ORCID Profile
0000-0001-5478-6887
Current Organisation
The Cyprus Institute
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Energy Generation, Conversion and Storage Engineering | Mechanical Engineering | Heat and Mass Transfer Operations | Nanomaterials | Functional Materials | Nanotechnology | Fluidisation and Fluid Mechanics | Numerical Modelling and Mechanical Characterisation | Non-automotive Combustion and Fuel Engineering (incl. Alternative/Renewable Fuels) | Interdisciplinary Engineering | Ceramics | Nanotechnology not elsewhere classified |
Solar-Thermal Energy | Hydrogen-based Energy Systems (incl. Internal Hydrogen Combustion Engines) | Energy Storage (excl. Hydrogen) | Expanding Knowledge in Engineering | Hydrogen Storage | Expanding Knowledge in Technology
Publisher: OSA
Date: 2018
Publisher: OSA
Date: 2018
Publisher: Elsevier BV
Date: 11-2017
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0RA02353A
Abstract: A representative volume of LCMA coated porous SiC showing a maximum of 23% shrinkage when subject to high-temperature CO 2 conversion redox reactions. This results in significant structural changes including a reduction in specific surface area.
Publisher: Mineralogical Society of America
Date: 11-2018
Publisher: Elsevier BV
Date: 11-2023
Publisher: The Optical Society
Date: 19-05-2016
DOI: 10.1364/OE.24.00A985
Publisher: Elsevier BV
Date: 07-2021
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1RA02234B
Abstract: Cerium doping into the V 2 O 5 lattice forms a reversible V 2 O 3 /VO redox pair after sequential methane partial oxidation and CO 2 /H 2 O splitting reactions and produces syngas (H 2 , CO) with fast rates and high oxygen exchange capacity.
Publisher: AIP Publishing
Date: 04-04-2022
DOI: 10.1063/5.0082365
Abstract: Reforming of methane to produce synthesis gas for the Fischer–Tropsch process provides an alternative to fossil fuels. Silica-encaged ceria–nickel hydroxide catalysts were produced by an in situ synthesis method to obtain ultrafine bimetallic species dispersed evenly within the mesoporous silica matrix. Dry reforming and reduction-oxidation cycling was undertaken with the materials. Catalysts with high content of nickel showed good activity during dry reforming, with conversions rates close to equilibrium in equimolar conditions. Insignificant deactivation of the catalysts was observed over 5 h and 50 h of reaction at 900 °C. Syngas production via reduction–oxidation cycling was shown to be insignificant as compared to continuous catalytic reforming.
Publisher: Elsevier BV
Date: 12-2023
Publisher: Elsevier BV
Date: 03-2020
Publisher: American Chemical Society (ACS)
Date: 07-03-2019
Publisher: American Chemical Society (ACS)
Date: 26-06-2020
Publisher: Elsevier BV
Date: 05-2020
Publisher: Elsevier BV
Date: 07-2023
Publisher: Wiley
Date: 23-04-2021
DOI: 10.1002/AIC.17267
Abstract: The effects of particle size and carbon dioxide concentration on chemical conversion in engineered spherical particles undergoing calcium oxide looping are investigated. Particles are thermochemically cycled in a furnace under different carbon dioxide concentrations. Changes in composition due to chemical reactions are measured using thermogravimetric analysis. Gas composition at the furnace exit is evaluated with mass spectroscopy. A numerical model of thermal transport phenomena developed previously is adapted to match the physical system investigated in the present study. The model is used to elucidate effects of reacting medium characteristics on particle temperature and reaction extent. Experimental and numerical results show that (1) an increase in particle size results in a decrease in carbonation extent, and (2) the carbonation step consists of fast and slow reaction regimes. The reaction rates in the fast and slow carbonation regimes increase with increasing carbon dioxide concentration. The effect of carbon dioxide concentration and the distinction between the fast and slow regimes become more pronounced with increasing particle size.
