Dr Roshan Nilantha Kumara Narayana Thotagamuge


Assistant Professor, Centre for Advanced Material and Energy Sciences



Assistant Prof. N T Roshan N Kumara specializes in nanomaterial process, characterizations and applications them for solar cells, gas sensors. He also processes and develops activated carbon for wastewater treatment. Apart from experimental, he does computer simulations for those materials to identify their chemical, electronic and optical properties. He obtained BSc (Physics) degree from University of Ruhuna in 2005. In 2010, he completed his MPhil in Nanotechnology at Wayamba University of Sri Lanka. He obtained the PhD in Applied physics from Universiti Brunei Darussalam in 2015.

He has received professional awards during his academic and research career. These include the presidential research award from the president of Sri Lanka awarded for quality researches (2006), and Graduate Research Scholarship (GSR) from the Universiti Brunei Darussalam (2012) for his doctoral studies. His research interests are in the areas of nanomaterial process, characterizations and fabrication devices such as thin film gas sensor, Dye Sensitized Solar Cells and also wastewater treatment by developing activated carbon.
Apart from research, he has served the duties as a physics lecturer. He was attached to the department of physics, Open university of Sri Lanka and university of Ruhuna Sri Lanka.


Designed and fabricated low cost solar cell by utilizing various dyes and tested and characterized the device performance electrochemically, electrically and optically to improve their efficiencies. Also extracted the natural pigments from various sources and studied their stability, photo-degradation, electrochemical, and photoluminescence properties and identified them.



Sensors, Activated Carbon, Solar cells, Natural Dyes, DSSC, and Nanomaterial process and characterization


Metal oxide nanoparticle for gas sensor

Prevention of unforeseen and sudden accidents within our immediate environment as a result of gaseous pollutants and /or gas cylinder leakage make it necessary for researchers and industrialist across the world to provide effective means for present and future prevention through fabrication of gas sensors. Semiconductor metal oxide gas sensors have been proven to be the most efficient gas sensors exploited so for due to a number of reasons such as simplicity in their fabrication and cost effective.

Applications Invited
PhD in Energy Studies/ Material sciences. Master in Energy Studies/ Material sciences

Gas sensor materials modeling and simulation

Theoretical study always help to understand the more sciences. This modelling and simulation study is to explore the behavior of pristine and different doped metal oxide clusters in the presence of gas molecules. The results may help to understand the mechanism of sensitivity and reactivity improvements in the gas sensors which will be useful for the experimental works. Energy calculations, geometry optimizations, density of states (DOS), and natural bond orbital analyses are some of selected simulation works.

Applications Invited
Master in Energy Studies/ Material sciences. BSc.

Modification of activated carbon for wastewater treatment.

Waste generated as by product from many factories. Zinc, copper, nickel, lead and toxic dye contaminated wastewater has been a major concern due to its extremely hazardous impact on the environment and human health. Adsorption method have been proven to be most effective and low-cost technique for treating the contaminated wastewater. Modified and development of activated carbon with waste biomass as its precursor are considered as an excellent adsorbent for removal of the contaminants due to its cost effective and high adsorption capacity.

Applications Invited
Master in Energy/ Studies/ Material sciences. Bsc.

Scopus Publications


Google Scholar Citations


Google Scholar h-index


Google Scholar i10-index

Scopus Publications


Kumara, N. T. R. N., Lim, A., Lim, C. M., Petra, M. I., & Ekanayake, P. (2017). Recent progress and utilization of natural pigments in dye sensitized solar cells: A review. Renewable and Sustainable Energy Reviews, 78, 301-317.

Kumara, N.T.R.N., Chau, Y.-F. C., Huang, J.-W., Huang, H. J., Lin, C.-T., & Chiang, H.-P. (2016). Plasmonic spectrum on 1D and 2D periodic arrays of rod-shape metal nanoparticle pairs with different core patterns for biosensor and solar cell applications. Journal of Optics, 18(11), 115003.

Chou Chau, Y. F., Lim, C. M., Lee, C., Huang, H. J., Lin, C. T., Kumara, N. T. R. N., . . . Chiang, H. P. (2016). Tailoring surface plasmon resonance and dipole cavity plasmon modes of scattering cross section spectra on the single solid-gold/gold-shell nanorod. Journal of Applied Physics, 120(9). doi:10.1063/1.4962175

Kumara, N. T. R. N., Petrović, M., Peiris, D. S. U., Marie, Y. A., Vijila, C., Petra, M. I., . . . Ekanayake, P. (2015). Efficiency enhancement of Ixora floral dye sensitized solar cell by diminishing the pigments interactions. Solar Energy, 117, 36-45. doi:10.1016/j.solener.2015.04.019

Lim, A., Kumara, N. T. R. N., Tan, A. L., Mirza, A. H., Chandrakanthi, R. L. N., Petra, M. I., . . . Ekanayake, P. (2015). Potential natural sensitizers extracted from the skin of Canarium odontophyllum fruits for dye-sensitized solar cells. Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy, 138, 596-602. doi:10.1016/j.saa.2014.11.102

Kumara, N. T. R. N., Kooh, M. R. R., Lim, A., Petra, M. I., Voo, N. Y., Lim, C. M., & Ekanayake, P. (2013). DFT/TDDFT and experimental studies of natural pigments extracted from black tea waste for DSSC application. International Journal of Photoenergy, 2013. doi:10.1155/2013/109843

N.T.R.N. Kumara, N. Hamdan, M. I. Petra, K. U. Tennakoon, P. Ekanayake, “Equilibrium Isotherm Studies of Adsorption of Pigments Extracted from Kuduk-kuduk (Melastomamalabathricum L.) Pulp onto TiO2 Nanoparticles” Journal of Chemistry, (2014) vol. 2014, Article ID 468975, 6 pages. DOI: 10.1155/2014/468975


Kumara, N. T. R. N., Lim, A., Lim, C. M., Petra, M. I., & Ekanayake, P. (2017). Recent progress and utilization of natural pigments in dye sensitized solar cells: A review. Renewable and Sustainable Energy Reviews, 78, 301-317.

Samarasekara, P., Kumara, N. T. R. N., & Yapa, N. U. S. (2006). Sputtered copper oxide (CuO) thin films for gas sensor devices. Journal of Physics Condensed Matter, 18(8), 2417-2420. doi:10.1088/0953-8984/18/8/007

Samarasekara, P., Yapa, N. U. S., Kumara, N. T. R. N., & Perera, M. V. K. (2007). CO2 gas sensitivity of sputtered zinc oxide thin films. Bulletin of Materials Science, 30(2), 113-116. doi:10.1007/s12034-007-0020-y

Kumara, N. T. R. N., Ekanayake, P., Lim, A., Liew, L. Y. C., Iskandar, M., Ming, L. C., & Senadeera, G. K. R. (2013). Layered co-sensitization for enhancement of conversion efficiency of natural dye sensitized solar cells. Journal of Alloys and Compounds, 581, 186-191. doi:10.1016/j.jallcom.2013.07.039

Ekanayake, P., Kooh, M. R. R., Kumara, N. T. R. N., Lim, A., Petra, M. I., Yoong, V. N., & Ming, L. C. (2013). Combined experimental and DFT-TDDFT study of photo-active constituents of Canarium odontophyllum for DSSC application. Chemical Physics Letters, 585, 121-127. doi:10.1016/j.cplett.2013.08.094


Low operating temperature thin film gas sensor
01/12/2016 - 30/11/2019

Low temperature gas sensor and computer simulation for optimization of the material properties