Prof. Lei Xing
Institute of Green Chemistry and Chemical Engineering, Jiangsu University, China
Title: Functionally graded electrodes and segmented design toward the commercialization of PEM (proton exchange membrane) fuel cells
Abstarct: Proton exchange membrane (PEM) fuel cells are promising energy converting devices owing to their high energy density, great efficiency and zero emission. As the most important component, the membrane electrode assembly (MEA) have obtained intensive attentions of research with respect to the improved performance, reliability and durability, as well as the reduced cost. During PEM fuel cell operating, the desired electrochemical reaction and mass transport rates vary within the MEA due to the inhomogeneous spatial distribution of reactants and products. The design of functionally graded electrode compositions and operating conditions is considered as a promising strategy to reduce the usage of precious Pt-based catalysts and improve cell performance.
A promising strategy is to match the electrochemical reaction rate with the mass transport rate of reactants using functionally graded electrode and segmented fuel cell design, in which the Pt loading, Nafion content, GDL porosity and temperature are non-uniformly distributed along both the in-plane gas flow direction and the through-plane gas diffusion reactions. Specifically, we manufactured the segmented fuel cell by isolating the graphite plate by several sections with polycarbonate. The functional components and operating temperature within each section are carefully controlled to form a linear gradient along the gas flow direction from the inlet to outlet. A two-phase flow CFD model is developed to further investigation of the optimal gradients of functional components and operating temperature.
A systematical design of the gradients of functional components and operating temperature achieves an improved cell performance and saves the usage of Pt-based catalysts without worsening the homogeneity of current density. The proposed state-of-art strategy is considered as a promising solution to the commercialization of PEM fuel cells.
Assoc. Prof. Md. Hasanuzzaman
Higher Institution Centre of Excellence (HICoE), University of Malaya, Malaysia
Title: Global Challenges in the Energy Sector: Prospects of Solar Thermal Energy
Energy is necessary for industrial production and, therefore, economic growth. Global energy supply predominantly comes from fossil fuel based resources that are the major contributor of CO2 emission. Earth's atmosphere has now been enshrouded by unrestrained emission of CO2 leading to global warming, in other words climate change. According to a report from the Intergovernmental Panel on Climate Change (IPCC), global warming will continue to get worse unless there is a rapid shift towards clean energy and quick cut off in CO2emission rate. While 350 ppm of CO2 in the atmosphere is a safe norm 450 ppm represents a high risk state. Global urgency to hold back CO2emission rate drives for alternative clean and sustainable energy sources, wherein solar energy comes in the first place due to its inexhaustible supply and environmental friendly notion. Presently, most industries burn oil, natural gas, coal or use electricity to produce process heat for the preparation or treatment of materials. However, a large portion of industrial process heat is sufficiently low temperature that can easily be supplied by solar energy. Among other solar technologies solar thermal is the most promising alternative for generating process heat as it can cover a wide temperature range of industrial requirements from low to medium temperature applications. Well-engineered integration of solar thermal heating with conventional heating systems is capable to ensure sustainable energy supply in industries, which will not only perk up environment by alleviating the dependency on fossil fuel but also increase the revenue.