Prof. Hamidi Abdul Aziz
Universiti Sains Malaysia, Malaysia
Title: The science and engineering of landfill leachate pollution control
Most of the present solid waste landfill sites in developing countries are practising either unsanitary landfilling or open dumping. One of the main concerns of landfilling is leachate production. Leachate is created when water passes through the waste body. The water mainly occurs from rain and through waste degradation process. Leachate contains significant amounts of organic compounds, heavy metals, ammonia, and many other hazardous chemicals. COD, NH3-N, and colour are among the difficult parameters which are hard to be completely removed. Proper treatment facilities are needed before leachate can be released to the environment. The treatment depends on the leachate qualities, operation and capital costs, and regulations. Up to now, researchers worldwide are still looking for a total solution to the leachate problem. Multiple-stage treatments are normally necessary through blend of biological, physical, chemical and their combinations. The science and engineering aspects in treating landfill leachate treatment will be shared in this paper. Special consideration will also be made on the application of leachate treatment for semi-aerobic landfill in developing countries. Its biodegradability is low and riched in COD, NH3-N, and colour.The paper also highlights some of the challenges in the overall leachate treatment processes.
Assoc. Prof. Md. Akhtaruzzaman
The National University of Malaysia
Research area: New cell structure, Intelligent materials, Solar cells, Photovoltaic device
Title: The Advancement of Inorganic Hole Transport Materials Towards Emerging ThirdGeneration Thin Flim Solar cells
Organic-inorganic hybrid solar cells (OIHSCs) such as perovskite solar cells (PSCs), dye-sensitized solar cells (DSCs) and bulk heterojunction solar cells (BHJSCs) have a growing interest in thin-film photovoltaic technology due to their lightweight, flexible and low-cost manufacturing processes [1,2]. However, there are a number of issues that currently restrict the commercialization of OIHSCs due to their efficiency, stability and reproducibility and fabrication in a large area. Numerous hole transport materials (HTMs) such as spiro-OMeTAD, poly(triarylamine), PEDOT: PSS, which are mostly organic derivatives, have already been established and incorporated into OIHSCs. Organic HTMs are unstable in water, heat and light, which ultimately reduces the stability of OIHSC. The synthesis and complex purification costs of organic hole transport materials are also another drawbacks in exiting OIHSCs. As a result, various inorganic metal oxides such as CuO, MoO3, WO3, NiOx, Cr2O3, etc. as HTMs have promising outcomes such as improving the carrier transporting properties within solar cell devices with higher life-time and stability. Among them, NiOx has recently gained significant attention due to its excellent optical, and electrical properties, along with its good chemical stability and easy fabrication of optically transparent dense films by several techniques. To further enhance the operational stability of OIHS, simultaneous system engineering such as interface modification of HTL / absorber layer, tuning of the crystallinity, morphology, and defect engineering should be considered to realize their full potential. Various experimental techniques would be investigated to find both the stability and performance of organic-inorganic hybrid solar cells towards the flexible solar energy revolution.
Prof. Qing Liu
Shandong University of Science and Technology
Research area: Energy Catalysis
Title: coming soon...