The 'power-to-X' strategy aims at generating value-added chemicals and fuels through electrochemical conversion, for example by splitting water into O2 and H2 via the oxygen and hydrogen evolution reactions. This approach can generate climate-neutral fuel and sustainable chemical synthesis using renewable energy sources, effectively storing energy and coupling different sectors. For the underlying electrochemical reactions, electrocatalyst materials are required, which reduce the amount of energy needed to drive the reactions efficiently and to steer the product selectivity. These materials must be made of earth-abundant and safe materials, and must be stable under reaction conditions. In the Inorganic Materials Science Group, we approach this fundamental research question through a special materials-by-design approach and through novel characterization tools.

The key scientific questions for this PhD project revolve around a new class of two-dimensional materials, called MXenes, which promise high activity and selectivity for a multitude of reactions. MXenes are 2D carbides and nitrides that can be synthesized through wet etching of MAX phases (transition metal carbides or nitrides with layers of "A-elements" (groups 13 and 14 in the periodic table)), followed by transfer to arbitrary substrates. MXenes have the general formula Mn+1XnTx, where M is an early transition metal, X is C or N, and T is a surface termination functional group. We will investigate, e.g., Ti3C2Tx and Mo2CTx.

As is the case for most electrocatalyst materials, the properties of the MXene surface during operation are unknown. But these properties dictate the reactivity, hampering materials design and exploitation for energy transformation and storage and chemical synthesis because predictive power is limited. We aim to overcome this lack in understanding using newly-developed interface-sensitive spectroscopies that probe the surface composition and electronic structure under reaction conditions ("operando"). Only with such interface-sensitive operando information can we fully understand the underlying reaction mechanisms and devise much-needed prescriptive design rules.

The research will be pursued by one PhD student at the University of Twente, in close collaboration with a team of researchers pursuing development of operando, interface-sensitive X-ray photoelectron spectroscopy. The PhD student will be supervised Asst. Prof. Chris Baeumer and Prof. André ten Elshof with the four-eye-principle of the Twente Graduate School.

• You are a highly motivated, enthusiastic, and self-driven researcher (F/M/D).
• You have a MSc degree in Chemistry, Physics, Materials Science or equivalent, with excellent experimental skills.
• You have a keen interest in Materials Science, Electrochemistry and bridging Chemistry and Physics.
• You have strong analytical skills and can interpret complex data in a broader scientific context.
• You are fluent in English.

You will be appointed on a fulltime position for 4 years, with a qualifier in the first year, within a very stimulating scientific environment. The university offers a dynamic ecosystem with enthusiastic colleagues. Salary and conditions are in accordance with the collective labor agreement for Dutch universities.

• Monthly salary ranging from € 2.541,- gross at the start to € 3.247,- gross in the 4th year.
• Excellent benefits including a holiday allowance of 8% of the gross annual salary, an end-of-the-year bonus of 8.3% and a solid pension scheme.
• A training program in which you and your supervisors will make a plan for additional suitable education and supervision.
• As a PhD candidate you will be enrolled in the Twente Graduate School.
• We encourage a high degree of responsibility and independence, but also stimulate interaction and discussion with colleagues.

IMS is a research group devoted to thin film growth studies, (nano)structuring techniques, and properties of complex materials, in particular oxides. It includes materials with diverse properties, like ferroelectrics, ferromagnetics and multiferroics, piezo's, high-K dielectrics, transparent conducting oxides, non-linear optical materials, ion conductors, superconducting and related materials, and anti-reflection coatings. Its research field is focussed on thin films with modified properties by doping or by artificial layered structures and superstructures. Applications are found in, e.g., nano-electronics and spintronics, optical systems, fuel and solar cells, fluidics, bio-nano sensors.