Pyridinic N anchored Ag and Au hybrids for detoxification of organic pollutants

Abstract

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.

Anchoring Pd Nanoparticles with Low Loading on Co,N‐Doped Carbon Framework for the Synergistic Reduction of Nitrophenols

“…Thus the dosage of the catalyst was fixed at 50 μg in the following reactions. Furthermore, the formation of 4‐AP can be monitored through the photoluminescence signal intensity [41,42] . The fluorescence signal of 4‐AP can be observed at 373 nm, which also confirmed the formation of 4‐AP under 300 nm excitation with xenon lamp (Figure 5).…”

“…Furthermore, the formation of 4-AP can be monitored through the photoluminescence signal intensity. [41,42] The fluorescence signal of 4-AP can be observed at 373 nm, which also confirmed the formation of 4-AP under 300 nm excitation with xenon lamp (Figure 5). Then, the reduction of 4-NP catalyzed by Co@NC and Pd/ Co@NC with different weight loading of Pd was shown in Figure 6 and Figure S3.…”

Exfoliated MXene–AuNPs hybrid in sensing and multiple catalytic hydrogenation reactions

“…Similarly, the combination of MXene and CIT-AuNPs exhibits an 8.6X fold decrease in the K value relative to CIT-AuNPs. The observed significant reduction may be attributed to fewer functional groups, such as hydroxyl and carboxyl, on the surface of AuNPs that primarily interact with MXene [53]. Although the hybrid synthesized with Au salt direct reduction on MXene surface shows the fastest reaction, it isn't easy to control the growth of NPs in the reaction solution, more studies are possibly needed to obtain reproducible results.…”

Engineering Kirigami Frameworks Toward Real‐World Applications

“…Furthermore, kirigami has the potential to foster the development of energy‐efficient and eco‐friendly devices. For instance, the exceptional stretchability, adaptability, and conformability of kirigami could be leveraged to design smart building envelops capable of self‐cooling [ 140,147,148 ] (Figure 8C), large‐scale structures that facilitate water collection in open environments, [ 37,149 ] and light‐responsive solar panels that can automatically track sunlight to maximum the efficiency. [ 150 ] Additionally, by integrating physical intelligence into kirigami‐based metamaterials and constructing them using biodegradable materials, one can reduce the electronic waste in certain devices, such as soft robotics and medical devices, steering us toward a more sustainable future.…”