| Autor: |
Mallick L; Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas New Delhi 110016, India., Annadata HV; Beamline Development and Application Section, Bhabha Atomic Research Center, Trombay Mumbai 400085, India., Chakraborty B; Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas New Delhi 110016, India. |
| Jazyk: |
angličtina |
| Zdroj: |
ACS applied materials & interfaces [ACS Appl Mater Interfaces] 2024 Jun 26; Vol. 16 (25), pp. 32385-32393. Date of Electronic Publication: 2024 Jun 14. |
| DOI: |
10.1021/acsami.4c04466 |
| Abstrakt: |
The pronounced conductivity of tin dioxide (SnO 2 ) nanoparticles makes it an ideal multifunctional electrode material, while the challenge is to stabilize the quantum dot (QD) SnO 2 nanocore in water. An Anderson-type polyoxomolybdate, (NH 4 ) 6 [Mo 7 O 24 ], is employed as an inorganic ligand to stabilize a ca. 6 nm SnO 2 QD (Mo x @SnO 2 ). X-ray scattering and diffraction studies confirm the tetragonal SnO 2 nanocore in Mo x @SnO 2 . Elemental analyses are in good agreement with the mass spectrometric detection of the [Mo 7 O 24 ] 6- cluster present in Mo x @SnO 2 . The ionic POMs attached to the SnO 2 surface through [Mo-O-Sn] covalent linkages have been established by surface zeta potential, shift of the [Mo = O] t Raman vibration, and extended X-ray absorption fine structure (EXAFS) analyses. The presence of the [Mo 7 O 24 ] 6- cluster in the Mo x @SnO 2 is responsible for the remarkable aqueous stability of Mo x @SnO 2 in the pH range of 3-9. Dominant oxygen vacancy in the SnO 2 core, identified by EXAFS data and the anisotropic electron paramagnetic resonance (EPR) signals ( g ∼ 2.4 and 1.9), results in facile electronic conduction in Mo x @SnO 2 while being deposited on the electrode surface. Mo x @SnO 2 acts as an active catalyst for the electrocatalytic nitrate reduction (eNOR) to ammonia with 94% faradaic efficiency (FE) at -0.2 V vs RHE and a yield rate of 28.9 mg h -1 cm -2 . The stability of Mo x @SnO 2 in acidic pH provides scope to reuse the Mo x @SnO 2 electrode at least four times with notable NH 3 selectivity and a superior production rate (239.06 mmol g -1 (cat) h -1 ). This study demonstrates the essential role of POM in stabilizing SnO 2 QD, harnessing its electrochemical activity toward electrocatalytic ammonia production. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
|
