The development of a highly reusable, non-toxic catalyst for the effective removal of 4-nitrophenol (4-NP) from marine water is a key challenge due to its diverse effects on living organisms. Herein, in situ green fabricated pyridinic N anchored Ag₂O/Au decorated porous silica (CG-Ag₂O/Au-SiO₂) using spent coffee grounds (CG) powder is introduced as a reusable catalyst to mitigate 4-NP, Methylene blue (MB), Rhodamine 6G (R6G) and their mixture in the spiked deionized, river and marine water samples. Exceptionally high structural activity and excellent reusability of catalysts up to 15 cycles have been demonstrated due to the accessibility of a large number of active sites from pyridinic N-anchored Ag₂O and Au particle surfaces. CG-Ag₂O/Au-SiO₂ with the lower Ag and Au contents of 0.59 and 0.11 wt% (ICP-MS) of active catalytic sites exhibit a superior activity parameter of 6000 s⁻¹ g⁻¹ (4-NP), 6357 s⁻¹ g⁻¹ (MB), and 2892 s⁻¹ g⁻¹ (R6G) than chemically synthesized and reported, bare and hybrid structures. Furthermore, the CG-Ag₂O/Au-SiO₂ shows excellent stability in marine water with promising reusability performance (≈93% after 15 successive cycles). Density functional theory (DFT) studies reveal that the observed high catalytic efficiency originates from the pyridinic N presence on the Ag₂O/Au structures.

开发一种高度可重复使用、无毒的催化剂以有效去除海水中的 4-硝基苯酚 (4-NP) 是一项关键挑战，因为它对生物体具有多种影响。在此，使用废咖啡渣 (CG) 粉末原位绿色制备的吡啶 N 锚定 Ag ₂ O/Au 装饰多孔二氧化硅 (CG-Ag ₂ O/Au-SiO ₂ ) 作为可重复使用的催化剂，以减轻 4-NP、亚甲基蓝色 (MB)、罗丹明 6G (R6G) 及其混合物在加标的去离子水、河流和海水样品中。_{由于吡啶 N 锚定的 Ag 2} O 和 Au 颗粒表面的大量活性位点的可及性，已经证明了催化剂具有极高的结构活性和高达 15 次循环的出色可重复使用性。CG-Ag₂ O/Au-SiO ₂具有较低的 Ag 和 Au 含量为 0.59 和 0.11 wt% (ICP-MS) 的活性催化位点表现出优异的活性参数，即 6000 s ^-1  g ^-1 (4-NP)、6357 s ^-1  g ^-1 (MB) 和 2892 s ^-1  g ^-1 (R6G) 比化学合成和报道的裸结构和混合结构。此外，CG-Ag ₂ O/Au-SiO ₂在海水中表现出优异的稳定性，具有良好的可重复使用性能（连续 15 次循环后约为 93%）。密度泛函理论 (DFT) 研究表明，观察到的高催化效率源于 Ag _{2上存在的吡啶 N}O/Au 结构。