Progress 09/16/16 to 09/30/18
Outputs
Target Audience:Scientific community in renewable materials, nanotechnology, water remediation, and broader audience including high school students and advertisements in numerous media (e.g. https://nifa.usda.gov/blog/smart-paper-can-conduct-electricity-detect-water). Changes/Problems:We intended to employ the wood filters for the removal of pesticides from water. Given the scarcity of pesticide adsorption studies, we used dyes instead to better assess the filter properties and compared them with other materials reported in the literature. Future research will explore the treatment of hydrological samples contaminated with pesticides. What opportunities for training and professional development has the project provided?Both Noah Ferguson and Amy Clingman received training in the synthesis and characterization of carbon-based nanomaterials. Sheila Goodman was the graduate student conducting the research related to this project, and the results described above were components of her MS thesis in Bioresource Engineering, which she successfully defended in the Spring quarter of 2018. How have the results been disseminated to communities of interest?The products resulting from this research include four peer-reviewed articles in high impact journals and two conference proceedings. The project team members were also deeply involved in communicating with broader audiences about the outcomes of this research and established a partnership with the UW Communication team to advertise some of the results in various media, including local and international blogs, newspapers, radio and TV. Based on the results of this project, Dr. Dichiara and Ms. Goodman also prepared demos of wood filters and paper sensors for university-wide outreach activities, such as the UW's Engineering Discovery Day, Paws-on-Science, and Earth Day events. Furthermore, together with science teachers at the French American School of Puget Sound in Mercer Island, Dr. Dichiara developed educational activities to disseminate the outcome of this research and organize laboratory visits for high-school students. Noteworthy, all activities offered within this framework were given in French by Dr. Dichiara. While processing scientific content in a different language than English required a significant energetic investment, it provided other ways of understanding the world and communicating ideas, promoting inventiveness and creativity. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
The goal of our project consists of developing sustainable carbon-based nanomaterials for water sensing and treatment of aqueous solutions. In the previous year, we synthesized graphene nanoplatelets from recycled wood pulp based on a modified Hummers method. As-produced graphene was mixed with alkali lignin or/and cellulose nanofibrils to generate concentrated dispersion of individualized nanomaterials in water using an innovative double acoustic irradiation system (Goodman SM, Ferguson N, Dichiara AB. Lignin-assisted double acoustic irradiation for concentrated aqueous dispersions of carbon nanotubes. RSC Advances. 2017, 7(9):5488-96). This year, the nanomaterial suspensions were employed to produce (i) paper-based sensors for humidity and liquid water detection and (ii) filters for the removal of dyes from water. The materials produced in this research also served for a dye discoloration study (publication 2). The paper-based sensors were prepared by mixing the nanomaterial suspensions with wood pulp. Paper handsheets were obtained by the successive filtration, pressing and drying of the mixture. With the incorporation of carbon nanomaterials forming a percolated network constituting electric paths in the wood pulp, the resulting papers exhibited electrical conductivity and high sensitivity to humidity and liquid water. Drastic changes in electrical resistance were observed when the papers were immersed in aqueous media, and a reproducible and steady response was obtained for multiple immersion/drying cycles. These unique water sensing characteristics were attributed to the peculiar swelling behavior of cellulose in the presence of water. As detailed in publication 3, when water enters or leaves the amorphous region of cellulose, the cellulose chains either move apart or draw closer together, hence altering electron transport by varying the distance between neighbored carbon nanomaterials above or below the tunneling distance, hence changing the electrical resistance of the bulk material. The inner porosity of basswood was decorated with graphene using a vacuum impregnation method. The properties of the wood filters to adsorb and desorb methylene blue in a dynamic system were examined based on a central composite design. Results showed that graphene was well-dispersed and immobilized on the wood vessel sidewalls. The numerical Yan model provided a good fit to the experimental breakthrough curves, and high uptake capacities up to 46 mg/g were obtained even at relatively low feed concentration. Spent filters were recovered by solvent exchange and reused for five sorption cycles with regeneration efficiency >80%. These results were summarized in publications 1 & 4 and have important implications for the safe and efficient utilization of nanosorbents in environmental remediation and separation applications.
