[Ni(PPh 2NAr 2)2(NCMe)][BF4]2 as an electrocatalyst for H2 production: PPh 2NAr 2 = 1,5-(di(4-(thiophene-3-yl)phenyl)-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane)

Douglas H. Pool, Daniel L DuBois

Research output: Contribution to journalArticle

69 Citations (Scopus)

Abstract

A new cyclic 1,5-diaza-3,7-diphosphacyclooctane ligand was prepared with phenyl substituents on phosphorus and (thiophene-3-yl)phenyl substituents on nitrogen. This ligand reacts with [Ni(CH3CN)6][BF4]2 to form the corresponding [Ni(PPh 2NAr 2)2(NCMe)][BF4]2 complex, 3, which is an active electrocatalyst for H2 production. Kinetic studies indicate that the catalytic rate is first order in catalyst and second order in acid at low concentrations of acid, but at higher acid concentrations the catalytic rate becomes independent of acid concentration. The rate-determining step at high acid concentrations is attributed to the elimination of H2 from a reduced Ni species. The modest overpotential of 280 mV and a turnover frequency of 56 s-1 confirm that 3 is a relatively active catalyst for H2 production in acetonitrile solutions. Oxidation of the pendant thiophene substituents of 3 results in the formation of films on glassy carbon electrode surfaces. However these films are not electroactive, and electrocatalysis of proton reduction is not observed with these modified electrodes.

Original languageEnglish
Pages (from-to)2858-2865
Number of pages8
JournalJournal of Organometallic Chemistry
Volume694
Issue number17
DOIs
Publication statusPublished - Aug 1 2009

Fingerprint

Thiophenes
electrocatalysts
Electrocatalysts
Thiophene
thiophenes
acids
Acids
Electrodes
Ligands
catalysts
Electrocatalysis
ligands
Catalysts
electrodes
glassy carbon
Glassy carbon
Acetonitrile
Phosphorus
acetonitrile
phosphorus

Keywords

  • Catalyst
  • Hydrogen production
  • Nickel

ASJC Scopus subject areas

  • Inorganic Chemistry
  • Organic Chemistry
  • Physical and Theoretical Chemistry
  • Materials Chemistry
  • Biochemistry

Cite this

@article{aa34cf24909a449599bb53066596f462,
title = "[Ni(PPh 2NAr 2)2(NCMe)][BF4]2 as an electrocatalyst for H2 production: PPh 2NAr 2 = 1,5-(di(4-(thiophene-3-yl)phenyl)-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane)",
abstract = "A new cyclic 1,5-diaza-3,7-diphosphacyclooctane ligand was prepared with phenyl substituents on phosphorus and (thiophene-3-yl)phenyl substituents on nitrogen. This ligand reacts with [Ni(CH3CN)6][BF4]2 to form the corresponding [Ni(PPh 2NAr 2)2(NCMe)][BF4]2 complex, 3, which is an active electrocatalyst for H2 production. Kinetic studies indicate that the catalytic rate is first order in catalyst and second order in acid at low concentrations of acid, but at higher acid concentrations the catalytic rate becomes independent of acid concentration. The rate-determining step at high acid concentrations is attributed to the elimination of H2 from a reduced Ni species. The modest overpotential of 280 mV and a turnover frequency of 56 s-1 confirm that 3 is a relatively active catalyst for H2 production in acetonitrile solutions. Oxidation of the pendant thiophene substituents of 3 results in the formation of films on glassy carbon electrode surfaces. However these films are not electroactive, and electrocatalysis of proton reduction is not observed with these modified electrodes.",
keywords = "Catalyst, Hydrogen production, Nickel",
author = "Pool, {Douglas H.} and DuBois, {Daniel L}",
year = "2009",
month = "8",
day = "1",
doi = "10.1016/j.jorganchem.2009.04.010",
language = "English",
volume = "694",
pages = "2858--2865",
journal = "Journal of Organometallic Chemistry",
issn = "0022-328X",
publisher = "Elsevier",
number = "17",

}

TY - JOUR

T1 - [Ni(PPh 2NAr 2)2(NCMe)][BF4]2 as an electrocatalyst for H2 production

T2 - PPh 2NAr 2 = 1,5-(di(4-(thiophene-3-yl)phenyl)-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane)

AU - Pool, Douglas H.

AU - DuBois, Daniel L

PY - 2009/8/1

Y1 - 2009/8/1

N2 - A new cyclic 1,5-diaza-3,7-diphosphacyclooctane ligand was prepared with phenyl substituents on phosphorus and (thiophene-3-yl)phenyl substituents on nitrogen. This ligand reacts with [Ni(CH3CN)6][BF4]2 to form the corresponding [Ni(PPh 2NAr 2)2(NCMe)][BF4]2 complex, 3, which is an active electrocatalyst for H2 production. Kinetic studies indicate that the catalytic rate is first order in catalyst and second order in acid at low concentrations of acid, but at higher acid concentrations the catalytic rate becomes independent of acid concentration. The rate-determining step at high acid concentrations is attributed to the elimination of H2 from a reduced Ni species. The modest overpotential of 280 mV and a turnover frequency of 56 s-1 confirm that 3 is a relatively active catalyst for H2 production in acetonitrile solutions. Oxidation of the pendant thiophene substituents of 3 results in the formation of films on glassy carbon electrode surfaces. However these films are not electroactive, and electrocatalysis of proton reduction is not observed with these modified electrodes.

AB - A new cyclic 1,5-diaza-3,7-diphosphacyclooctane ligand was prepared with phenyl substituents on phosphorus and (thiophene-3-yl)phenyl substituents on nitrogen. This ligand reacts with [Ni(CH3CN)6][BF4]2 to form the corresponding [Ni(PPh 2NAr 2)2(NCMe)][BF4]2 complex, 3, which is an active electrocatalyst for H2 production. Kinetic studies indicate that the catalytic rate is first order in catalyst and second order in acid at low concentrations of acid, but at higher acid concentrations the catalytic rate becomes independent of acid concentration. The rate-determining step at high acid concentrations is attributed to the elimination of H2 from a reduced Ni species. The modest overpotential of 280 mV and a turnover frequency of 56 s-1 confirm that 3 is a relatively active catalyst for H2 production in acetonitrile solutions. Oxidation of the pendant thiophene substituents of 3 results in the formation of films on glassy carbon electrode surfaces. However these films are not electroactive, and electrocatalysis of proton reduction is not observed with these modified electrodes.

KW - Catalyst

KW - Hydrogen production

KW - Nickel

UR - http://www.scopus.com/inward/record.url?scp=67650093828&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=67650093828&partnerID=8YFLogxK

U2 - 10.1016/j.jorganchem.2009.04.010

DO - 10.1016/j.jorganchem.2009.04.010

M3 - Article

AN - SCOPUS:67650093828

VL - 694

SP - 2858

EP - 2865

JO - Journal of Organometallic Chemistry

JF - Journal of Organometallic Chemistry

SN - 0022-328X

IS - 17

ER -