Structurally-Tuned Nitrogen-Doped Cerium Oxide Exhibits Exceptional Regenerative Free Radical Scavenging Activity in Polymer Electrolytes

Prabhakaran, Venkateshkumar; Ramani, Vijay

doi:10.1149/2.004401jes

Cited by 33 publications

(20 citation statements)

References 74 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although a high value of K m indicates low affinity of VE CeO 2 NPs towards paraoxon, this observation suggests that the weak binding of organophosphates may help in a facile elimination of the product from the reaction sites. By using the standard molar concentrations of nanoparticles, the turnover number ( k cat ) and catalytic efficiency ( k cat / K m ) were found to be 5.42 s −1 and 3.44×10 2 m −1 s −1 , respectively . These values are significantly higher than those reported for some metal complexes, and are comparable to native PTE enzyme .…”

Section: Methodsmentioning

confidence: 72%

Vacancy‐Engineered Nanoceria: Enzyme Mimetic Hotspots for the Degradation of Nerve Agents

2015

View full text Add to dashboard Cite

Organophosphorus-based nerve agents, such as paraoxon, parathion, and malathion, inhibit acetylcholinesterase, which results in paralysis, respiratory failure, and death. Bacteria are known to use the enzyme phosphotriesterase (PTE) to break down these compounds. In this work, we designed vacancy-engineered nanoceria (VE CeO2 NPs) as PTE mimetic hotspots for the rapid degradation of nerve agents. We observed that the hydrolytic effect of the nanomaterial is due to the synergistic activity between both Ce(3+) and Ce(4+) ions located in the active site-like hotspots. Furthermore, the catalysis by nanoceria overcomes the product inhibition generally observed for PTE and small molecule-based PTE mimetics.

show abstract

Section: Methodsmentioning

confidence: 72%

Vacancy‐Engineered Nanoceria: Enzyme Mimetic Hotspots for the Degradation of Nerve Agents

2015

View full text Add to dashboard Cite

show abstract

“…[97,98] The presence of active Ce 3+ and oxygen vacancies in the CeO 2 lattice are the primary reason for being an effective scavenging of ROS. [100][101][102] The regenerative ROS scavenging ability of CeO 2 has been previously explored and CeO 2 has been used as an antioxidant both in biological applications [97] and in mitigating oxidative degradation of the membrane in a PEMFC. [22,93,[103][104][105][106] The radical scavenging mechanism of CeO 2 is summarized in following Equations 3 generation.…”

Section: Experimental Spectroscopy Analysismentioning

confidence: 99%

Iron‐Free Cathode Catalysts for Proton‐Exchange‐Membrane Fuel Cells: Cobalt Catalysts and the Peroxide Mitigation Approach

et al. 2019

Self Cite

View full text Add to dashboard Cite

High‐performance and inexpensive platinum‐group‐metal (PGM)‐free catalysts for the oxygen reduction reaction (ORR) in challenging acidic media are crucial for proton‐exchange‐membrane fuel cells (PEMFCs). Catalysts based on Fe and N codoped carbon (Fe–N–C) have demonstrated promising activity and stability. However, a serious concern is the Fenton reactions between Fe2+ and H2O2 generating active free radicals, which likely cause degradation of the catalysts, organic ionomers within electrodes, and polymer membranes used in PEMFCs. Alternatively, Co–N–C catalysts with mitigated Fenton reactions have been explored as a promising replacement for Fe and PGM catalysts. Therefore, herein, the focus is on Co–N–C catalysts for the ORR relevant to PEMFC applications. Catalyst synthesis, structure/morphology, activity and stability improvement, and reaction mechanisms are discussed in detail. Combining experimental and theoretical understanding, the aim is to elucidate the structure–property correlations and provide guidance for rational design of advanced Co catalysts with a special emphasis on atomically dispersed single‐metal‐site catalysts. In the meantime, to reduce H2O2 generation during the ORR on the Co catalysts, potential strategies are outlined to minimize the detrimental effect on fuel cell durability.

show abstract

“…30 DFT calculations suggest that in contrast to N doped TiO 2 , the band edges in N-CeO 2 are lowered with respect to CeO 2 on both sides of the energy gap. 33 33 …”

Section: N-doped Tio 2 and Ceomentioning

confidence: 99%

Metal oxynitrides as emerging materials with photocatalytic and electronic properties

Fuertes

2015

Mater. Horiz.

141

View full text Add to dashboard Cite

Oxynitrides of transition metals, alkaline earth metals and rare earth metals are intensively investigated as a group of materials to expand and tune the properties of oxides. The differences in polarizability, electronegativity and anion charge of nitrogen and oxygen induce changes in the physical and chemical properties of oxides by nitrogen introduction. The effects on properties arise from the higher covalency of the metal-nitrogen bond and the changes in the energies of electronic levels, and are important in slightly doped nitrogen metal oxides as in stoichiometric oxynitrides. More intense recent progress in oxynitride research has been made in some specific fields such as photocatalysis in water splitting and other processes as the observed small band gaps lead to activity in the visible light range. The stabilization of new perovskite oxynitrides, with the oxidation states of cations tuned by N/O stoichiometry, has led to new magnetic and dielectric materials. The lower electronegativity of nitrogen and larger crystal field splitting induced by N 3À shifts the emission wavelengths of phosphors to the red, and oxynitridosilicates have been investigated as components of white LEDs.

show abstract

Structurally-Tuned Nitrogen-Doped Cerium Oxide Exhibits Exceptional Regenerative Free Radical Scavenging Activity in Polymer Electrolytes

Cited by 33 publications

References 74 publications

Vacancy‐Engineered Nanoceria: Enzyme Mimetic Hotspots for the Degradation of Nerve Agents

Vacancy‐Engineered Nanoceria: Enzyme Mimetic Hotspots for the Degradation of Nerve Agents

Iron‐Free Cathode Catalysts for Proton‐Exchange‐Membrane Fuel Cells: Cobalt Catalysts and the Peroxide Mitigation Approach

Metal oxynitrides as emerging materials with photocatalytic and electronic properties

Contact Info

Product

Resources

About