Publications
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Progress 10/01/17 to 09/30/18
Outputs
Target Audience:Scientific community in renewable materials, nanotechnology, water remediation, and broader audience including high school students and advertisements in numerous media (e.g. https://nifa.usda.gov/blog/smart-paper-can-conduct-electricity-detect-water). Changes/Problems:We intended to employ the wood filters for the removal of pesticides from water. Given the scarcity of pesticide adsorption studies, we used dyes instead to better assess the filter properties and compared them with other materials reported in the literature. Future research will explore the treatment of hydrological samples contaminated with pesticides. What opportunities for training and professional development has the project provided?Amy Clingman received training in the synthesis and characterization of carbon-based nanomaterials. Sheila Goodman was the graduate student conducting the research related to this project, and the results described above were components of her MS thesis in Bioresource Engineering, which she successfully defended in the Spring quarter of 2018. How have the results been disseminated to communities of interest?The project team members were deeply involved in communicating with broader audiences about the outcomes of this research and established a partnership with the UW Communication team to advertise some of the results in various media, including local and international blogs, newspapers, radio and TV. Based on the results of this project, Dr. Dichiara and Ms. Goodman also prepared demos of wood filters and paper sensors for university-wide outreach activities, such as the UW's Engineering Discovery Day, Paws-on-Science, and Earth Day events. Furthermore, together with science teachers at the French American School of Puget Sound in Mercer Island, Dr. Dichiara developed educational activities to disseminate the outcome of this research and organize laboratory visits for high-school students. Noteworthy, all activities offered within this framework were given in French by Dr. Dichiara. While processing scientific content in a different language than English required a significant energetic investment, it provided other ways of understanding the world and communicating ideas, promoting inventiveness and creativity. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
The goal of our project consists of developing sustainable carbon-based nanomaterials for water sensing and treatment of aqueous solutions. In the previous year, we synthesized graphene nanoplatelets from recycled wood pulp based on a modified Hummers method. As-produced graphene was mixed with alkali lignin or/and cellulose nanofibrils to generate concentrated dispersion of individualized nanomaterials in water using an innovative double acoustic irradiation system (Goodman SM, Ferguson N, Dichiara AB. Lignin-assisted double acoustic irradiation for concentrated aqueous dispersions of carbon nanotubes. RSC Advances. 2017, 7(9):5488-96). This year, the nanomaterial suspensions were employed to produce (i) paper-based sensors for humidity and liquid water detection and (ii) filters for the removal of dyes from water. The materials produced in this research also served for a dye discoloration study (publication 2). The paper-based sensors were prepared by mixing the nanomaterial suspensions with wood pulp. Paper handsheets were obtained by the successive filtration, pressing and drying of the mixture. With the incorporation of carbon nanomaterials forming a percolated network constituting electric paths in the wood pulp, the resulting papers exhibited electrical conductivity and high sensitivity to humidity and liquid water. Drastic changes in electrical resistance were observed when the papers were immersed in aqueous media, and a reproducible and steady response was obtained for multiple immersion/drying cycles. These unique water sensing characteristics were attributed to the peculiar swelling behavior of cellulose in the presence of water. As detailed in publication 3, when water enters or leaves the amorphous region of cellulose, the cellulose chains either move apart or draw closer together, hence altering electron transport by varying the distance between neighbored carbon nanomaterials above or below the tunneling distance, hence changing the electrical resistance of the bulk material. The inner porosity of basswood was decorated with graphene using a vacuum impregnation method. The properties of the wood filters to adsorb and desorb methylene blue in a dynamic system were examined based on a central composite design. Results showed that graphene was well-dispersed and immobilized on the wood vessel sidewalls. The numerical Yan model provided a good fit to the experimental breakthrough curves, and high uptake capacities up to 46 mg/g were obtained even at relatively low feed concentration. Spent filters were recovered by solvent exchange and reused for five sorption cycles with regeneration efficiency >80%. These results were summarized in publications 1 & 4 and have important implications for the safe and efficient utilization of nanosorbents in environmental remediation and separation applications.
Publications
- Type:
Journal Articles
Status:
Submitted
Year Published:
2018
Citation:
1. Goodman, S.M.; Bura, R.; Dichiara, A.B.; Facile Impregnation of Graphene into Porous Wood Filters for the Dynamic Removal and Recovery of Dyes from Aqueous Solutions, ACS Applied Nano Materials, 1 (10), 5682-5690, 2018.
- Type:
Journal Articles
Status:
Submitted
Year Published:
2018
Citation:
2. Gu, J.; Hu, C.; Zhang, W.; Dichiara, A.B.; Reagentless preparation of shape memory cellulose nanofibril aerogels decorated with Pd nanoparticles and their application in dye discoloration, Applied Catalysis B: Environmental, 237, 482-490, 2018.
- Type:
Journal Articles
Status:
Other
Year Published:
2017
Citation:
3. Dichiara, A.B.; Song, A.; Goodman, S.M.; He, D.; Bai, J.; Smart papers comprising carbon nanotubes and cellulose microfibers for multifunctional sensing applications, Journal of Materials Chemistry A, 5 (38), 20161-20169, 2017. (invited back cover)
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2018
Citation:
4. Goodman, S.M.; Dichiara, A.B.; Innovative chemical & material approaches for sustainable water purification, ACS National Meeting, New Orleans, LA, 03/21/2018.
