pnp-switchable Materials as Diodes and Transistors (pnp-mat)

• Applicants: Professor Dr. Alexander Walter Holleitner; Professor Dr. Tom Nilges
• Subject Area: Solid State and Surface Chemistry, Material Synthesis ; Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 522732992

This projects deals with the first realization and fabrication of one-component diodes and one-component transistors which are planned to be utilized in light, gas and water splitting applications afterwards. We intend to synthesise and use pnp-switchable semiconductors like Ag18Cu3Te11Cl3 und AgCuS which show a reversible structural phase transition and an unique pnp switch of their semiconductor mechanism at this point. Goal of this project is to utilize this effect to create the first and former unseen one-component diode and one-component transistor which do not consist of two independent p- and n-type doped semiconductors, but which are generated by a simple thermal activation in a single material instead. Using U/I measurements on bulk and nano-materials we intend to determine the physical properties, the pn-transition kinetics and the electrical parameters of the diodes and transistors. Beside the known phases we will seek for new pnp-switchable materials and we intend to optimize the afore mentioned ones by substitution of cations and anions. Selected compounds will be tested for their potential in gas and light sensing applications and for water splitting. Here fore, we will measure the U/I characteristics upon application of gas or light or we test these materials as water splitting catalyst upon switching. Especially Ag18Cu3Te11Cl3 has an extraordinary potential with its pnp-switch at room temperature to be used in various applications. Recently, we were able to substantiate and publish the diode behaviour of Ag18Cu3Te11Cl3. The project is planned in close collaboration between two groups with competences in chemical material synthesis, nano chemistry, and crystal physics. After the termination of the project one-component diodes and transistors may be new players in IT technology, as sensors, or in manifold catalytic applications.

• DFG Programme: Research Grants
• International Connection: USA
• Cooperation Partner: Professor Dr. Chongwu Zhou