ENGINEERING HDR SEMINAR SERIES (46/2013) : Design and Development of Graphene-based Photocatalysts for Reduction of CO2 into Valuable Chemicals

Mr Ong Wee Jun, postgraduate student from School of Engineering, Monash University Sunway Campus

Date: 2013-10-10
Time: 15:00 to 16:00
Venue: Engineering Meeting Room 1, 5-4-22


The continuously increasing concentration of carbon dioxide (CO2) in the atmosphere is one of the most serious problems which contributes to global warming and climate change. Till now, many great strides are made to reduce the regional and global CO2 emissions, but yet any specific solutions are found to effectively control the CO2 emission. Among various green earth and renewable energy projects underway, semiconductor photocatalysis has gained considerable interdisciplinary research fascination for their diverse potentials in energy and environmental applications. Photocatalytic reduction of CO2 into useful hydrocarbons under visible light irradiation is a promising solution to circumvent both energy and environmental crisis by recycling CO2 to energy feedstock. Among all photocatalysts, TiO2 is by far the most researched photocatalytic material due to its long term stability, strong oxidizing power, corrosion resistant, non-toxicity and cost effectiveness. However, TiO2 suffers from a narrow light-response range due to its large band gap energy which can only be excited under UV light irradiation. Also, the rapid recombination of photogenerated charge carriers during the photocatalytic process greatly limits the TiO2 efficiency. Consequently, the state-of-the-art technology is far from being optimal and there are still considerable breakthroughs to be made before it can be considered as a viable economical process. A variety of modifications have been employed to enhance the catalytic performance of TiO2 photocatalysts by harnessing visible light or sunlight, which is a green source of energy to mimic the natural photosynthesis in plants. Recently, the incorporation of carbon nanomaterials with TiO2, in particular graphene, has garnered incessant research attention for the preparation of composite materials and photocatalytic applications in sustainable solar energy utilization owing to its excellent mobility of charge carriers and large surface area. Furthermore, the most recent being the synthesis of TiO2 crystals with highly reactive {001} facets has sparked cosmic interest seeing that crystals exhibit fascinating surface-dependent properties. Therefore, in this work, a combined approach of graphene and the introduction of high energy {001} facets of TiO2-based composites was designed for the conversion of CO2 into energy-rich fuels via photocatalytic process for a sustainable energy future. The nanocomposite is anticipated to be developed as a robust means to address various energy and environmental-related issues to achieve a pollution-free environment.

About the Speaker

Mr. Ong Wee Jun graduated with Bachelor of Engineering (Chemical Engineering with Honours) from Monash Unversity Malaysia in 2012. He was the recipient of Best Graduate Award of Bachelor of Engineering (Chemical Engineering) in 2012. He joined Monash University in the same year for postgraduate studies under the supervision of Dr. Chai Siang Piao and Dr. Yong Siek Ting. His research focuses on the design and development of highly efficient graphene-based semiconductor photocatalysts and graphene-like carbon nitride nanosheets for the conversion of carbon dioxide into energy-rich fuels for a sustainable energy future, as part of huge efforts to combat the ever-increasing CO2 emission.