CHUAH Gaik Khuan

CHUAH Gaik Khuan

Associate Professor

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Research

ORCID: 0000-0002-4739-9405

ResearcherID: H-8677-2013

 

Research Interests

Our main research area is on heterogeneous catalysis:

• Applications of zeolites in fine chemicals synthesis
• Green chemistry and catalysis
• Mechanochemistry-assisted synthesis
• Inorganic ion-exchangers
• Photocatalysts in water remediation and synthesis

 

Research Highlight

Zeolites are versatile catalysts not only for large scale petrochemical processes but also in applications related to fine chemicals synthesis, biomass conversion and CO2 utilization. Introduction of mesopores and heteroatoms opens up additional applications. Heteroatoms in the crystalline framework create active sites where the diversity in the coordination offers tunability in acidity and redox properties. Their framework locations within the unit cell and their open/closed nature greatly influence the catalytic ability. Depending on the synthesis conditions, the properties of the pore walls can vary from hydrophobic to hydrophilic which affects the confinement of reactant and solvent molecules within the well-ordered pores. We synthesize heteroatom zeolites from traditional solvent-based methods to the more sustainable routes of post-synthesis and mechanochemistry. The properties of the zeolites formed by the different methods are compared and the impact on selected catalytic reactions is investigated.

 

Figure 1 Hosting of (a) tri- (b) tetra- and (c) pentavalent heteroatoms in the zeolitic framework and (d) synthesis protocols and tunable properties of zeolites.

Table 1. Examples of cascade reactions catalyzed by Zr-Beta

Teaching Contributions AY2023/2024

• CM3253 Materials Chemistry 1

 

Representative Publications   

• Chen, Y.; He, L.; Tan, H-R.; Lin, X.; Jaenicke, S.; and Chuah, G. K., Molten salt synthesis of a highly crystalline graphitic carbon nitride homojunction from a deep eutectic solvent for selective photocatalytic oxidation, J. Mater. Chem. A, 2023, 11, 12342–12353.
• Samsudin, I. B.; Jaenicke, S.; and Chuah, G. K., Conversion of Ethanol to Butadiene over Binary MgO-SiO2 Mixed Oxides Prepared by the Ammonia Evaporation Method, Chemistry, 2023, 5, 544–558.
• Zhang, H.; Samsudin, I. B.; Jaenicke, S.; and Chuah, G. K., Zeolites in catalysis: sustainable synthesis and its impact on properties and applications, Catal. Sci. Technol. 2022, 12, 6024–6039.
• Zhang, H.; Zhong, L.; Samsudin, I. B.; Okumura, K.; Tan, H.-R.; Li, S.; Jaenicke, S.; and Chuah, G. K., Mg-stabilized subnanometer Rh particles in zeolite Beta as highly efficient catalysts for selective hydrogenation. J. Catal. 2022, 405, 489–498.
• Zhang, H.; Quek, Z. J.; Jaenicke, S.; Chuah, G. K., Hydrophobicity and co-solvent effects on Meerwein-Ponndorf-Verley reduction/dehydration cascade reactions over Zr-zeolite catalysts. J. Catal. 2021, 400, 50–61.
• Roslan, I. I.; Zhang, H.; Ng, K. H.; Jaenicke, S.; Chuah, G. K., A Visible Light and Iron-mediated Carbocationic Route to Polysubstituted 1-Halonaphthalenes by Benzannulation using Allylbenzenes and Polyhalomethanes.  Adv. Synth. Catal. 2021, 363, 1007-1013.
• Zhang, H.; Chiew, J. L. T.; Jaenicke, ; Gondal, M. A.; Dastageer, M. A.; Basheer, C.; Chuah, G. K., BiOBrnI1-n solid solutions as versatile photooxidation catalysts for phenolics and endocrine disrupting chemicals. Catal. Today 2021, 375, 547-557.
• Zhang, H.; Tan, H.-R.; Jaenicke, S.; Chuah, G. K., Highly Efficient and Robust Cu Catalyst for Non-Oxidative Dehydrogenation of Ethanol to Acetaldehyde and Hydrogen. J. Catal. 2020, 389, 19–28.
• Cheng, Y.; Chui, S.-Y. S.; Wang, X. D. (T.); Jaenicke, S.; Chuah, G. K., One-pot synthesis of layered disodium zirconium phosphate: crystal structure and application in the remediation of heavy metals-contaminated wastewater. Inorg. Chem. 2019, 58, 13020−13029.
• Cheng, Y.; Zhang, H.; Jaenicke, J. A.; Tan, C. P. E.; Chuah, G. K., Minimalistic Synthesis of α-Zirconium Diammonium Phosphate and Zirconia for Applications in Ion Exchange and Catalysis. ACS Sustainable Chem. Eng. 2019, 7, 895–904.