[P2-82] Modelling and analysis of SiO2 interfaces of non-firing solids
Generally, ceramics are manufactured by using sintering process. However, this process needs high temperature and loss a lot of fuels. CO2 emission in the process is also need to improve. So, non-fire process is focused to make ceramics products.
For non-fire process, surfaces of SiO2 particles are polished and put hydrogen on the activate surfaces. These SiO2 particles are compressed and put into water that is non-fire process of ceramics. In this study, SiO2 interface models were constructed for molecular dynamics simulation. Interactions between SiO2 and H2O were presented by using ReaxFF potential. At first, SiO2 interfaces model without OH as end groups were conducted. By put water molecules between SiO2 interfaces, some atoms were changed their combinations. Some of them achieved lower potential energy through the simulation. It is seemed that a part of non-fire process was reproduced. For example, hydrogen atom connected the oxygen atom of SiO2. However, connection of SiO2 did not observed over SiO2 interfaces.
Then, SiO2 interfaces model with OH as end groups were conducted. At relaxation of the models, SiOH exists in the model. After relaxation, water molecules were put into the surfaces. However, changes of connection between SiO2 and H2O or SiO2 interfaces did not observed. Energetic or structural stability of SiOH surfaces were seemed to effect the result.
Distance of interfaces, conducting compressed SiO2 including OH as end groups models might be key to improve the ability of reaction between atoms.
For non-fire process, surfaces of SiO2 particles are polished and put hydrogen on the activate surfaces. These SiO2 particles are compressed and put into water that is non-fire process of ceramics. In this study, SiO2 interface models were constructed for molecular dynamics simulation. Interactions between SiO2 and H2O were presented by using ReaxFF potential. At first, SiO2 interfaces model without OH as end groups were conducted. By put water molecules between SiO2 interfaces, some atoms were changed their combinations. Some of them achieved lower potential energy through the simulation. It is seemed that a part of non-fire process was reproduced. For example, hydrogen atom connected the oxygen atom of SiO2. However, connection of SiO2 did not observed over SiO2 interfaces.
Then, SiO2 interfaces model with OH as end groups were conducted. At relaxation of the models, SiOH exists in the model. After relaxation, water molecules were put into the surfaces. However, changes of connection between SiO2 and H2O or SiO2 interfaces did not observed. Energetic or structural stability of SiOH surfaces were seemed to effect the result.
Distance of interfaces, conducting compressed SiO2 including OH as end groups models might be key to improve the ability of reaction between atoms.