Graphene oxide supported layered double hydroxide hybrids: Synthesis and applications

7^th Annual Congress on Materials Research and Technology

February 20-21, 2017 Berlin, Germany

Mohamed Mokhtar

King Abdulaziz University, Saudi Arabia
National Research Centre, Egypt

Scientific Tracks Abstracts: J Material Sci Eng

Abstract :

Layered double hydroxides (LDHs) are class of two-dimensional (2D) anionic clays with brucite-like layered structure and intercalated anions. LDH materials can be converted to mixed metal oxides (MMO) nanocomposites after the thermal treatment. The MMO nanocomposites made from LDH precursors showed a uniform dispersion of metal ions as well as a high surface area in comparison to the metal oxides made by traditional chemical and physical method. Graphene oxide (GO) provides light-way, charge complementary, two-dimensional (2D) material that interacts effectively with 2D LDHs to form a hydride materials that improves the both the adsorption capacity of LDHs and their catalytic performance towards carbon-carbon coupling reaction. Recently, developing an efficient protocol for the synthesis of such materials was the interest of many researchers. Our group of research succeeded to synthesize a series of different LDHs /GO hybrids utilizing simple precipitation of LDH nanoparticles onto GO under controlled pH and temperature conditions. During the precipitation of positively charged LDH onto negatively charged GO, the mutual electrostatic interactions drive the self-assembly of hetero-structured nano-hybrids, in a â�?�?layer-by-layerâ�? fashion. The CO2 adsorption capacity and multi-cycle stability of the LDH were both increased when supported onto GO because of enhanced particle dispersion. More recently, CuAl LDH/GO and CoAl LDH/GO hybrid materials with different LDH compositions were prepared. The as-synthesized hybrids and calcined composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal analysis (TG), Brunauer-Emmett-Teller (BET-surface area), temperature programmed reduction (TPR) measurements. CuAl- and CoAl-LDHs have shown excellent yields (91% and 98%, respectively) in 25 min. reaction times. However, the mechanical properties of GO allows an enhancement of the stability of the catalyst that can be separated and reused in the reaction several times with a loss of activity as low as 70% of its initial value after five cycles.

Biography :

Mohamed Mokhtar is a Professor of Physical Chemistry at King Abdulaziz University (KAU). He was an Associate Professor at National Research Centre, Egypt, where he started his preliminary steps in the scientific research area. He is interested in advanced materials with special interest in their application in heterogeneous catalysis. In addition, he is Specialist in “Catalyst and adsorbent characterization with particular expertise in adsorption measurements”. He has published over 80 refereed publications and many international patents. He has numerous collaborative projects with public and private sector organizations.

Email: mmoustafa@kau.edu.sa