Teaching activities

->KZ8021 Materials Chemistry for Environmental Applications, Examiner

I accept interns and project students  at bachelor and master levels. Please contact me by e-mail with an application if you are interested in contributing to our reasearch.

Research

Materials for environment

• Fully biobased membranes/ filters for water purification
• Surface chemistry and interactions, mechanical properties, viscoelastic properties, in situ SAXS
• Atomic force microscopy (understanding properties at nano scale, colloidal probe)

Materials for health

• Biobased materials for medical applications
• Tissue engineering, wound dressing, antifouling and antibacterial materials 

Synthesis and processing methods for sustainable materials

• Nanocellulose and nanochitin isolation and characterization
• Designing of recycling and circularity of materials 
• Data driven design of materials
• High through put processing and synthesis

Earlier fundings 

Ongoing projects

BioLUSH  (BIOMASS VALORIZATION FOR SUSTAINABLE AND HIGH-QUALITY FIBRES) www.biolush.eu  is a  EU Horizon Consortium of 12 partners led by Stockholm University with focus on circular use of plant biomass  leading to decarbonization and reduced eutrophication. The project aims  to retain the value of the EU’s fibrous biomass and promote the growth of the European fibrous bio-economy.

CBE JU contribution: €4,5Euros, Duration: May 2023 – April 2027

Feedstock: hemp, forest residues and other green underexplored biomass feedstocks (nettle and seagrasses)

Main products: edible packaging, antibacterial textiles, and impact-resistant car interior products

Circular and Sustainable Materials Synthesis, Processing, Applications and Hazard Assessment Laboratory (CircuLab@WISE)

2024- 2033, 40 MSEK, PIs: Aji Mathew and Belen Martin-Matute

CircuLab@WISE is a platform to experimentally develop and validate safe synthesis, processing and applications of circular and sustainable soft matter materials in a fast and efficient manner. Process and synthesis automation towards specific applications, online and in line monitoring and characterization, and artificial intelligence (AI)-supported analysis are the key pillars of CircuLab@WISE

Mistra Safechem 2020-2028

Nanocellulose  based approach for textile recycling,  toxicity screening and lufecycle analysis. https://www.mistrasafechem.se

Flag ERANET , 2D paper 2024-2027

 Flexible nanocellulose based sunstrated with 2D materials (hBN, MoS2, GO..) for directional thermal condutivity

Swedish Research Council 2022-2025

In situ microscopy, X-ray scattering, and computational modeling for unraveling the synthesis and performance of nanocellulose based membranes in an aqueous medium 

Mistra, Smart Materials, TERRACLEAN, 2017-2025

Biobased membarnes and hybrids for water treatment and antifouling surfaces

https://mistra.org/program/mistra-terraclean/

3D printing of biobased filters functionalised with nanocellulose for water purification 

Wallenberg Wood Science Centre Funding, Functional Materials Research at Stockholm University, 2019-2022 (www.wwsc.se)

The overall project aims to develop new routes to process and produce filters by melt-based 3D printing. The active part in the filters will be based on nanocomposites having nanocellulose as a component, to elucidate how the porosity and surface chemistry can be tailored to provide high water flux, high separation efficiency, and long-term stability in wet environment. 

Understanding nanocellulose hybrid membranes by means of advanced atomic force microscopy (AFM), Raman/NMR spectroscopy, X-ray scattering and computational chemistry methodologies

Swedish Research Council (2018-2021)

The project develops experimental procedures to probe biobased hybrids in liquid medium/ wet conditions using atomic force microscopy and spectroscopy and in situ X-ray scattering, combined with computational chemistry is envisioned in the project to evaluate and predict the self-assembling between nanocellulose and other nanoparticles and understand how the self-assembled morphologies drive the pore structure formation and adsorption in biobased membarnes and filters used for water purification.

