2D layer of phosphorus pentamers reveals semiconductor properties on silver floor

Phosphorus is an important part of each organism and performs a key function, for instance, in vitality switch within the physique and inside cell membranes, bones and tooth. Phosphorus can be particular as a result of it happens in quite a few totally different varieties (allotropes). For instance, there may be the extremely explosive, poisonous white phosphorus, the extra steady purple phosphorus recognized from match heads, or the crystalline, semi-conducting black phosphorus. The latter has quite a few functions in digital units.

The number of phosphorus compounds and their bodily and chemical properties might be additional prolonged by the self-assembly of two-dimensional phosphorus constructions on surfaces.

Numerous two-dimensional layers

Researchers from a bunch led by Professor Ernst Meyer on the Division of Physics and the Swiss Nanoscience Institute on the College of Basel have now produced numerous two-dimensional phosphorus constructions on silver surfaces by evaporating phosphorus atoms. The work is printed within the journal Nature Communications.

Along with chains and hexagonal rings, additionally they produced planar rings of 5 phosphorus atoms (phosphorus pentamers), every of which behaves like an anion, i.e., is negatively charged.

To be able to assess whether or not such 2D layers consisting of phosphorus pentamers are appropriate for functions in nanoelectronics and nanooptics, it’s essential to characterize the properties of the atomic layer and examine the interactions with the metallic floor.

Significant knowledge via a mixture of strategies

Utilizing a mixture of atomic drive and scanning tunneling spectroscopy at low temperatures of 4 kelvin (-269.15°C), the researchers discovered that the phosphorus pentamers retain their semiconducting properties on the silver floor.

“This distinguishes the phosphorus layer from a hexagonal graphene layer, for instance, which is metallic when in direct contact with a metallic floor,” explains Dr. Rémy Pawlak, who supervised the experiments.

The phosphorus pentamer layer causes electrons to go from the steel into the phosphorus layer and a particular boundary layer, often called a p-type semiconductor-metal Schottky junction, is shaped.

“The formation of a Schottky junction on the interface may allow functions in field-effect transistors, in photo voltaic cells or as diodes,” provides Professor Ernst Meyer.

The outcomes have been confirmed by simulations carried out by analysis teams from Shenzhen and Shanghai in China.