Overview
Mr. Guillermo Menendez Rodriguez is currently a second year PhD student in the School of Engineering at Cardiff University, as part of the Magnetic and Materials research group under the supervision of Doctor Victoria Garcia-Rocha, Professor Gao Min and the Head of the School of Engineering Professor Sam Evans. Before beginning his PhD studies, he completed the Undergraduate Degree in Industrial Engineering at the Technical University of Madrid (2014), as well as a double degree program covering the two-year Master in Industrial Engineering at the same university and the one-year Master in Materials Science and Engineering at the Illinois Institute of Technology in Chicago, USA (2016). Additionally, he spent six months as a researcher in training at the IMDEA Energy Institute in Madrid before joining Cardiff University.
Research
Research interests
Working on the development of bioinspired graphene/ceramic composites with a high level of hierarchy, Studying the feasibility of embedding a bioinspired graphene network into a bulk ceramic material, leading to tougher, stronger composite materials with additional functional properties
Thesis
Developing bioinspired graphene/ceramic composites
Graphene is currently the benchmark of two-dimensional materials due to its combination of low density, flexibility and great mechanical strength, while displaying unmatched electrical and thermal conductivities. Graphene-reinforced composites appear a promising vehicle to spread graphene throughout the industry and take advantage of its outstanding properties. There have been numerous works aiming to introduce graphene reinforcements in ceramic composites by conventional powder processing or through colloidal and sol-gel solutions. However, with these approaches the internal structure of the composite is not carefully controlled, as the two phases are mixed in a random fashion resembling concrete or clay. Tailoring the internal hierarchy of these materials at different length scales seems essential. This approach can be witnessed in a plethora of natural composites, such as seashells or bones, in which weak constituents achieve a combination of toughness and strength that vastly outperform that of random mixing processes.
My research aims to develop and manufacture bioinspired graphene/ceramic composites by joining two concepts: The outstanding properties of graphene sheets obtained from graphene oxide (a precursor derived from the chemical modification of graphite), while implementing a bioinspired hierarchy achieved by freeze-casting and wet chemistry processing. Before such material is obtained, several key outcomes need to be tackled. The first steps would cover the development of single phase graphene networks by freeze-casting suspensions with an adequate concentration and additives, proving the feasibility of using graphene oxide (GO) as the graphene precursor to obtain an electrically conductive network after an annealing process. A valid processing route must be identified through which the ceramic and the graphene phase can coexist in a bulk bioinspired composite, maintaining coherence and good interfacial properties. In a later stage, the use of advanced sintering techniques (Spark Plasma Sintering) will be needed to produce dense composites, after which characterisation and mechanical testing is required to study its fracture toughness, strength, wear resistance or electrical conductivity.
Funding source
Engineering and Physical Sciences Research Council (EPSRC)
Supervisors
Publications
2022
- Menendez Rodriguez, G. 2022. Novel water-based processing route for producing structured graphene/alumina composites. PhD Thesis, Cardiff University.
2021
- Eze, M. C. et al. 2021. Optimum silver contact sputtering parameters for efficient perovskite solar cell fabrication. Solar Energy Materials and Solar Cells 230, article number: 111185. (10.1016/j.solmat.2021.111185)