Publisher: Elsevier BV
Date: 2020
Publisher: Elsevier BV
Date: 09-2021
Publisher: Research Square Platform LLC
Date: 30-11-2020
DOI: 10.21203/RS.3.RS-110731/V1
Abstract: High-efficiency and wavelength-tunable light emitting diode (LED) devices will play an important role in future advanced optoelectronic systems. Traditional semiconductor LED devices typically have a fixed emission wavelength that is determined by the energy of the emission states. Here, we developed a novel high-efficiency and wavelength-tunable monolayer WS 2 LED device, which operates in the hybrid mode of continuous-pulsed injection. This hybrid injection enables highly enhanced emission efficiency ( 20 times) and the effective size of emission area ( 5 times) at room temperature. The emission wavelength of WS 2 monolayer LED device can be tuned over more than 40 nm by driving AC voltages, from exciton emission to trion emission, and further to defect emissions. The quantum efficiency of defect electroluminescence (EL) emission is measured to be more than 24.5 times larger than that from free exciton and trion EL emissions. The separate carrier injection in our LED also demonstrate advantage in allowing to visualize and distinguish defect species in real space. Those defects are assigned to be negatively charged defects. Our results open a new route to develop high-performance and wavelength-tunable LED devices for future advanced optoelectronic applications.
Publisher: Elsevier BV
Date: 05-2021
Publisher: Elsevier BV
Date: 08-2022
Publisher: Elsevier BV
Date: 11-2014
Publisher: American Chemical Society (ACS)
Date: 03-09-2018
Publisher: Elsevier BV
Date: 08-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1SE01615F
Abstract: Algal biomass is an attractive feedstock for carbon-neutral fuel production due to high growth rates and its potential to be farmed in artificial ponds on non-arable land.
Publisher: American Chemical Society (ACS)
Date: 03-09-2018
Publisher: American Chemical Society (ACS)
Date: 05-10-2021
Publisher: Optica Publishing Group
Date: 17-06-2020
DOI: 10.1364/OE.389924
Abstract: We propose a concept of a rotating tower reflector (TR) in a beam-down optical system to alternate concentrated solar irradiation of an array of solar receiver–reactors, realizing multi-step solar thermochemical redox cycles. Optical and radiative characteristics of the proposed system are explored analytically and numerically by Monte-Carlo ray-tracing simulations. We study the effects of the system geometrical and optical parameters on the optical and radiative performance. TR axis is required to be tilted for accommodating the receiver–reactor array, resulting in reduced optical efficiency. We demonstrate that the annual optical efficiency of a baseline system with the receiver–reactor located south of the tower decreases from 46% to 37% for the axis tilt angle of TR increasing from 2° to 20°. The optical analysis conducted in this study provides a general formulation to enable predictions of required gain of thermal-to-chemical efficiency of the receiver–reactor array for obtaining improved overall solar-to-chemical efficiency of the solar thermochemical plant.
Publisher: American Society of Mechanical Engineers
Date: 09-07-2017
DOI: 10.1115/HT2017-5117
Abstract: Radiation absorption by a particle curtain formed in a solar free falling particle receiver is investigated using a Eulerian-Eulerian granular two-phase model to solve the two-dimensional mass and momentum equations (CFD). The radiative transfer equation is subsequently solved by the Monte-Carlo (MC) ray-tracing technique using the CFD results to quantify the radiation intensity through the particle curtain. The CFD and MC results provide reliable opacity predictions and are validated with the experimental results available in literature. The particle curtain was found to absorb the solar radiation efficiently for smaller particles at high flowrates due to higher particle volume fraction and increased radiation extinction. However, at low mass-flowrates the absorption efficiency decreases for small and large particles.
Publisher: Wiley
Date: 24-03-2021
Abstract: Two‐step solar thermochemical water splitting is a promising pathway for renewable fuel production due to its potential for high thermal efficiency via full‐spectrum sunlight utilization. Such a promise critically relies on simultaneous innovation in the redox materials and the reactor systems. Most prior efforts on material design are focused on improving the fuel yield at lower reduction temperatures. However, developing materials with both high fuel output and efficiency remains a key challenge, requiring a rigorous understanding of the effects of material thermodynamic properties. Herein, a generic thermodynamic framework is described to decipher the material effects by studying both the state‐of‐the‐art and hypothetical materials within a counterflow reactor system. A global efficiency map is presented for redox materials, revealing inevitable tradeoffs among competing factors such as thermal losses, sweep gas and oxidizer demand, solid preheating, and reduction enthalpy. The choice of the most efficient material is closely linked to the system conditions. Ceria‐based materials outperform perovskites under most scenarios, and the optimal hypothetical materials tend to favor higher reduction enthalpies and entropies than existing materials. This work offers a valuable material design roadmap to identify solutions toward efficient solar fuel production.
