Nilofar Asim

The role of physical techniques on the preparation of photoanodes for dye sensitized solar cells

Dye sensitized solar cells (DSSCs) have attracted numerous research, especially in the context of enhancing their efficiency and durability, due to the low-cost and environmentally friendly nature of photovoltaic (PV) technology. The materials in DSSCs are vital towards the realization of these goals, since many of the important components are influenced by their respective preparation and deposition methods. This review aims to detail the research and development aspects of the different physical methods with the purpose of evaluating their prospects and corresponding limitations. The diversity of consideration and criteria includes thin film applications, material characteristics, and process technology that need to be taken into account when selecting a specific deposition method. Choosing a deposition method is not as simple as it seems and is rendered quite complicated due to various factors. Usually, a researcher will evaluate techniques based on factors such as the different preparations and deposition technology with materials’ and substrates’ type, specified applications, costs, and efficiencies.

Photocatalytic degradation of methylene blue under UV light irradiation on prepared carbonaceous TiO2.

This study involves the investigation of altering the photocatalytic activity of TiO2 using composite materials. Three different forms of modified TiO2, namely, TiO2/activated carbon (AC), TiO2/carbon (C), and TiO2/PANi, were compared. The TiO2/carbon composite was obtained by pyrolysis of TiO2/PANi prepared by in situ polymerization method, while the TiO2/activated carbon (TiO2/AC) was obtained after treating TiO2/carbon with 1.0 M KOH solution, followed by calcination at a temperature of 450°C. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TG-DTA), Brunauer-Emmet-Teller (BET), and UV-Vis spectroscopy were used to characterize and evaluate the prepared samples. The specific surface area was determined to be in the following order: TiO2/AC > TiO2/C > TiO2/PANi > TiO2 (179 > 134 > 54 > 9 m2 g−1). The evaluation of photocatalytic performance for the degradation of methylene blue under UV light irradiation was also of the same order, with 98 > 84.7 > 69% conversion rate, which is likely to be attributed to the porosity and synergistic effect in the prepared samples.

Annual energy usage reduction and cost savings of a school: end-use energy analysis.

Buildings are among the largest consumers of energy. Part of the energy is wasted due to the habits of users and equipment conditions. A solution to this problem is efficient energy usage. To this end, an energy audit can be conducted to assess the energy efficiency. This study aims to analyze the energy usage of a primary school and identify the potential energy reductions and cost savings. A preliminary audit was conducted, and several energy conservation measures were proposed. The energy conservation measures, with reference to the MS1525:2007 standard, were modelled to identify the potential energy reduction and cost savings. It was found that the schools usage of electricity exceeded its need, incurring an excess expenditure of RM 2947.42. From the lighting system alone, it was found that there is a potential energy reduction of 5489.06 kWh, which gives a cost saving of RM 2282.52 via the improvement of lighting system design and its operating hours. Overall, it was found that there is a potential energy reduction and cost saving of 20.7% when the energy conservation measures are earnestly implemented. The previous energy intensity of the school was found to be 50.6 kWh/m2/year, but can theoretically be reduced to 40.19 kWh/mm2/year.

Perspective of Nanomaterials in Solar cell

Reducing cost and increasing efficiency are the principal drivers in photovoltaic technology. Nanotechnology has shown particular promise since it can offer solution to both problems either by improving the existing technologies or helping to replace them with alternative solutions. Nanomaterials can contribute from different ways. The solar cell designs and enhancements play important role in their performance and categorized by the type of nanostructure utilized. This review paper focuses on different possible contribution of nanomaterials in solar cell and describes their promising role and their obstacles.

Investigation of Photocatalytic Activity of TiO2-PANi Nanocomposites

In this paper the photocatalytic activity of TiO2-PANi nanocomposites prepared using two different In-situ polymerization methods have been investigated. The same pressure, temperature, precursors, mole ratio, and solvent have been employed for preparation of nanocomposites. The synthesized nanocomposites were characterized by FESEM, XRD and FTIR. Results revealed the successful preparation of TiO2- PANI nanocomposites. TiO2-PANi nanocomposite synthesized using method 2 showed very well dispersed TiO2 nanoparticles on the surface of PANi. There is no agglomeration of TiO2 nanoparticles in PANi matrix. The photocatalytic activities of nanocomposites were evaluated by using photo degradation of Methylene Blue (MB) in aqueous solution under UV irradiation. These nanocomposites exhibit much higher photocatalytic activity compared with TiO2.

OVERVIEW OF CARBON DIOXIDE SEPARATION TECHNOLOGY

One of the most urgent environmental issues of our time is to lower the concentration of greenhouse gases in the atmosphere by decreasing CO2 emission. Carbon capture and storage has been introduced as an option in reducing these harmful CO2 emissions. CO2 separation from gas streams has been done using a variety of physical, chemical and biological technologies and methods. These technologies allow large-scale CO2 separation in different industries including coal-fired power plants, refinery and fertilizer industries. Hence, this article reviews different separation methods, such as absorption, adsorption, and membrane-based separation. Other concepts, such as biological separation are also introduced.

Perspective of Agriculture Wastes Usage as a Resource

Investigations and phisibilty studies on using agriculture wastes as a resource for producing energy and materials is regarded insufficient and unsatisfactory. Nonetheless, the utilization of the agriculture solid wastes is suggested a viable solution to reduce pollution and to bring economical benefits. This review study emphasis on the importance of conducting experimental characterization in order to determine which application is suitable for determined waste material. These characterizations could suggest the necessary treatments or methods required to make these materials more efficient as a resource for energy and materials applications. This tailoring may enable researcher to optimize both costs and technical performances of agriculture solid waste as a resource for different application.