using a simple oxidation polymerization technique. Moreover, the prepared conductive p(p-PDA) polymers in the networks of GAs were doped with various types of acids such as hydrochloric acid (HCl), nitric acid (HNO₃), sulfuric acid (H₂SO₄), phosphoric acid (H₃PO₄), respectively. The prepared GA and different acid-doped forms as GA/p(p-PDA) composites were characterized by FT-IR, TGA, and conductivity measurements. The observed FT-IR peaks at 1574 cm⁻¹, and 1491 cm⁻¹, for stretching deformations of quinone and benzene, respectively, confirmed the in situ synthesis of P(p-PDA) polymers within GAs. The conductivity of GAs with 2.17 × 10⁻⁴ ± 3.15 × 10⁻⁵ S·cm⁻¹ has experienced an approximately 250-fold increase to 5.16 × 10⁻² ± 2.72 × 10⁻³ S·cm⁻¹ after in situ synthesis of p(p-PDA) polymers and with HCl doping. Conductivity values for different types of acid-doped GA/p(p-PDA) composites were compared with the bare p(p-PDA) and their undoped forms. Moreover, the changes in the conductivity of GA and GA/p(p-PDA) composites upon CO₂ gas exposure were compared and their sensory potential in terms of response and sensitivity, along with reusability in CO₂ detection, were evaluated.

中文翻译：

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用于原位合成导电聚对苯二胺聚合物的石墨烯气凝胶及其传感器应用。


在这项研究中，通过氧化石墨烯片的化学还原合成了大孔石墨烯气凝胶（GA），并将其用作导电聚对苯二胺（p（p-PDA））原位合成的支撑材料。采用简单的氧化聚合技术在GA中原位合成了p(p-PDA)。此外，在GA网络中制备的导电p(p-PDA)聚合物中掺杂了各种类型的酸，例如盐酸(HCl)、硝酸(HNO ₃ )、硫酸(H ₂ SO ₄ )、磷酸(H ₃ PO ₄ )。通过 FT-IR、TGA 和电导率测量对制备的 GA 和不同酸掺杂形式的 GA/p(p-PDA) 复合材料进行了表征。观察到的 FT-IR 峰分别位于 1574 cm ^-1和 1491 cm ^-1处，分别表示醌和苯的拉伸变形，证实了 GA 内 P(p-PDA) 聚合物的原位合成。原位合成后，GA的电导率为2.17 × 10 ^-4 ± 3.15 × 10 ^-5 S·cm ^-1 ，增加了约250倍，达到5.16 × 10 ^-2 ± 2.72 × 10 ^-3 S·cm ^-1 p(p-PDA) 聚合物和 HCl 掺杂。将不同类型的酸掺杂 GA/p(p-PDA) 复合材料的电导率值与裸露的 p(p-PDA) 及其未掺杂形式进行比较。此外，还比较了GA和GA/p(p-PDA)复合材料在接触CO ₂气体后电导率的变化，并评估了它们在响应和灵敏度方面的传感潜力以及CO ₂检测中的可重复使用性。