Dr Dion Laboratory

Dr Dion

About Dr. Dionysiou

Dr. Dionysios (“Dion”) Dionysiou is a Professor and the Graduate Studies Director for Environmental Engineering and Sciences. He studied Chemical Engineering at the National Technical University of Athens (N.T.U.A.) in Greece and Tufts University before receiving his Ph.D. in Environmental Engineering from the University of Cincinnati. Dr. Dionysiou’s research has received millions of dollars in funding from organizations that include the National Science Foundation (NSF), the U.S. Environmental Protection Agency (EPA), the US Department of Agriculture (USDA), the US Geological Survey (USGS), the USAID, the Ohio Sea Grant, the National Oceanic and Atmospheric Administration-Cooperative Institute for Coastal and Estuarine Environmental Technology (NOAA/CICEET) and DuPont. In 2016 he was named Guest Professor at Harbin Institute of Technology and Adjunct Visiting Professor at Nanjing University in China. In 2015 he was elected Fellow of the American Chemical Society and named Vising Professor at Dalian University of Technology. In 2014, he received the ARCADIS / AEESP Frontier in Research Award as well as the Research Award and Distinguished Engineering Researcher Award from UC’s College of Engineering and Applied Sciences. He has also received numerous other awards from various other organizations and societies as well as excellence in review awards from various scientific journals. Dr. Dionysiou has over 285 peer-reviewed publications and 90 conference proceedings. He edited/co-edited 5 books and published over 20 book chapters. He has presented over 100 invited plenary, keynote, and lecture presentations as well as numerous conference presentations around the world. He is currently one of the editors of Chemical Engineering Journal (Elsevier), Editor of the Journal of Advanced Oxidation Technologies, and Special Issue Editor for the Journal of Environmental Engineering (ASCE). He is a member of the Editorial Boards of ten other journals and he is serving as a reviewer for many national and international journals. Dr. Dionysiou is equally dedicated to his teaching and advising, graduating over 30 Ph.D. and M.S. students who have in turn won many awards. He has served as mentor of over 55 visiting professors, post-doctoral associates and visiting graduate students. He teaches courses in Water and Wastewater Treatment; Environmental Aspects of Nanotechnology; and Physical-Chemical Processes for Water Quality Control.


Dr. Dionysiou performs research in the fields of (1) Advanced oxidation technologies, (2) physical chemical processes for treatment of surface water, groundwater, industrial wastewater, and other types of polluted water, (3) UV and solar light-based remediation processes, (4) treatment of contaminants of emerging concern, (5) remediation of Harmful Algal Blooms/cyanotoxins, (6) transition metal-based chemical oxidation, (7) environmental nanotechnology, (8) (nano) interfacial phenomena in environmental systems, (9) water sustainability, and (10) water-energy-food nexus.

Recent Publications (Examples)

A)   Journal Publications

1)      Afzal Shah, Suniya Shahzad, Azeema Munir, Mallikarjuna. N. Nadagouda, Gul Shahzada Khan, Dilawar Farhan Shams, Dionysios. D. Dionysiou and Usman Ali Rana, Micelles as Soil and Water Decontamination Agents, Chemical Reviews 116 (10) (2016) 6042-6074.

2)      Yiqing Liu, Xuexiang He, Xiaodi Duan, Yongsheng Fu, Despo Fatta-Kassinos, and Dionysios D. Dionysiou, Significant Role of UV and Carbonate Radical on the Degradation of Oxytetracycline in UV-AOPs: Kinetics and Mechanism, Water Research 95 (2016) 195-204.

3)      Wael H. M. Abdelraheem, Xuexiang He, Zanaty R. Komy, Nabawia M. Ismail, Dionysios D. Dionysiou, Revealing the Mechanism, Pathways and Kinetics of UV254nm/H2O2-based Degradation of Model Active Sunscreen Ingredient PBSA, Chemical Engineering Journal 288 (2016) 824-833.

4)      Rachel Fagan, Declan E. McCormack, Dionysios D. Dionysiou, and Suresh C. Pillai, A Review of Solar and Visible Light Active TiO2 Photocatalysis for Treating Bacteria, Cyanotoxins and Contaminants of Emerging Concern, Materials Science in Semiconductor Processing 42 (2016) 2-14.