Project Co-ordinator: FP7-NMP-2011-SMALL-5, Proposal reference number: 280519-2 2011, Budget: 4M €uros, Co-ordinator, 2012-2016

Principal Investigator:

• Wallenberg Wood Science Centre Funding, Functional Materials Research at Stockholm University, 2015-2019
• Stockholm University Faculty support, 2015- 2019 
• VR 2013, 2014-2017.; Swedish research links
• International collaborative research grants, South Africa, 2009-2011
• Swedish research links, International collaborative research grants, India; 2009-2011
• Nanomembran för rening av gaser och vätskor, Innovationsbron, (2009) 
• Biobased scaffolds, membranes and hydrogels for imporved wound healing and bone regeneration (Bioheal) 
• Swedish Research Links, International collaboration: 2017-2020

Partner: CEREAL (ERANET-SUSFOOD, 2014- 2017; n-POSSCOG, no: 2011-02071
 MNT-ERA.NET 

Transnational Call 2011; H2020, NanoTextsurf, 2017-2020. www.nanotextsurf.eu

A selection from Stockholm University publication database

• Unlocking the potential of post-consumer garments as a source of nanocellulose

  2024. Maria-Ximena Ruiz-Caldas, Varvara Apostolopoulou Kalkavoura, Aji P. Mathew. Cell Reports Physical Science 5 (2)

  Article

  Discarded garments contribute to an environmental crisis worldwide, prompting the development of new strategies for recycling and upcycling. In this work, we present the extraction of nanocellulose from textiles as an underexplored route for upcycling textile garments made of cotton. We summarize the current state of textile waste management worldwide, discuss strategies for extracting nanocellulose from cotton -based textiles, and outline the associated challenges and outlooks in this field. We further aim to highlight the opportunities and advantages of using cotton as a nanocellulose source and stimulate further research in this area.

  Read more about Unlocking the potential of post-consumer garments as a source of nanocellulose

• Lignin-first biorefining of Nordic poplar to produce cellulose fibers could displace cotton production on agricultural lands

  2022. Anneli Adler (et al.). Joule 6 (8), 1845-1858

  Article

  Here, we show that lignin-first biorefining of poplar can enable the production of dissolving cellulose pulp that can produce regenerated cellulose, which could substitute cotton. These results in turn indicate that agricultural land dedicated to cotton could be reclaimed for food production by extending poplar plantations to produce textile fibers. Based on climate-adapted poplar clones capable of growth on marginal lands in the Nordic region, we estimate an environmentally sustainable annual biomass production of ∼11 tonnes/ha. At scale, lignin-first biorefining of this poplar could annually generate 2.4 tonnes/ha of dissolving pulp for textiles and 1.1 m³ biofuels. Life cycle assessment indicates that, relative to cotton production, this approach could substantially reduce water consumption and identifies certain areas for further improvement. Overall, this work highlights a new value chain to reduce the environmental footprint of textiles, chemicals, and biofuels while enabling land reclamation and water savings from cotton back to food production.

  Read more about Lignin-first biorefining of Nordic poplar to produce cellulose fibers could displace cotton production on agricultural lands

• 3D printed polylactic acid (PLA) filters reinforced with polysaccharide nanofibers for metal ions capture and microplastics separation from water

  2023. Natalia Fijoł (et al.). Chemical Engineering Journal 457

  Article

  The need for multifunctional, robust, reusable, and high-flux filters is a constant challenge for sustainable water treatment. In this work, fully biobased and biodegradable water purification filters were developed and processed by the means of three-dimensional (3D) printing, more specifically by fused deposition modelling (FDM).

  The polylactic acid (PLA) – based composites reinforced with homogenously dispersed TEMPO-oxidized cellulose nanofibers (TCNF) or chitin nanofibers (ChNF) were prepared within a four-step process; i. melt blending, ii. thermally induced phase separation (TIPS) pelletization method, iii. freeze drying and iv. single-screw extrusion to 3D printing filaments. The monolithic, biocomposite filters were 3D printed in cylindrical as well as hourglass geometries with varying, multiscale pore architectures. The filters were designed to control the contact time between filter’s active surfaces and contaminants, tailoring their permeance.

