RESUMEN
The increasing use of nanomaterials in consumer products is expected to lead to environmental contamination sometime soon. As water pollution is a pressing issue that threatens human survival and impedes the promotion of human health, the search for adsorbents for removing newly identified contaminants from water has become a topic of intensive research. The challenges in the recyclability of contaminated water continue to campaign the development of highly reusable catalysts. Although exfoliated 2D MXene sheets have demonstrated the capability towards water purification, a significant challenge for removing some toxic organic molecules remains a challenge due to a need for metal-based catalytic properties owing to their rapid response. In the present study, we demonstrate the formation of hybrid structure AuNPs@MXene (Mo2CTx) during the sensitive detection of Au nanoparticle through MXene sheets without any surface modification, and subsequently its applications as an efficient catalyst for the degradation of 4-nitrophenol (4-NP), methyl orange (MO), and methylene blue (MB). The hybrid structure (AuNPs@MXene) reveals remarkable reusability for up to eight consecutive cycles, with minimal reduction in catalytic efficiency and comparable apparent reaction rate constant (Kapp) values for 4-NP, MB, and MO, compared to other catalysts reported in the literature.
RESUMEN
The task of creating a remarkably stable and effective electrochemical catalyst for efficient hydrogen evolution is arduous, primarily due to the multitude of factors that need to be taken into account for the industrial utilization of Pt. In this work, hybrid formation through in-situ reduction of Pt onto biogenic porous silica (Pt-SiO2) is tested for its use as an efficient catalyst for hydrogen production. Exceptionally high electrocatalytic activity and excellent reusability of catalysts up to 200 cycles have been demonstrated. Pt-SiO2 with low Pt content of 0.48 to 0.82 at% with active catalytic sites exhibit superior catalytic activity with a Tafel slope of 22 mV dec-1 and an overpotential of 28 mV (vs. RHE at 10 mA cm-2) as compared to the Pt wire and previously reported bare Pt-SiO2 (0.65 at% and 0.48 at% of Pt), and hybrid (Pt/Ag) structures formed onto two different biogenic porous SiO2 substrates. The best catalytic performance of the Pt1Ag3 cluster, representing a low Pt concentration, has been validated by Density Functional Theory (DFT) calculations. Here, the high production from the Pt1Ag3 cluster is assigned to the mutual synergistic effect between Pt/Ag atoms. The Pt atoms transfer the excess charge to the nearest Ag neighbors inside the cluster, facilitating hydrogen diffusion on the activated sites. These important findings authenticate the superior hydrogen production at reduced Pt concentration on amine-functionalized biogenic porous silica.