5)      Sanaullah Khan, Xuexiang He, Hasan M. Khan, Dominic Boccelli, and Dionysios D. Dionysiou, Efficient Degradation of Lindane in Aqueous Solution by Iron (II) and/or UV Activated Peroxymonosulfate, Journal of Photochemistry and Photobiology A: Chemistry 316 (2016) 37-43.

6)      Xuexiang He, Yen-Ling Liu, Amanda Conklin, Judy Westrick, Linda K. Weavers, Dionysios D. Dionysiou, John J. Lenhart, Paula J. Mouser, David Szlag, and Harold W. Walker, Toxic cyanobacteria and drinking water: Impacts, detection, and treatment, Harmful Algae 54 (2016) 174-193.

7)      Swagata Banerjee, Dionysios D. Dionysiou, and Suresh C. Pillai, Self-cleaning Photocatalytic Materials: Mechanism, Synthesis and Environmental Applications, Applied Catalysis B: Environmental 176-177 (2015) 396-428.

8)      I. Michael-Kordatou, C. Michael, X. Duan, X. He, D. D. Dionysiou, M. A. Mills, and D. Fatta-Kassinos, Dissolved Effluent Organic Matter: Characteristics and Potential Implications in Wastewater Treatment and Reuse Applications, Water Research 77 (2015) 213-248.

9)      Xuexiang He, Armah A. de la Cruz, Anastasia Hiskia, Triantafyllos Kaloudis, Kevin O’Shea and Dionysios D. Dionysiou, Destruction of Microcystins (Cyanotoxins) by UV-254 nm-based Direct Photolysis and Advanced Oxidation Processes (AOPs): Influence of the Variable Amino Acids on the Degradation Kinetics and Reaction Mechanisms, Water Research 74 (2015) 227-238.

10)  Swagata Banerjee, Suresh C. Pillai, Polycarpos Falaras, Kevin E. O'Shea, John A. Byrne, and Dionysios D. Dionysiou, New Insights into Visible Light Photocatalysis, Journal of Physical Chemistry Letters 5 (15) (2014) 2543-2554.

11)  Xuexiang He, Geshan Zhang, Armah A. de la Cruz, Kevin E. O’Shea and Dionysios D. Dionysiou, Revealing the Mechanism of the Degradation of Cyanobacterial Toxin Cylindrospermopsin by Homogeneous UV/H2O2 Process, Environmental Science and Technology 48 (8) (2014) 4495-4504.


1)      Photocatalysis : Applications, Editors: Dionysios D. Dionysiou, Gianluca Li Puma, Jinhua Ye, Jenny Schneider, Detlef Bahnemann, Print ISBN: 978-1-78262-709-8, PDF eISBN: 978-1-78262-710-4, EPUB eISBN: 978-1-78262-798-2, DOI:10.1039/9781782627104, RSC Energy and Environment Series No. 15, The Royal Society of Chemistry, United Kingdom, 2016.

2)      Photocatalysis : Fundamentals and Perspectives, Editors: Jenny Schneider, Detlef Bahnemann, Jinhua Ye, Gianluca Li Puma, Dionysios D. Dionysiou, Print ISBN: 978-1-78262-041-9, PDF eISBN: 978-1-78262-233-8, EPUB eISBN: 978-1-78262-826-2, DOI:10.1039/9781782622338, RSC Energy and Environment Series No. 14, The Royal Society of Chemistry, United Kingdom, 2016.

3)      Advanced Treatment Technologies for Urban Wastewater Reuse, Editors: Despo Fatta-Kassinos, Dionysios D. Dionysiou, and Klaus Kümmerer, The Handbook of Environmental Chemistry 45, Series Editors: Damià Barceló and Andrey G. Kostianoy; ISBN 978-3-319-23885-2, 978-3-319-23886-9 (eBook); DOI 10.1007/978-3-319-23886-9, Springer International Publishing, Switzerland, 2016.