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9TA06471K
Abstract: Developing an efficient redox material is a fundamental and crucial step in sustainable hydrocarbon fuel production via solar energy-driven thermochemical redox cycles.
Publisher: Mineralogical Society of America
Date: 11-2018
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1EE03028K
Abstract: Stony coral morphology inspires ultra-stable sunlight absorber structure with highest reported absorptance for high-temperature solar thermal applications.
Publisher: AIP Publishing
Date: 2019
DOI: 10.1063/1.5117588
Publisher: AIP Publishing
Date: 2019
DOI: 10.1063/1.5117542
Publisher: Elsevier BV
Date: 08-2018
Publisher: Elsevier BV
Date: 03-2023
Publisher: Elsevier BV
Date: 10-2022
Publisher: OSA
Date: 2017
Publisher: Research Square Platform LLC
Date: 21-09-2021
DOI: 10.21203/RS.3.RS-919328/V1
Abstract: Concentrating solar thermal (CST) is an efficient renewable energy technology with low-cost thermal energy storage. CST relies on wide-spectrum solar thermal absorbers that must withstand high temperatures ( 700°C) for many years, but state-of-the-art coatings have poor optical stability. Here, we show that the largely overlooked macro-scale morphology is key to enhancing both optical resilience and light trapping. Inspired by stony-coral morphology, we developed a hierarchical coating with three tuneable length-scale morphologies: nano- (~ 120 nm), micro- (~ 3 µm) and macro-scales ( 50 µm). Our coating exhibits outstanding, stable solar-weighted absorptance of 97.75 ± 0.04% after ageing at 850°C for more than 2,000 hours. The scalability of our coating is demonstrated on a commercial solar thermal receiver, paving the way for more reliable high-performance solar thermal systems.
Publisher: American Chemical Society (ACS)
Date: 20-09-2019
Publisher: Elsevier BV
Date: 04-2018
Publisher: Elsevier BV
Date: 08-2014
Publisher: Elsevier BV
Date: 05-2023
Publisher: Author(s)
Date: 2018
DOI: 10.1063/1.5067125
Publisher: Begell House
Date: 2013
Publisher: Elsevier BV
Date: 05-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6TA02187E
Abstract: The flame-made nanostructured agglomerates achieved ca. 200% higher syngas production rates and the highest redox capacity so far reported for ceria.
Publisher: Author(s)
Date: 2017
DOI: 10.1063/1.4984354
Publisher: Elsevier BV
Date: 04-2022
Publisher: Elsevier BV
Date: 03-2022
Publisher: American Association for the Advancement of Science (AAAS)
Date: 2020
Abstract: The effects of V and Ce concentrations (each varying in the 0–100% range) in vanadia–ceria multiphase systems are investigated for synthesis gas production via thermochemical redox cycles of CO 2 and H 2 O splitting coupled to methane partial oxidation reactions. The oxidation of prepared oxygen carriers is performed by separate and sequential CO 2 and H 2 O splitting reactions. Structural and chemical analyses of the mixed-metal oxides revealed important information about the Ce and V interactions affecting their crystal phases and redox characteristics. Pure CeO 2 and pure V 2 O 5 are found to offer the lowest and highest oxygen exchange capacities and syngas production performance, respectively. The mixed-oxide systems provide a balanced performance: their oxygen exchange capacity is up to 5 times higher than that of pure CeO 2 while decreasing the extent of methane cracking. The addition of 25% V to CeO 2 results in an optimum mixture of CeO 2 and CeVO 4 for enhanced CO 2 and H 2 O splitting. At higher V concentrations, cyclic carbide formation and oxidation result in a syngas yield higher than that for pure CeO 2 .
