Galvanic exchange as a novel method for carbon nitride supported coag catalyst synthesis for oxygen reduction and carbon dioxide conversion

Roshan Nazir, Anand Kumar, Sardar Ali, Mohammed Ali Saleh Saad, Mohammed J. Al-Marri

Research output: Contribution to journalArticle

Abstract

A bimetallic alloy of CoAg nanoparticles (NPs) on a carbon nitride (CN) surface was synthesized using a galvanic exchange process for the oxygen reduction reaction (ORR) and carbon dioxide electrocatalytic conversion. The reduction potential of cobalt is ([Co2+(aq) + 2e → Co(s)], −0.28 eV) is smaller than that of Ag ([Ag+(aq) + e → Ag(s)], 0.80 eV), which makes Co(0) to be easily replaceable by Ag+ ions. Initially, Co NPs (nanoparticles) were synthesized on a CN surface via adsorbing the Co2+ precursor on the surface of CN and subsequently reducing them with NaBH4 to obtain Co/CN NP. The Co NPs on the surface of CN were then subjected to galvanic exchange, where the sacrificial Co atoms were replaced by Ag atoms. As the process takes place on a solid surface, only the partial replacement of Co by Ag was possible generating CoAg/CN NPs. Synthesized CoAg/CN bimetallic alloy were characterized using different techniques such as powder x-ray diffraction (PXRD), x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and electron diffraction spectroscopy (EDS) to confirm the product. Both the catalysts, Co/CN and CoAg/CN, were evaluated for oxygen reduction reaction in 1M KOH solution and carbon dioxide conversion in 0.5 M KHCO3. In the case of ORR, the CoAg/CN was found to be an efficient electrocatalyst with the onset potential of 0.93 V, which is comparable to commercially available Pt/C having Eonset at 0.91 V. In the electrocatalytic conversion of CO2, the CoAg/CN showed better performance than Co/CN. The cathodic current decreased dramatically below −0.9V versus Ag/AgCl indicating the high conversion of CO2.

Original languageEnglish
Article number860
JournalCatalysts
Volume9
Issue number10
DOIs
Publication statusPublished - Oct 2019

Fingerprint

carbon nitrides
Carbon nitride
dioxides
Catalyst supports
Carbon Dioxide
carbon dioxide
Carbon dioxide
Oxygen
catalysts
oxygen
synthesis
Nanoparticles
nanoparticles
cyanogen
Ion exchange
X rays
Atoms
electrocatalysts
Electrocatalysts
Photoelectron spectroscopy

Keywords

  • AgCo catalyst
  • Carbon dioxide conversion
  • Carbon nitride
  • Galvanic exchange
  • Oxygen reduction reaction

ASJC Scopus subject areas

  • Catalysis
  • Physical and Theoretical Chemistry

Cite this

Galvanic exchange as a novel method for carbon nitride supported coag catalyst synthesis for oxygen reduction and carbon dioxide conversion. / Nazir, Roshan; Kumar, Anand; Ali, Sardar; Saad, Mohammed Ali Saleh; Al-Marri, Mohammed J.

In: Catalysts, Vol. 9, No. 10, 860, 10.2019.

Research output: Contribution to journalArticle

@article{c481d53a95e14941b705b6eb6351a21c,
title = "Galvanic exchange as a novel method for carbon nitride supported coag catalyst synthesis for oxygen reduction and carbon dioxide conversion",
abstract = "A bimetallic alloy of CoAg nanoparticles (NPs) on a carbon nitride (CN) surface was synthesized using a galvanic exchange process for the oxygen reduction reaction (ORR) and carbon dioxide electrocatalytic conversion. The reduction potential of cobalt is ([Co2+(aq) + 2e− → Co(s)], −0.28 eV) is smaller than that of Ag ([Ag+(aq) + e− → Ag(s)], 0.80 eV), which makes Co(0) to be easily replaceable by Ag+ ions. Initially, Co NPs (nanoparticles) were synthesized on a CN surface via adsorbing the Co2+ precursor on the surface of CN and subsequently reducing them with NaBH4 to obtain Co/CN NP. The Co NPs on the surface of CN were then subjected to galvanic exchange, where the sacrificial Co atoms were replaced by Ag atoms. As the process takes place on a solid surface, only the partial replacement of Co by Ag was possible generating CoAg/CN NPs. Synthesized CoAg/CN bimetallic alloy were characterized using different techniques such as powder x-ray diffraction (PXRD), x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and electron diffraction spectroscopy (EDS) to confirm the product. Both the catalysts, Co/CN and CoAg/CN, were evaluated for oxygen reduction reaction in 1M KOH solution and carbon dioxide conversion in 0.5 M KHCO3. In the case of ORR, the CoAg/CN was found to be an efficient electrocatalyst with the onset potential of 0.93 V, which is comparable to commercially available Pt/C having Eonset at 0.91 V. In the electrocatalytic conversion of CO2, the CoAg/CN showed better performance than Co/CN. The cathodic current decreased dramatically below −0.9V versus Ag/AgCl indicating the high conversion of CO2.",
keywords = "AgCo catalyst, Carbon dioxide conversion, Carbon nitride, Galvanic exchange, Oxygen reduction reaction",
author = "Roshan Nazir and Anand Kumar and Sardar Ali and Saad, {Mohammed Ali Saleh} and Al-Marri, {Mohammed J.}",
year = "2019",
month = "10",
doi = "10.3390/catal9100860",
language = "English",
volume = "9",
journal = "Catalysts",
issn = "2073-4344",
publisher = "Multidisciplinary Digital Publishing Institute (MDPI)",
number = "10",

