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Adsorption using porous adsorbents is widely applied in carbon dioxide (CO2) capture due to its potential energy saving with low operating cost. Metal-organic frameworks (MOFs) are preferable over conventional adsorbents as MOFs have tunable structure properties. Organic linkers from phytochemical-based give a new idea in forming MOFs. Gallic acid is classified under phytochemicals can act as an alternative organic linker in a new family of hybrid framework materials due to low cost, low toxicity, easy availability and naturally abundant. Due to unique property of MOFs that can be tailored, screening using systematic tool is very important. Molecular modeling is proven to play a crucial role in providing an estimation on adsorption capacity, selectivity and adsorbent selection. Grand Canonical Monte Carlo (GCMC) method via Sorption module in Material Studio was performed to compute loading curves of CO2 and methane (CH4) in MOFs. Based on the simulation results, it shows that gallate-based MOFs can be a new promising adsorbent in CO2 capture as the predicted CO2 loading is significantly higher than CH4. The highest predicted CO2 adsorption capacity is achieved by Mg-gallate and the lowest is by Ag-gallate with 7.79 mmol/g and 6.35 mmol/g respectively. The applicability of gallic acid to act as an alternative linker is relevant for practical applications.

In the electrolyte application for dye sensitized solar cells, utilization of ionic liquids is getting the highlights to replace volatile organic solvent thanks to their low volatility, thermal and electrochemical stability. The iodide/triiodide redox electrolyte is the preferred choice for this application, hence numerous iodide-based ionic liquids have been explored and reported. On the contrary, the transport properties of triiodide based ionic liquid is often lack of reporting despite of having an equal influence on the overall viscosity and ionic conductivity of the electrolyte. In this study, three alkylimidazolium triiodide ionic liquids were synthesized from the respective alkylimidazolium iodide ionic liquids precursors and their physicochemical and conductivity properties are reported. 1H NMR analysis showed a slight shifting of position of the resonances of triiodide based alkylimidazolium ionic liquids as compared to their precursors due to less electronegativity nature of triiodide anion. The formation of triiodide-based imidazolium ILs have dramatically altered the transport properties in which the ionic liquids obtained are of low viscosity and high ionic conductivity.

Transforming carbon dioxide (CO2) into value-added products through electrochemical reduction reaction (CO2ERR) is a promising technique due to its potential advantages using renewable energy. The main challenge is to find a stable catalytic system that could minimize the reaction overpotential with high faradaic efficiency and high current density. Ionic liquids (ILs) as electrolyte in CO2ERR have attracted attention due to the advantages of their unique properties in enhancing catalytic efficiency. For better performance, a systematic understanding of the role of ILs as electrocatalyst is needed. Therefore, this paper aims to correlate the performance of ILs as co-catalyst in (CO2ERR) with the lowest unoccupied molecular orbital (LUMO) energy level and the interaction energy as predicted by quantum chemical calculation using Conductor like Screening Model for Real Solvents (COSMO-RS) and Turbomole. The results show strong linearity (R2=0.98) between hydrogen bond energy (HB) and LUMO values. It is demonstrated that as HB increases, the LUMO value decreases, and the catalytic activity for CO2ERR also increases. This result allows further understanding on the correlation between the molecular structure and the catalytic activity for CO2ERR. It can serve as a priori prediction to aid in the design of new effective catalysts.

In order to identify the best possible reaction media for performing H2S conversion, a total number of 300 different ILs from a combination of 20 cations and 15 anions were screened via COSMO-RS model simulations. By COSMO-RS method, thermodynamic and physicochemical properties of 300 ILs such as Henry’s law constants, activity coefficient, selectivity, capacity and performance index are obtained and analyzed. Thus, by comparing the performance of ILs via COSMO-RS, a series of TSILs containing cation of [P66614] with metal chloride anions such as Fe, Ga and Sn were chosen and selected for synthesis based on their performance predicted by COSMO-RS and their economic values. Consequently, the physiochemical properties such as density, viscosity, thermal properties, as well as H2S absorptive oxidation performances in those TSILs will be systematically investigated.