Project

Back to overview

Small band-gap nanostructured perovskite materials for photovoltaic and photocatalytic hydrogen generation applications

English title Small band-gap nanostructured perovskite materials for photovoltaic and photocatalytic hydrogen generation applications
Applicant Lippert Thomas
Number 142176
Funding scheme Romanian-Swiss Research Programme (RSRP)
Research institution Paul Scherrer Institut
Institution of higher education Paul Scherrer Institute - PSI
Main discipline Material Sciences
Start/End 01.01.2013 - 30.04.2016
Approved amount 327'687.00
Show all

All Disciplines (4)

Discipline
Material Sciences
Other disciplines of Physics
Condensed Matter Physics
Inorganic Chemistry

Keywords (9)

thin films; eco-friendly materials; ferroelectric films; thin film photocatalysis; energy harvesting; band gap engineering; photovoltaic films; oxynitride films; laser nanostructuring

Lay Summary (English)

Lead
Lay summary

Short Summary

The political and socio-economical demand to provide more sustainable energy for today’s society is calling for materials and devices with improved or added functionalities to satisfy these requirements. Semiconducting oxides like perovskite-based materials have the potential to combine photovoltaics and photocatalysis in one bifunctional system where the micro and nanostructure is an important issue for the effectiveness of the energy output.

Background

The development of multifunctional materials is attractive: it widens the range for potential applications, it is reducing production costs, and could provide additional benefits for miniaturization. Perovskites are known multifunctional materials where small changes in the crystalline structure or composition can lead to very different physical properties such as magnetism, ferro- or piezoelectricity. Sometimes these properties are found to co-exist even in the same phase. For renewable energy applications such as photovoltaic or light-induced water splitting to produce hydrogen, semiconducting perovskites are appealing because some compositions e.g. BiFeO3, show photocatalytic properties exceeding industrial standard materials. Often, the maximum for the light induced properties is in the UV wavelength range. By carefully adjusting the anionic composition of selected oxides e.g. partially replacing oxygen for nitrogen during thin film growth, a band-gap engineering can be achieved which will enable to shift the efficiency maximum into the visible range. This targeted anion-exchange will also affect expected photovoltaic properties.

Aim

The aim is to explore the potential of combined photovoltaic and photocatalytic properties of perovskite-based materials with semiconducting properties. They will be grown as thin films which will serve as model systems to understand the mechanisms combing the different functionalities. In addition, different material compositions can be prepared more easily as thin film by controlling the anion and cation composition during the deposition which enables to prepare material compositions with designed photovoltaic and/or photocatalytic properties.

Significance

The potential of perovskite-based materials which exhibit a small band gap with combined photovoltaic and photocatalytic properties is largely unknown. Therefore the search, preparation and characterization of suitable oxide materials is an important task. These oxide may also help to overcome some legally imposed restrictions (restricted use of materials containing elements with high toxicity), as well as to accommodate the social and economical aspects of sustainable energy production.

Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants

Employees

Name Institute

Publications

Publication
LaTiO x N y Thin Film Model Systems for Photocatalytic Water Splitting: Physicochemical Evolution of the Solid-Liquid Interface and the Role of the Crystallographic Orientation
Pichler Markus, Si Wenping, Haydous Fatima, Téllez Helena, Druce John, Fabbri Emiliana, Kazzi Mario El, Döbeli Max, Ninova Silviya, Aschauer Ulrich, Wokaun Alexander, Pergolesi Daniele, Lippert Thomas (2017), LaTiO x N y Thin Film Model Systems for Photocatalytic Water Splitting: Physicochemical Evolution of the Solid-Liquid Interface and the Role of the Crystallographic Orientation, in Advanced Functional Materials, 27(20), 1605690-1605690.
Joining Chemical Pressure and Epitaxial Strain to Yield Y-doped BiFeO3 Thin Films with High Dielectric Response
Nicu D. Scarisoreanu, Floriana Craciun, Ruxandra Birjega, Valentin Ion, Valentin S. Teodorescu, Cornel Ghica, Maria Dinescu (2016), Joining Chemical Pressure and Epitaxial Strain to Yield Y-doped BiFeO3 Thin Films with High Dielectric Response, in Scientific Report, 25535.
TiN-buffered substrates for photoelectrochemical measurements of oxynitride thin films
Markus Pichler, Daniele Pergolesi, Steve Landsmann, Vipin Chawla, Johann Michler, Max Döbeli, Alexander Wokaun, Thomas Lippert (2016), TiN-buffered substrates for photoelectrochemical measurements of oxynitride thin films, in Applied Surface Science, 75.
Tracing the plasma interactions for pulsed reactive crossed-beam laser ablation
Jikun Chen, Dieter Stender, Markus Pichler, Max Döbeli, Daniele Pergolesi, Christof W. Schneider, Alexander Wokaun, Thomas Lippert (2015), Tracing the plasma interactions for pulsed reactive crossed-beam laser ablation, in Journal of Applied Physics, 165306.
Determination of conduction and valence band electronic structure of La2Ti2O7 thin film
Szlachetko Jakub, Pichler Markus, Pergolesi Daniele, Sá Jacinto, Lippert Thomas (2014), Determination of conduction and valence band electronic structure of La2Ti2O7 thin film, in RCS Advances, 4 , 11420-11422.
Multifunctional Oxides Obtained by PLD: Applications as Ferroelectric and Piezoelectric Materials
Nicu D. Scarisoreanu, Maria Dinescu, F. Craciun (2014), Multifunctional Oxides Obtained by PLD: Applications as Ferroelectric and Piezoelectric Materials, in Springer Series in Materials Science (ed.), Springer International Publishing Switzerland, Switzerland, 227-269.

