Type II Heterostructures: The Way Towards Improved Photoelectrochemical Activity of Graphitic Carbon Nitride

Type II Heterostructures: The Way Towards Improved Photoelectrochemical Activity of Graphitic Carbon Nitride

Photoelectrochemical (PEC) water splitting is promising approach of solar energy conversion. Graphitic carbon nitride can be given as an example of metal-free and cheap semiconducting material for photoelectrochemical reactions however its activity is very low, probably due to high rate of unfavorab...

Full description

Saved in:
Bibliographic Details
Published in:Journal of inorganic and organometallic polymers and materials Vol. 28; no. 2; pp. 492 - 499
Main Authors: Wojtyła, Szymon, Szmit, Konrad, Baran, Tomasz
Format: Journal Article
Language:English
Published: New York Springer US 01-03-2018
Springer Nature B.V
Subjects:
Carbon
Carbon nitride
Chemistry
Chemistry and Materials Science
Copper
Copper oxides
Current carriers
Heterojunctions
Heterostructures
Inorganic Chemistry
Organic Chemistry
Photoelectric effect
Photoelectric emission
Photovoltaic cells
Polymer Sciences
Solar energy conversion
Water splitting
Inorganic composites
PEC water splitting
g-C
Copper oxides
N
Photocathode
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Photoelectrochemical (PEC) water splitting is promising approach of solar energy conversion. Graphitic carbon nitride can be given as an example of metal-free and cheap semiconducting material for photoelectrochemical reactions however its activity is very low, probably due to high rate of unfavorable charge carriers recombination. Type II heterostructure, graphitic carbon nitride–copper oxide (g-C 3 N 4 and CuO), showed improved photoelectrochemical activity in comparison with neat g-C 3 N 4 . Visible-light irradiated composite generates cathodic photocurrents under middle bias and therefore it can be used as a photocathode for water splitting with hydrogen formation. The band bending existing in type II heterostructures drives the photogenerated electrons and holes to move in opposite directions, resulting in a spatial separation of the photogenerated charge carriers on different sides of heterojunction. Lower recombination rate and higher activity are the overall effects. Moreover, by using copper based underlayer (metallic copper) or overlayer (copper iodide) the PEC activity grows. In particular CuI@g-C 3 N 4 _CuO showed the highest photocurrent density and the “relax time” in dark conditions has an noticeable influence on the further increase in activity.
ISSN:1574-1443
1574-1451
DOI:10.1007/s10904-017-0733-3