Teaching activities

->KZ8021 Materials Chemistry for Environmental Applications, Examiner

I accept interns and project students on both first and second level. 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 
• Processing and characterisation of bionanocomposites, hybrids and crosslinked polymers

On-going projects

Catalytic fractionation of forest residues and recycled textiles to generate materials and chemicals) 

Mistra Safechem, 2020-2024 

The research programme Safe and Efficient Chemistry by Design (SafeChem) aims to improve the ability of industry to reduce hazardous chemical exposure to the human population and the environment through implementation of the toolbox system developed within the programme. 

Circularity of materials and extension of the value chain of produced goods is an area of utmost relevance in green and sustainable industries and society. This task will focus on recycling and conversion of cottonbased textiles, and fractionation and conversion of low valued lignocellulosic feedstocks such as tops, roots and branches from forestry into chemicals, nanocellulose and renewable products produced from these materials.

The project will interact with, and contribute to, industries along the value chain including e.g. the textile industry, forest industry, and the biofuel and chemical industry.

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.

Mistra, Smart Materials, TERRACLEAN 2017-2024 

www.mistraterraclean.com

With a vision to address global sustainability challenges, the Mistra TerraClean program will use naturally occurring and commercially important raw materials indigenous to Sweden, such as (nano)cellulose and mesoporous inorganic materials invented and developed in Sweden, to develop smart materials for removal of chemical wastes and pollutants from ambient water and air in the environment and industrial effluents. 

Earlier fundings 

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

• 3D printing of cellulose/leaf-like zeolitic imidazolate frameworks (CelloZIF-L) for adsorption of carbon dioxide (CO₂) and heavy metal ions

  2023. Hani Nasser Abdelhamid, Sahar Sultan, Aji P. Mathew. Dalton Transactions 52 (10), 2988-2998

  Article

  Metal–organic frameworks (MOFs) have advanced several technologies. However, it is difficult to market MOFs without processing them into a commercialized structure, causing an unnecessary delay in the material's use. Herein, three-dimensional (3D) printing of cellulose/leaf-like zeolitic imidazolate frameworks (ZIF-L), denoted as CelloZIF-L, is reported via direct ink writing (DIW, robocasting). Formulating CelloZIF-L into 3D objects can dramatically affect the material's properties and, consequently, its adsorption efficiency. The 3D printing process of CelloZIF-L is simple and can be applied via direct printing into a solution of calcium chloride. The synthesis procedure enables the formation of CelloZIF-L with a ZIF content of 84%. 3D printing enables the integration of macroscopic assembly with microscopic properties, i.e., the formation of the hierarchical structure of CelloZIF-L with different shapes, such as cubes and filaments, with 84% loading of ZIF-L. The materials adsorb carbon dioxide (CO₂) and heavy metals. 3D CelloZIF-L exhibited a CO₂ adsorption capacity of 0.64–1.15 mmol g⁻¹ at 1 bar (0 °C). The materials showed Cu²⁺ adsorption capacities of 389.8 ± 14–554.8 ± 15 mg g⁻¹. They displayed selectivities of 86.8%, 6.7%, 2.4%, 0.93%, 0.61%, and 0.19% toward Fe³⁺, Al³⁺, Co²⁺, Cu²⁺, Na⁺, and Ca²⁺, respectively. The simple 3D printing procedure and the high adsorption efficiencies reveal the promising potential of our materials for industrial applications.

  Read more about 3D printing of cellulose/leaf-like zeolitic imidazolate frameworks (CelloZIF-L) for adsorption of carbon dioxide (CO₂) and heavy metal ions

• CelloZIFPaper: Cellulose-ZIF Hybrid Paper for Heavy Metal Removal and Electrochemical Sensing

  2022. Hani Nasser Abdelhamid (et al.). Chemical Engineering Journal 446

  Article

  The processing of hierarchical porous zeolitic imidazolate frameworks (ZIF-8) into a cellulose paper using sheet former Rapid-Köthen (R.K.) is reported. The procedure is a promising route to overcome a significant bottleneck towards applying metal-organic frameworks (MOFs) in commercial products. ZIF-8 crystals were integrated into cellulose pulp (CP) or TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-oxidized cellulose nanofibrils (TOCNF) following an in-situ or ex-situ process; the materials were denoted as CelloZIFPaper_In Situ and CelloZIFPaper_Ex Situ, respectively. The materials were applied as adsorbents to remove heavy metals from water, with adsorption capacities of 66.2–354.0 mg/g. CelloZIFPaper can also be used as a stand-alone working electrode for the selective sensing of toxic heavy metals, for instance, lead ions (Pb²⁺), using electrochemical-based methods with a limit of detection (LOD) of 8 µM. The electrochemical measurements may advance 'Lab-on-CelloZIFPaper' technologies for label-free detection of heavy metal ions.