  All printed filters exhibited high print quality and high water throughput as well as enhanced mechanical properties, compared to pristine PLA filters. The improved toughness values of the biocomposite filters clearly indicate the reinforcing effect of the homogenously dispersed nanofibers (NFs). The homogenous dispersion is attributed to the TIPS method. The NFs effect is also reflected in the adsorption capacity of the filters towards copper ions, which was shown to be as high as 234 and 208 mg/gNF for TCNF and ChNF reinforced filters, respectively, compared to just 4 mg/g for the pure PLA filters. Moreover, the biocomposite-based filters showed higher potential for removal of microplastics from laundry effluent water when compared to pure PLA filters with maximum separation efficiency of 54 % and 35 % for TCNF/PLA and ChNF/PLA filters, respectively compared to 26 % for pure PLA filters, all that while maintaining their high permeance.

  The combination of environmentally friendly materials with a cost and time-effective technology such as FDM allows the development of customized water filtration systems, which can be easily adapted in the areas most affected by the inaccessibility of clean water.

  Read more about 3D printed polylactic acid (PLA) filters reinforced with polysaccharide nanofibers for metal ions capture and microplastics separation from water

• Understanding the effect of different nanocelluloses on the proliferation and biomechanical properties of E. coli

  2024. Andrea Aguilar-Sánchez (et al.). Cell Reports Physical Science 5 (10)

  Article

  Nanocellulose with specific surface chemistry exhibits divergent effects on bacterial growth. Here, we report the interaction between different nanocelluloses and Escherichia coli (E. coli). When E. coli is exposed to lignin-containing cellulose nanocrystals (L-CNCs) and TEMPO-oxidized cellulose nanofibers (T-CNFs), the growth rate is reduced, but not the viability of bacterial cells in liquid media, with L-CNCs having the most prominent effect. In situ, PeakForce quantitative nanomechanical mapping (PFQNM) revealed that the surface roughness and stiffness of E. coli were affected when in direct contact with the nanocellulose during incubation, except for the cells attached to CNCs, which promote strong adhesion and even the embedding of E. coli. Thus, nanocelluloses with certain surface chemistries, such as T-CNFs and L-CNCs, could be used as complements or alternatives to antimicrobial drugs for controlling and limiting bacterial growth in liquid media and further biofilm formation on surfaces.

  Read more about Understanding the effect of different nanocelluloses on the proliferation and biomechanical properties of E. coli

• In Situ Functionalisation and Upcycling of Post-Consumer Textile Blends into 3D Printable Nanocomposite Filaments

  2024. Varvara Apostolopoulou Kalkavoura (et al.). Advanced Sustainable Systems 8 (9)

  Article

  The linear lifecycle of the textile industry contributes to the enormous waste generation of post-consumer garments. Recycling or repurposing of post-consumer garments typically requires separation of the individual components. This study describes a novel and facile chemo-thermo-mechanical method for producing extrudable pellets, involving one-pot, 2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation of post-consumer polycotton textiles, followed by mild mechanical treatment, all without isolating the constituents of the polycotton blend. The oxidized blend with high cellulose and carboxylate content of 1221 ± 82 mmol COO− per kg of cotton, is pelletised into a masterbatch and further in situ extruded into nanocomposite filaments for 3D printing. The carboxyl groups introduced on the polycotton-based filters enable cotton fibrillation into nanoscaled fibers during mechanical treatment and extrusion resulting to a variety of functional and high surface-finish quality models, including filters and fashion accessories. The electrostatic interactions with positively charged species, such as methylene blue (MB), facilitate their adsorption from water while exhibiting promising adsorption capacities. The adsorption of MB follows the Freundlich model and depends on the printed porosity of the filter. A “trash to treasure” concept for textile waste is further corroborated through the use of the developed 3D printing filament into commodity products.

  Read more about In Situ Functionalisation and Upcycling of Post-Consumer Textile Blends into 3D Printable Nanocomposite Filaments

Show all publications by Aji Mathew at Stockholm University