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Progress 10/01/16 to 09/30/17
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Sheila Goodman was trained in the use of nitrogen physisorption analyzer, UV-vis spectrophotometer, ultrasonic probe disruptor, and optical and electron microscopes. The project also provided an opportunity for Sheila to learn design of experiment methods and practice statistical analysis. In addition, Noah Ferguson was trained in the purification and characterization of carbon nanomaterials. How have the results been disseminated to communities of interest?Contacts have been established with the French American School of Puget Sound located in Mercer Island, WA, to develop upcoming outreach activities for K-12 through K-16 students. What do you plan to do during the next reporting period to accomplish the goals?For the next period, we will prepare sustainable carbon based adsorbent and examine their adsorption properties in aqueous solutions contaminated with organic dyes and pesticides. The removal of organic compounds from water will be conducted in batch and fixed bed adsorption experiments. We will also investigate the influence of environmental factors, such as solution pH, adsorbate concentration and flow rate, on the adsorption properties. Additionally, we will further test the cellulose composites reinforced with high content of carbon nanomaterials for multifunctional sensing applications.
Impacts
What was accomplished under these goals?
The goal of our project is to design sustainable carbon based adsorbents for the removal of organic pollutants, such as dyes and pesticides, from aqueous environments. For that purpose, we have selected carbon nanotubes and graphene as materials of interest for adsorption applications. These nanomaterials exhibit high specific surface area, open pore structure, hydrophobicity, and large delocalized π electrons, which make them very compelling for the uptake of organic compounds. Their high thermochemical stability may provide unique opportunities for the regeneration of spent adsorbents. Furthermore, research is under way to synthesize carbon nanotubes and graphene from renewable sources, using biomass derivatives as feedstock. One of the main challenge associated with the implementation of carbon nanomaterials in practical systems consists of their tendency to readily form aggregates in water by packing of individual nanotubes and graphene, which significantly reduces the number of sites available for adsorption, hence hindering the separation performance. Therefore, it is critical to prevent carbon nanomaterials from aggregating to design adsorbents with superior properties. To this aim, petroleum based surfactants are commonly utilized. In the first phase of this project, we propose to use lignin as a renewable alternative to disperse carbon nanomaterials in aqueous solution. Our hypothesis is based on the molecular structure of lignin, which consists of a three dimensional, highly cross-linked, amphiphilic macromolecule comprising multiple aromatic groups, offering the possibility for π-π interactions with graphitic structures. The first months were devoted to this task and heavily focused on the training of the graduate student Sheila Goodman. After starting with an extensive literature review, Sheila received training on how to operate the different laboratory instruments including nitrogen physisorption analyzer, UV-vis spectrophotometer, ultrasonic probe disruptor, and optical and electron microscopes. She successfully carried out various experiments and verified that her results were consistent with the relevant literature in this field. Using UV-vis absorption spectroscopy and electron microscopy, we demonstrated that alkali lignin presents comparable capability at dispersing carbon nanomaterials than traditional surfactants. More interestingly, we developed a double acoustic irradiation system, which showed great synergy with lignin by increasing its degree of polymerization for more efficient steric stabilization of carbon nanomaterials. With this innovative system, we achieved high concentration aqueous solutions of individualized carbon nanomaterials that remained stable for months at unprecedentedly short processing time and with low amounts of dispersant. This major accomplishment has been published in a peer-review journal and will allow us to prepare superior adsorbents for water remediation in the next phase of this project. Furthermore, these results likely will have great impact in the materials science and composite community, because carbon nanomaterials are typically difficult to process above 4 wt% in polymers and often require toxic organic solvents. Using our lignin-assisted double acoustic irradiation system, we were able to achieve up to 10 wt% loading of carbon nanotubes in cellulose based composites without obvious aggregation, which is remarkable, especially for such a hydrophobic material in a water-based process. The other advantage of our method is that lignin can be conveniently removed from the as-produced composites by simple thermal annealing at 300 °C, hence improving the electrical conductivity of the material
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Our results about employing lignin as a renewable surfactant have been published in the peer-reviewed journal RSC Advances (impact factor: 3.108): Goodman SM, Ferguson N, Dichiara AB. Lignin-assisted double acoustic irradiation for concentrated aqueous dispersions of carbon nanotubes. RSC Advances. 2017, 7(9):5488-96. doi: 10.1039/c6ra25986c.
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Progress 09/16/16 to 09/30/16
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The student has completed all safety trainings required to work in the laboratory, including fire extinguisher, electrical safety, fume hood, basic chemical management, and compressed gas. She has also started the literature review about the conversion of lignocellulosic biomass into carbon based materials by catalytic carbonization and hydrothermal treatment. In addition, she has started taking classes of the MS program in Bioresource Science and Engineering. How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?During the next period, the student will perform the following activities: 1) characterization of the biomass by elemental analysis, UV-vis and FTIR sepctroscopy; 2) Conversion experiments in a hydrothermal and carbonization reactors and physico-chemical characterization of the carbon products; 3) Removal of selected pesticides by adsorption on the as-produced carbon based materials, which will be conducted with the best-performing products in terms of porosity, graphitic content, and presence of oxygen functional groups, as established from step 2.
Impacts
What was accomplished under these goals?
During the two weeks period covered by this report, the student has started graduate studies and activities in the project by meeting with the project advisor (Anthony Dichiara) to detail the plans for the work, which will be reported in future reports.
Publications
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