YCN Research in Spot: MAX phase and MAB phase derived MXenes for energy storage application by Nick Goossens

Two-dimensional graphene-like materials have been a hot research topic in the past years in search of the Holy Grail of electrochemical energy storage. That is, a material which is able to reversibly store very high amounts of charge at a very high (dis)charging speed. Unfortunately, most known materials satisfy just one of the two conditions

MXenes offer the potential to combine the best of both worlds. They are essentially two-dimensional sheet-like binary transition metal carbides. Their 2D nature provides them substantial surface area and, consequently, large energy storage capacity and favourable kinetics. Moreover, the electrochemical activity of the transition metals induces pseudo-capacity, resulting in fast electron transfer. 

Our research is focused on the two-step synthesis of these MXenes. First, MAX- and MAB-phases are produced by reactive powder sintering. These are nanolaminated ternary ceramics consisting of a transition metal (M), an A-group element (A), carbon/nitrogen (X) or boron (B). Their atomic structure closely resembles that of well-prepared lasagne: the layers of pasta resemble atomic layers of a binary MX-carbide/nitride or MB-boride, which are separated by an atomic layer of A-atoms, resembling the tasty tomato sauce. The second step involves the selective leaching of the A-atoms with the goal of achieving free-standing MXene or MBene sheets. Completing the analogy of the lasagne: we intend to isolate the pasta layers by selectively eating the sauce. Our goal is to expand the list of experimentally obtainable MAX and MAB phases and tailor their structure and composition to ensure maximal electrochemical activity of their MXene derivates. These MXenes, in turn, might be found in future generation energy storage technology.

Nick Goossens
Winner of the 2019 ECerS Student Speech Contest

FWO fellow fundamental research
KU Leuven
Secretary of the POC Materiaalkunde
ABAP-representative of the Materials Engineering Department Council
ABAP-representative of the Materials Engineering Department Board

Department of Materials Engineering
Kasteelpark Arenberg 44 box 2450
B-3001 Heverlee
Belgium
Office 00.11
phone: +32 16 32 58 34
e-mail: nick.goossens@kuleuven.be