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Full title of the project: Multifunctional, high performance cellulose-based substrates for photovoltaics and optoelectronics (Tandem Forest Values Programme – Academy of Finland)

More about the project:

The novelty of SUBSTAINABLE lies in developing multifunctional biomaterial composites that target highly ambitious increases both in efficiency and in durability of photovoltaic devices. By using cellulose nanocrystals, cellulose nanofibrils and holocellulose as matrices for multifunctional substrates, we combine the optical tunability of the cellulose-containing films to maximize the transmittance of visible light and the possibility to dope and covalently modify cellulosics for UV light down conversion and filtration. We target ambitious photocurrent increases (25% compared to a standard glass-based device) and management of the two main degradation pathways for photovoltaics, namely UV light and moisture exposure. We will develop novel structures and insight to overcome lifetime limitations to address these primary remaining barriers to commercialization of these cellulose films.

Besides harnessing major increases in performance, cellulose-based substrates offer an abundance of other key benefits, including the potential to reduce the embedded energy of photovoltaic devices and consequently energy payback time, as well as light-weight devices, flexibility required for roll-to-roll production, and easier disposal compared to standard devices. In the long term, the expected results of our project pave the way for a new high value solar energy product family for the Nordic forestry industry.

Even though the term of the project officially finished, the related research work is still active within the MMD group.​

Project team

Yazan Al Haj, Doctoral Candidate

"My research work focuses on the development of flexible energy storage and conversion devices using bio-based resources. I currently work on the conversion of daily biowaste, animal bones and brewery residues into more valuable materials, such as porous carbon and cellulose nanocrystals. Porous carbon will be used as an electrode material, whereas cellulose nanocrystal will be used as a host matrix for the formation of the hydrogel electrolyte for flexible supercapacitors."

Hamidreza Daghigh Shirazi, Doctoral Candidate

"In my doctoral research, I am focusing on improving the lifetime and efficiency of solar cell substrates by means of organic light management layers. For this purpose, my work currently involves translation of leaf structures into functional hierarchical surfaces. As a result, tunable substrate surface with self-cleaning and icephobic properties can be made by combining, for instance, leaf replication, all-optical patterning of azopolymers, and coating with hydrophobic nanoparticles."

Contact information:

Accountable project leader: Prof. Jaana Vapaavuori (jaana.vapaavuori@aalto.fi)

Project researchers:
Fangxin Zou, Postdoctoral Researcher (fangxin.zou@aalto.fi)
Yazan Al Haj, Doctoral Candidate (yazan.alhaj@aalto.fi)
Hamidreza Daghigh Shirazi, Doctoral Candidate (hamidreza.daghighshirazi@aalto.fi)

Project page on the Research Aalto portal:

The project is being implemented in collaboration with the of Prof. Kati Miettunen from the University of Turku (Finland) and from the RISE Research Institutes of Sweden.