Identification and Regulation of Active Sites on Nanodiamonds: Establishing a Highly Efficient Catalytic System for Oxidation of Organic Contaminants

Abstract

Nanodiamonds exhibit great potential as green catalysts for remediation of organic contaminants. However, the specific active site and corresponding oxidative mechanism are unclear, which retard further developments of high‐performance catalysts. Here, an annealing strategy is developed to accurately regulate the content of ketonic carbonyl groups on nanodiamonds; meanwhile other structural characteristics of nanodiamonds remain almost unchanged. The well‐defined nanodiamonds with well‐controlled ketonic carbonyl groups exhibit excellent catalytic activity in activation of peroxymonosulfate for oxidation of organic pollutants. Based on the semi‐quantitative and quantitative correlations of ketonic carbonyl groups and the reaction rate constants, it is conclusively determined that ketonic carbonyl groups are the catalytically active sites. Different from conventional oxidative systems, reactive oxygen species in nanodiamonds@peroxymonosulfate system are revealed to be singlet oxygen with high selectivity, which can effectively oxidize and mineralize the target contaminants. Impressively, the singlet‐oxygen‐mediated oxidation system significantly outperforms the classical radicals‐based oxidation system in remediation of actual wastewater. This work not only provides a valuable insight for the design of new nanocarbon catalysts with abundant active sites but also establishes a very promising catalytic oxidation system for the green remediation of actual contaminated water.

Non-Monotonic Trends of Hydrogen Adsorption on Single Atom Doped g-C3N4

“…We expect that this study could also be valuable for many HER-related applications such as CO 2 and N 2 capture and utilization [5,53]. Also, it is expected that similar trends could be found in other reactions (e.g., oxygen reduction [54][55][56][57], oxygen evolution [58], and organic oxidation [59][60][61]) and in various types of advanced under-coordinated material systems [62][63][64][65][66][67][68][69][70][71].…”

Nanoclay-modulated oxygen vacancies of metal oxide

“…To confirm the reactive oxygen species, the radical scavenger tests were conducted using tert-butyl alcohol (TBA) and methanol ( Supplementary Figure 20). Methanol exhibited an obvious inhibitory effect on the degradation of Orange II, due to the scavenge of sulfate radical by methanol (MeOH) 55,56 . The possible mechanism of the highly efficient catalyst could be summarized (Supplementary Note 1).…”

One‐Step Hydrothermal Method to Prepare Flower‐Like QDs CdSe‐Loaded BiOCl Sheets as a Promising Tool for Photodegradation

“…The different trapping agent was added during the photodegrading process in order to investigate the photocatalytic oxidation mechanism . As shown in Figure , the photodegradation of 20 mg/L RhB with 10 wt% CdSe‐BiOCl particles was nearly not influenced by addition of 1 mmol IPA (a quencher of •OH).…”