Datasets

Scientific manuscript

Author Pichler, Markus; Szlachetko, Jakub; Castelli, Ivano E.; Marzari, Nicola; Doebeli, Max; Wokaun, Alexander; Pergolesi, Daniele; Lippert , Thomas
Publication date 21.02.2017
Persistent Identifier (PID) 10.1002/cssc.201601632
Repository arXiv.org


Scientific manuscript

Author Pichler, Markus; Si, Wenping; Haydous, Fatima; Tellez, Helena; Druce, John; Fabbri, Emiliana; El Kazzi, Mario; Doebeli, Max; Ninova, Silviya; Aschauer, Ulrich; Wokaun, Alexander; Pergolesi, Daniele; Lippert , Thomas
Publication date 21.02.2017
Persistent Identifier (PID) 10.1002/adfm.201605690
Repository arXiv.org


Collaboration

Group / person Country
Types of collaboration
Solid State Chemistry and Catalysis/Empa Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Research Infrastructure
- Exchange of personnel
Ion Beam Physics/ETH Zurich Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Research Infrastructure
Solid State Chemistry Division/Risoe National Laboratory Denmark (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Faculty of Physics/Unversity of Bucharest Romania (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Research Infrastructure

Associated projects

Number Title Start Funding scheme
152553 Positive or negative? Selecting the charge state of ions during pulsed laser deposition of thin films 01.07.2014 Project funding (Div. I-III)
133793 Pulsed laser deposition chamber for an advanced in situ growth control of oxide thin films and multilayers for materials research 01.12.2010 R'EQUIP
134577 Negative ions: the overlooked species in thin film growth by pulsed laser deposition 01.04.2011 Project funding (Div. I-III)
147190 Influence of Strain and Interfaces on the Properties of Ion Conducting Thin Films for micro-Solid-Oxide-Fuel-Cells 01.05.2013 Project funding (Div. I-III)
172708 Laser interaction with materials for thin film deposition: From fundamentals to functional films 01.08.2017 Project funding (Div. I-III)
126783 Single crystalline films of ion conductors 01.11.2009 Project funding (Div. I-III)

Abstract

The political and socio-economical demand to provide more sustainable energy for today’s society calls for materials and devices with improved or even new functionalities to satisfy these requirements. In addition, present European Union legislation restricts the use of materials containing elements with high toxicity (lead, cadmium, hexavalent chromium, mercury, etc.) for most industrial applications. This is a major problem for all industries, preparing lead based piezoelectric ceramics such as lead-zirconate-titanate, Pb[ZrxTi1-x]O3, which are used in sensors, actuators, and sensitive IR cameras. Another example can be found in thin film photovoltaic based industry where CdTe photovoltaic cells are quite common, but cadmium is one of the above mentioned toxic materials. For this type of photovoltaic cells, a toxic waste problem is expected at two different stages, i.e. during manufacturing and at the module’s end-of-life. Another important aspect to consider is that for the probably most important thin film solar cell of the future, i.e. the CIGS cell (copper-indium-gallium-sulfide/selenide), indium is used, for which resources are limited. In energy related photocatalysis, e.g. water splitting, neither the toxicity nor scarcity of elements is the issue, but the efficiency of the materials. This is due to the fact the commonly used materials (e.g. TiO2), utilizes only a small part (UV) of the solar spectrum. To overcome some of the legally imposed restrictions, as well as to accommodate the social and economical aspects of sustainable energy production, current research on complex oxides with their multitude in functionality may reveal and provide alternatives which could lessen some of the aforementioned boundary conditions. The aim of this proposal is to explore the potential of combined photovoltaic and photocatalytic properties of perovskite-based materials which exhibit a small band gap. Combining different properties has potentially many advantages, e.g. a wider range for potential applications, reducing the production costs, or for miniaturization. Recently a photovoltaic effect in ferroelectric materials, such as BiFeO3 (BFO), has been reported. Ferroelectric materials are characterized by a spontaneous polarization that occurs below the Curie temperature and can be switched by an external electric field. The switchable polarization is sensitive to external stimuli, but now it has been found that the materials respond to light to generate a photocurrent. This promises an impressively high voltage output, which originates from domain walls in the ferroelectric material. BFO exhibits interestingly also photocatalytic properties where the hydrogen generation from water splitting even exceeds the amount generated by an industrial standard material (Degussa Titania P25). This suggests that material research for ferroelectric photovoltaic materials and photocatalytic materials for water splitting can be combined to find and explore bifunctional materials, which is the goal of this proposal. Materials research in this project will be performed by and on thin films which are perfect model system to understand the mechanisms but also because different material compositions can be prepared easily.First known materials, such as BiFeO3 will be deposited as thin films and analyzed in detail for photovoltaic and photocatalytic properties, but we will also try to vary/optimize the domain walls and to analyze the influence of strain in the thin films. As second class of known materials we will deposit perovskite-based oxynitrides, such as LaTiO3-xNx, BaTaO3-xNx, and CaTaO3-xNx, which have photocatalytical activity for visible light. The amount of nitrogen in these compounds will be varied as well as the crystallographic orientation, which requires a detailed analysis of the films. The film properties, such as composition, crystallographic orientation, etc. will be correlated with measurements of photovoltaic and photocatalytic performance. The functionality of a material can also be added or enhanced by nanostructuring and material engineering techniques, which will be both applied to the ABO3 oxides and ABO3-xNx oxynitrides. Finally, additional compounds will be deposited as thin films using cationic doping, e.g. La for BFO, or anionic doping to create oxynitrides, fluoronitrides, and/or fluorooxynitrides, but also materials (YGeO2N or YSiO2N) which have been predicted to show combined photocatalytic and photovoltaic properties. The properties of these materials will be analyzed in detail and results used to evaluate and find strategies for discovering the best bifunctional materials.
-