MoS2 - New material in green energy industry
Today, the energy war is taking place very complicatedly and the fossil energy resources are gradually depleted globally. The United Nations Climate Change Summit (COP21) committed and approved a general agreement to limit global warming and demand zero greenhouse gas emissions by 2030. This prioritizes using low-carbon technologies and processes that use carbon as raw materials for production. Therefore, the search for clean, renewable and environmentally friendly energy sources to replace fossil energy with low or zero greenhouse gas emissions is a topic of research interest.
Different phase structures of MoS2 (a), and surface electron microscopy of MoS2 nanosheets with several monolayers (b)
Hydrogen fuel (H2) with high specific heat is considered a clean, endless, and environmentally friendly renewable fuel source. Products that burn H2 fuel only produce steam, do not generate toxic gases (COX, NOX, SO2) or impurities harmful to the environment, affecting human health like combustion products from gasoline or diesel oil. In particular, H2 gas fuel is mainly prepared from water splitting reactions through photoelectrochemical processes under the support of catalysts and light, so H2 fuel will be an inexhaustible source of energy, mainly in the future.
The development of materials science to help search for catalysts to increase the efficiency of the reaction to separate H2/O2 gas from water, thermal and chemical stability, and environmental friendliness, is attracting many research groups to find new materials. Among them is emerging research topic MoS2 materials with low-dimensional structure (2D, 0D) containing many active centers for many different applications.
Synthesis of MoS2 by hydrothermal method
According to Dr. Nguyen Tien Dai, the research team has found a hydrothermal process to successfully synthesize MoS2 materials with 2D thin film, mushroom-shaped ear, quantum dots (0D) structures on glass, Si, ITO substrates using two precursors Na2MoO4 and NH4SCN in the temperature range from 80 degrees C to 200 degrees C. These are two precursors with low cost, easy to buy and easy to implement at the existing equipment conditions in the laboratories at the Vietnam Academy of Science and Technology. In which the temperature of 180 degrees Celsius is the most suitable for the synthesis of 2D structural thin films. The structure, morphology, and thickness of 2D-MoS2 thin films can be controlled by varying the synthesis temperature (in the range of 80°C to 200°C) and hydrothermal time.
Synthesis of MoS2 crystal microstructure by hydrothermal method (a) and measurement of optical properties of MoS2 materials on fastFLIM, VAST system (b)
The obtained research results have high applicability, suitable for the research direction of the environment, green energy industry, treatment of toxic substances in wastewater, and searching for materials to replace H2 fuel cells. The topic is topical and of high scientific and practical significance. Therefore, the research team wishes to cooperate with research units inside and outside the Vietnam Academy of Science and Technology, and production facilities in the coming period to continue developing research and creating scientific products ready for commercialization.
Translated by Phuong Huyen
Link to Vietnamese version