Publisher: ASME International
Date: 26-06-2018
DOI: 10.1115/1.4040290
Abstract: Radiation absorption is investigated in a particle curtain formed in a solar free-falling particle receiver. An Eulerian–Eulerian granular two-phase model is used to solve the two-dimensional mass and momentum equations by employing computational fluid dynamics (CFD) to find particle distribution in the curtain. The radiative transfer equation (RTE) is subsequently solved by the Monte Carlo (MC) ray-tracing technique to obtain the radiation intensity distribution in the particle curtain. The predicted opacity is validated with the experimental results reported in the literature for 280 and 697 μm sintered bauxite particles. The particle curtain is found to absorb the solar radiation most efficiently at flowrates upper-bounded at approximately 20 kg s−1 m−1. In comparison, 280 μm particles have higher average absorptance than 697 μm particles (due to higher radiation extinction characteristics) at similar particle flowrates. However, as the absorption of solar radiation becomes more efficient, nonuniform radiation absorption across the particle curtain and hydrodynamic instability in the receiver are more probable.
Publisher: ASME International
Date: 08-01-2019
DOI: 10.1115/1.4042228
Abstract: A thermodynamic model of an isothermal ceria-based membrane reactor system is developed for fuel production via solar-driven simultaneous reduction and oxidation reactions. Inert sweep gas is applied on the reduction side of the membrane. The model is based on conservation of mass, species, and energy along with the Gibbs criterion. The maximum thermodynamic solar-to-fuel efficiencies are determined by simultaneous multivariable optimization of operational parameters. The effects of gas heat recovery and reactor flow configurations are investigated. The results show that maximum efficiencies of 1.3% (3.2%) and 0.73% (2.0%) are attainable for water splitting (carbon dioxide splitting) under counter- and parallel-flow configurations, respectively, at an operating temperature of 1900 K and 95% gas heat recovery effectiveness. In addition, insights on potential efficiency improvement for the membrane reactor system are further suggested. The efficiencies reported are found to be much lower than those reported in literature. We demonstrate that the thermodynamic models reported elsewhere can violate the Gibbs criterion and, as a result, lead to unrealistically high efficiencies. The present work offers enhanced understanding of the counter-flow membrane reactor and provides more accurate upper efficiency limits for membrane reactor systems.
Publisher: Elsevier BV
Date: 06-2019
Publisher: Elsevier BV
Date: 09-2022
Publisher: The Optical Society
Date: 19-03-2018
DOI: 10.1364/OE.26.00A360
Publisher: Elsevier BV
Date: 11-2021
Publisher: Optica Publishing Group
Date: 12-2020
DOI: 10.1364/OE.404867
Abstract: A multi-aperture solar central receiver system is optically analyzed for increasing the net power to the receiver in a wide temperature range of 600–1800 K. A model system comprises a tower, a multi-aperture receiver with compound parabolic concentrators, and heliostat sub-fields. Optical modeling is performed using in-house developed Monte-Carlo ray-tracing programs. The heliostat sub-field geometrical configuration, the number of receiver apertures and optical properties of reflective surfaces are varied in the parametric study. Increasing the number of apertures from one to four increases the maximum net receiver power from 116 MW to 332 MW. The use of more than four apertures results in only limited further gain of the net receiver power but significantly decreases the overall optical efficiency and the solar-to-thermal efficiency. The optimal temperature for the maximized annual solar-to-exergy efficiency is found in the range of 1100–1200 K. This optimal temperature decreases slightly with an increasing number of apertures.
Publisher: Elsevier BV
Date: 10-2019
Publisher: Elsevier BV
Date: 10-2022
Start Date: 09-2022
End Date: 09-2026
Amount: $654,642.00
Funder: Australian Research Council
View Funded ActivityStart Date: 06-2016
End Date: 12-2021
Amount: $430,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 02-2019
End Date: 12-2023
Amount: $440,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 01-2015
End Date: 12-2021
Amount: $813,622.00
Funder: Australian Research Council
View Funded Activity