}

TY - JOUR

T1 - Galvanic exchange as a novel method for carbon nitride supported coag catalyst synthesis for oxygen reduction and carbon dioxide conversion

AU - Nazir, Roshan

AU - Kumar, Anand

AU - Ali, Sardar

AU - Saad, Mohammed Ali Saleh

AU - Al-Marri, Mohammed J.

PY - 2019/10

Y1 - 2019/10

N2 - A bimetallic alloy of CoAg nanoparticles (NPs) on a carbon nitride (CN) surface was synthesized using a galvanic exchange process for the oxygen reduction reaction (ORR) and carbon dioxide electrocatalytic conversion. The reduction potential of cobalt is ([Co2+(aq) + 2e− → Co(s)], −0.28 eV) is smaller than that of Ag ([Ag+(aq) + e− → Ag(s)], 0.80 eV), which makes Co(0) to be easily replaceable by Ag+ ions. Initially, Co NPs (nanoparticles) were synthesized on a CN surface via adsorbing the Co2+ precursor on the surface of CN and subsequently reducing them with NaBH4 to obtain Co/CN NP. The Co NPs on the surface of CN were then subjected to galvanic exchange, where the sacrificial Co atoms were replaced by Ag atoms. As the process takes place on a solid surface, only the partial replacement of Co by Ag was possible generating CoAg/CN NPs. Synthesized CoAg/CN bimetallic alloy were characterized using different techniques such as powder x-ray diffraction (PXRD), x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and electron diffraction spectroscopy (EDS) to confirm the product. Both the catalysts, Co/CN and CoAg/CN, were evaluated for oxygen reduction reaction in 1M KOH solution and carbon dioxide conversion in 0.5 M KHCO3. In the case of ORR, the CoAg/CN was found to be an efficient electrocatalyst with the onset potential of 0.93 V, which is comparable to commercially available Pt/C having Eonset at 0.91 V. In the electrocatalytic conversion of CO2, the CoAg/CN showed better performance than Co/CN. The cathodic current decreased dramatically below −0.9V versus Ag/AgCl indicating the high conversion of CO2.

AB - A bimetallic alloy of CoAg nanoparticles (NPs) on a carbon nitride (CN) surface was synthesized using a galvanic exchange process for the oxygen reduction reaction (ORR) and carbon dioxide electrocatalytic conversion. The reduction potential of cobalt is ([Co2+(aq) + 2e− → Co(s)], −0.28 eV) is smaller than that of Ag ([Ag+(aq) + e− → Ag(s)], 0.80 eV), which makes Co(0) to be easily replaceable by Ag+ ions. Initially, Co NPs (nanoparticles) were synthesized on a CN surface via adsorbing the Co2+ precursor on the surface of CN and subsequently reducing them with NaBH4 to obtain Co/CN NP. The Co NPs on the surface of CN were then subjected to galvanic exchange, where the sacrificial Co atoms were replaced by Ag atoms. As the process takes place on a solid surface, only the partial replacement of Co by Ag was possible generating CoAg/CN NPs. Synthesized CoAg/CN bimetallic alloy were characterized using different techniques such as powder x-ray diffraction (PXRD), x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and electron diffraction spectroscopy (EDS) to confirm the product. Both the catalysts, Co/CN and CoAg/CN, were evaluated for oxygen reduction reaction in 1M KOH solution and carbon dioxide conversion in 0.5 M KHCO3. In the case of ORR, the CoAg/CN was found to be an efficient electrocatalyst with the onset potential of 0.93 V, which is comparable to commercially available Pt/C having Eonset at 0.91 V. In the electrocatalytic conversion of CO2, the CoAg/CN showed better performance than Co/CN. The cathodic current decreased dramatically below −0.9V versus Ag/AgCl indicating the high conversion of CO2.

KW - AgCo catalyst

KW - Carbon dioxide conversion

KW - Carbon nitride

KW - Galvanic exchange

KW - Oxygen reduction reaction

UR - http://www.scopus.com/inward/record.url?scp=85074011463&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85074011463&partnerID=8YFLogxK

U2 - 10.3390/catal9100860

DO - 10.3390/catal9100860

M3 - Article

AN - SCOPUS:85074011463

VL - 9

JO - Catalysts

JF - Catalysts

SN - 2073-4344

IS - 10

M1 - 860

ER -