The Different Roles of Water in Photocatalytic DeNOx Mechanisms on TiO2: A Basis for Engineering Nitrate Selectivity?

Lu Yang; Amer Hakki; Fazhou Wang; Donald E. Macphee

doi:10.1021/acsami.7b01989

The Different Roles of Water in Photocatalytic DeNOx Mechanisms on TiO2: A Basis for Engineering Nitrate Selectivity?

Lu Yang, Amer Hakki, Fazhou Wang, Donald E. Macphee

Chemistry

Research output: Contribution to journal › Article › peer-review

35 Citations (Scopus)

20 Downloads (Pure)

Abstract

The nitrate selectivity of TiO2 has important consequences for its efficiency as a NOx depollution photocatalyst. Most emphasis is typically given to photocatalyst activity, a measure of the rate at which NOx concentrations are reduced, but a reduction in NOx concentration (mainly NO + NO2) is not necessarily a reduction in atmospheric NO2 concentration because the catalytic process itself generates NO2. With NO2 being considerably more toxic than NO, more emphasis on nitrate selectivity, a measure of the NOx conversion to nitrate, and how to maximise it, should be given in engineering photocatalytic systems for improved urban air quality. This study, on the importance of adsorbed water in the photocatalytic oxidation of NOx, has identified important correlations which differentiate the role that water plays in the oxidation of NO and NO2. This observation is significant and offers insights into controlling nitrate selectivity on TiO2 and the potential for increased effectiveness in environmental photocatalyst applications.

Original language	English
Pages (from-to)	17034-17041
Number of pages	8
Journal	ACS Applied Materials & Interfaces
Volume	9
Issue number	20
Early online date	5 May 2017
DOIs	https://doi.org/10.1021/acsami.7b01989
Publication status	Published - 24 May 2017

Bibliographical note

The authors gratefully acknowledge funding from the UK Engineering and Physical
Sciences Research Council (Grant Ref: EP/M003299/1) and the Natural Science Foundation of China (No. 51461135005) International Joint Research Project (EPSRC-NSFC).

Keywords

supported TiO2
synthesis conditions
adsorbed water
NOx
nitrate selectivity

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

Access to Document

10.1021/acsami.7b01989Licence: Unspecified

Accepted Manuscript The Different Roles of Water in Photocatalytic DeNOx
This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Materials and Interfaces, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see 10.1021/acsami.7b01989
Accepted author manuscript, 2.06 MBLicence: Unspecified

Cite this

@article{42a5cd937d004ed0bf81ee9bd5aa6433,

title = "The Different Roles of Water in Photocatalytic DeNOx Mechanisms on TiO2: A Basis for Engineering Nitrate Selectivity?",

abstract = "The nitrate selectivity of TiO2 has important consequences for its efficiency as a NOx depollution photocatalyst. Most emphasis is typically given to photocatalyst activity, a measure of the rate at which NOx concentrations are reduced, but a reduction in NOx concentration (mainly NO + NO2) is not necessarily a reduction in atmospheric NO2 concentration because the catalytic process itself generates NO2. With NO2 being considerably more toxic than NO, more emphasis on nitrate selectivity, a measure of the NOx conversion to nitrate, and how to maximise it, should be given in engineering photocatalytic systems for improved urban air quality. This study, on the importance of adsorbed water in the photocatalytic oxidation of NOx, has identified important correlations which differentiate the role that water plays in the oxidation of NO and NO2. This observation is significant and offers insights into controlling nitrate selectivity on TiO2 and the potential for increased effectiveness in environmental photocatalyst applications.",

keywords = "supported TiO2, synthesis conditions, adsorbed water, NOx, nitrate selectivity",

author = "Lu Yang and Amer Hakki and Fazhou Wang and Macphee, {Donald E.}",

note = "The authors gratefully acknowledge funding from the UK Engineering and Physical Sciences Research Council (Grant Ref: EP/M003299/1) and the Natural Science Foundation of China (No. 51461135005) International Joint Research Project (EPSRC-NSFC). ",

year = "2017",

month = may,

day = "24",

doi = "10.1021/acsami.7b01989",

language = "English",

volume = "9",

pages = "17034--17041",

journal = "ACS Applied Materials & Interfaces",

issn = "1944-8244",

publisher = "American Chemical Society",

number = "20",

}

TY - JOUR

T1 - The Different Roles of Water in Photocatalytic DeNOx Mechanisms on TiO2

T2 - A Basis for Engineering Nitrate Selectivity?

AU - Yang, Lu

AU - Hakki, Amer

AU - Wang, Fazhou

AU - Macphee, Donald E.

N1 - The authors gratefully acknowledge funding from the UK Engineering and Physical Sciences Research Council (Grant Ref: EP/M003299/1) and the Natural Science Foundation of China (No. 51461135005) International Joint Research Project (EPSRC-NSFC).

PY - 2017/5/24

Y1 - 2017/5/24

N2 - The nitrate selectivity of TiO2 has important consequences for its efficiency as a NOx depollution photocatalyst. Most emphasis is typically given to photocatalyst activity, a measure of the rate at which NOx concentrations are reduced, but a reduction in NOx concentration (mainly NO + NO2) is not necessarily a reduction in atmospheric NO2 concentration because the catalytic process itself generates NO2. With NO2 being considerably more toxic than NO, more emphasis on nitrate selectivity, a measure of the NOx conversion to nitrate, and how to maximise it, should be given in engineering photocatalytic systems for improved urban air quality. This study, on the importance of adsorbed water in the photocatalytic oxidation of NOx, has identified important correlations which differentiate the role that water plays in the oxidation of NO and NO2. This observation is significant and offers insights into controlling nitrate selectivity on TiO2 and the potential for increased effectiveness in environmental photocatalyst applications.

AB - The nitrate selectivity of TiO2 has important consequences for its efficiency as a NOx depollution photocatalyst. Most emphasis is typically given to photocatalyst activity, a measure of the rate at which NOx concentrations are reduced, but a reduction in NOx concentration (mainly NO + NO2) is not necessarily a reduction in atmospheric NO2 concentration because the catalytic process itself generates NO2. With NO2 being considerably more toxic than NO, more emphasis on nitrate selectivity, a measure of the NOx conversion to nitrate, and how to maximise it, should be given in engineering photocatalytic systems for improved urban air quality. This study, on the importance of adsorbed water in the photocatalytic oxidation of NOx, has identified important correlations which differentiate the role that water plays in the oxidation of NO and NO2. This observation is significant and offers insights into controlling nitrate selectivity on TiO2 and the potential for increased effectiveness in environmental photocatalyst applications.

KW - supported TiO2

KW - synthesis conditions

KW - adsorbed water

KW - NOx

KW - nitrate selectivity

U2 - 10.1021/acsami.7b01989

DO - 10.1021/acsami.7b01989

M3 - Article

C2 - 28474882

SN - 1944-8244

VL - 9

SP - 17034

EP - 17041

JO - ACS Applied Materials & Interfaces

JF - ACS Applied Materials & Interfaces

IS - 20

ER -

The Different Roles of Water in Photocatalytic DeNOx Mechanisms on TiO2: A Basis for Engineering Nitrate Selectivity?

Abstract

Bibliographical note

Keywords

UN SDGs

Access to Document

Fingerprint

Cite this