A green synthesized gold-catalyst (PDA-g-C₃N₄/Au) for highly efficient reduction of nitroaromatics by NaBH₄ was proposed. Polydopamine (PDA) served as the reductant and stabilizer for AuNPs reduction, avoiding the use of chemical reductant and stabilizer that may result in secondary contamination. g-C₃N₄ not only acted as the support but also provided compatibility for AuNPs deposition, enhancing the stability and deposition of AuNPs, which improved the catalytic activity. Different experimental parameters including the amount of Au loading, concentration of NaBH₄, and dosage of catalyst were studied. Results showed that PDA-g-C₃N₄/Au₍₃₎ revealed higher catalytic activity with a rate constant of 0.0514 s⁻¹ and TOF of 545.60 h⁻¹ for 4-NP reduction. In addition, the catalyst was highly efficient in reduction of other nitroaromatics and the reduction rates of these compounds were found as the sequence: methyl orange > 2-nitrophenol > 2, 4-dinitrophenol > Erichrome Black T > Congo red. Moreover, the PDA-g-C₃N₄/Au₍₃₎ catalyst kept high stability and excellent conversion efficiency over ten reduction cycles. The practical application on different real water samples suggests that this Au catalyst has promising application in environmental water purification. The simple and green synthetic Au catalyst expands the range of application and provides potential application on environmental remediation.

提出了用于NaBH ₄高效还原硝基芳烃的绿色合成金催化剂（PDA-gC ₃ N ₄ / Au）。聚多巴胺（PDA）用作还原AuNPs的还原剂和稳定剂，避免使用可能导致二次污染的化学还原剂和稳定剂。gC ₃ N ₄不仅充当载体，还为AuNPs的沉积提供了相容性，增强了AuNPs的稳定性和沉积，从而改善了催化活性。研究了不同的实验参数，包括Au的添加量，NaBH _4的浓度和催化剂的用量。结果表明，PDA-gC ₃ N ₄/ Au _（3）显示出较高的催化活性，其速率常数为0.0514 s ^-1和TOF为545.60 h ^-1以减少4-NP。此外，该催化剂在还原其他硝基芳烃方面非常高效，并且发现这些化合物的还原速率为以下顺序：甲基橙> 2-硝基苯酚> 2，4，4-二硝基苯酚> Erichrome Black T>刚果红。此外，PDA-gC ₃ N ₄ / Au _（3）在十个还原循环中，该催化剂保持了高稳定性和出色的转化效率。在不同的真实水样品上的实际应用表明，该Au催化剂在环境水净化中具有广阔的应用前景。简单而绿色的合成金催化剂扩大了应用范围，并为环境修复提供了潜在的应用。