  Read more about CelloZIFPaper

• Citrated cellulose nanocrystals from post-consumer cotton textiles

  2023. Maria-Ximena Ruiz-Caldas (et al.). Journal of Materials Chemistry A

  Article

  We propose a new method for the extraction of cellulose nanocrystals (CNCs) from post-consumer cotton textiles through surface functionalization followed by mechanical treatment. Cotton-based textiles were esterified using an 85 wt% solution of citric acid at 100 degrees C, then further fibrillated in a microfluidizer. The final product, citrated cellulose nanocrystals (CitCNCs), was a dispersion of needle-like nanoparticles with high crystallinity. Up to 78 wt% of the cotton fabric was converted to CitCNCs that exhibited higher yields and a higher surface group content than CNCs extracted through H2SO4 hydrolysis, although CitCNCs showed a broader size distribution and decreased thermal stability. Experimental data supported by DFT calculations showed that the carboxyl groups on the CitCNC surface are bonded to cellulose by mono or diester linkages. An early-stage life cycle assessment (LCA) was performed to evaluate the environmental impact of using discarded textiles as a source of cellulose and analyze the environmental performance of the production of CitCNCs. Our work showed a significant reduction in the environmental burden of CNC extraction using post-consumer cotton instead of wood pulp, making clothing a good feedstock. The environmental impact of CitCNC production was mainly dominated by citric acid. As a proof of concept, around 58 wt% of the citric acid was recovered through evaporation and subsequent crystallization, which could reduce climate impact by 40%. With this work, we introduce a catalyst-free route to valorize textiles with the extraction of CitCNCs and how conducting LCA in laboratory-scale processes might guide future development and optimization.

  Read more about Citrated cellulose nanocrystals from post-consumer cotton textiles

• 3D-printable biopolymer-based materials for water treatment: A review

  2022. Natalia Fijoł, Andrea Aguilar-Sanchez, Aji P. Mathew. Chemical Engineering Journal 430

  Article

  The global environmental concerns drive scientists all over the world to develop eco-friendly and sustainable alternatives to techniques and materials commonly used until now for water treatment applications. The relatively novel Additive manufacturing (AM) technology allows to process materials in a custom optimized, cost and time effective manner, while use of biobased materials minimizes the secondary pollution issue. Combining three-dimensional (3D) printing technology and biopolymer-based materials refines the water treatment industry, as it provides tailored water filtration systems easily available in the disadvantaged areas at low environmental impact and cost due to the raw materials' bio-origin and abundance. This review highlights the combination of various 3D printing techniques such as Fused deposition modelling (FDM), Direct ink wetting (DIW) and Stereolitography (SLA) with nature-derived biopolymers and biopolymerbased materials including chitosan, Polylactic acid (PLA), alginate and Cellulose acetate (CA) for their potential application within the water treatment industry with emphasis on oil separation and metal removal. Moreover, the environmental impact of the revised biopolymers is briefly discussed.

  Read more about 3D-printable biopolymer-based materials for water treatment

• In-Situ Growth of Metal Oxide Nanoparticles on Cellulose Nanofibrils for Dye Removal and Antimicrobial Applications

  2020. Luis Valencia (et al.). ACS Applied Nano Materials 3 (7), 7172-7181

  Article

  Nanocellulose is known to act as a platform for the in-situ formation of metal oxide nanoparticles, where the multiple components of the resultant hybrids act synergistically toward specific applications. However, typical mineralization reactions require hydrothermal conditions or addition of further reducing agents. Herein, we demonstrate that carboxylated cellulose nanofibril-based films can spontaneously grow functional metal oxide nanoparticles during the adsorption of heavy metal ions from water, without the need of any further chemicals or temperature. Despite the apparent universality of this behavior with different metal ions, this work focuses on studying the in-situ formation of copper oxide nanoparticles on TOCNF films as well as the resultant hybrid films with improved functionality toward dye removal from water and antimicrobial activity. Using a combination of cutting-edge techniques (e.g., in-situ SAXS and QCMD) to systematically follow the nanoparticle formation on the nanocellulosic films in real time, we suggest a plausible mechanism of assembly. Our results confirm that carboxylated cellulose nanofibril films act as universal substrate for the formation of metal oxide nanoparticles, and thus hybrid nanomaterials, during metal ion adsorption processes. This phenomenon enables the upcycling of nanocellulosic materials through multistage applications, thus increasing its sustainability and efficiency in terms of an optimal use of resources.

  Read more about In-Situ Growth of Metal Oxide Nanoparticles on Cellulose Nanofibrils for Dye Removal and Antimicrobial Applications

Show all publications by Aji Mathew at Stockholm University