4)      Wastewater Reuse and Current Challenges, Editors: Despo Fatta-Kassinos, Dionysios D. Dionysiou, and Klaus Kümmerer, The Handbook of Environmental Chemistry 44, Series Editors: Damià Barceló and Andrey G. Kostianoy; ISBN 978-3-319-23891-3, 978-3-319-23892-0 (eBook); DOI 10.1007/978-3-319-23892-0, Springer International Publishing, Switzerland, 2016.

5)      Water Challenges and Solutions on a Global Scale, Editors: Satinder Ahuja, Jailson B. de Andrade, Dionysios D. Dionysiou, Kiril D. Hristovski, Bommanna G. Loganathan, ACS Symposium Series, Volume 1206, American Chemical Society; ISBN13: 9780841231061; eISBN: 9780841231054; DOI: 10.1021/bk-2015-1206, American Chemical Society, Washington, DC, 2015.

Read more about Dr. Dionysiou’s lab’s research here: 

Homepage 1

Developing nanotechnology to monitor contaminants

Contaminants of emerging concern, including cyanobacterial toxins, pharmaceuticals, pesticides, and personal care products, have been found in surface water bodies worldwide. These contaminants can be toxic and may cause health problems in humans and animals. In order to monitor and decompose these contaminants, Dr. Dion’s group is developing nanobiosensors with high sensitivity and selectivity to specific cyanobacterial toxins such as microcystin-LR, -LA, -YR, and -RR. In 2013, his group and collaborators developed a carbon nanotube-based electrochemical biosensor that can detect microcystin-LR (MC-LR) below the World Health Organization’s provisional concentration limit of 1 μg/L. Currently, different biosensors are in development to determine other cyanobacterial toxins. The group has also developed nanotechnology using titanium dioxide (TiO2) that is activated by light. The technology can help to decompose cyanotoxins, pesticides, and pharmaceuticals. 


Purifying wastewater with a novel bimetallic particle 

Bimetallic particles, or the fusion of two metals into one, have become popular in the treatment of wastewater and groundwater. Yet current particles, such as zero-valent iron (ZVI), do not perform well in neutral pH conditions and the alternatives are often costly. In this project, visiting professor Dr. Fenglian Fu and colleagues are developing a novel, low-cost bimetallic particle made of a core metal (aluminum) and a second metal (iron). They are using this particle to remove Cr(VI) from wastewater in a wide range of pH conditions. Their tests so far have shown that the Fe/Al bimetal has been effective in treating wastewater in varying pH levels, indicating that this particle could meet the demands for rapid and stable Cr(VI) removal in wastewater treatment.

Humic Acid

Removing humic acids from drinking water

Humic acids (HA) can make drinking water discolored, and give it an undesirable taste and odor when they react with the chlorine in water during the drinking water treatment process. This reaction can also produce potential carcinogens such as trihalomethanes and haloacetic acids. Dr. Dionysiou and his colleagues are attempting to remove HAs from drinking water by using adsorption, which is considered the major cause of pollutant deactivation. The removal of the acids is important to both inhibit their toxic properties and restricting their transport in water systems.

His team is using an adsorbent with a high adsorption capacity that can recover easily, making it more practical than other adsorbents to use in the near future.   In particular, they are developing adsorbents with positively charged groups that can efficiently remove HAs. In a detailed study, the group monitored the interaction of HAs with the positively charged adsorbents using adsorption tests and surface characterization techniques.


Treating contaminants in water using oxidation

The hygiene products we use every day, like shampoo, perfume, and sunscreen, have become one of the biggest contaminants in water today. Because these products are used daily, and also can be resistant to traditional water treatment technology, they carry a huge risk to the health of our bodies and our environment. 

Dr. Dionysiou and his team are exploring new means for removing these contaminants with Advanced Oxidation Processes, or AOPs. AOPs are fast, environmentally friendly, and they produce fewer by-products. Currently, his team is using the UV-254nm/H2O2 AOP to destroy an organic UV filter, one that is widely used, persistent in the environment, and can be disruptive to the endocrine system. During this process, reactive oxygen species initiate the destructive process of a water pollutant using hydrogen abstraction, electron transfer and other mechanisms. His team is also studying the behavior of the contaminants during the treatment process by exploring transformation products and reaction pathways.