Synergism in binary nanocrystal superlattices leads to enhanced p-type conductivity in self-assembled PbTe/Ag2Te thin films
Source abstract
Abstract
The ordered cocrystallization of nanoparticles into binary superlattices enables close contact of nanocrystals with distinct physical properties, providing a route to 'metamaterials' design. Here we present the first electronic measurements of multicomponent nanocrystal solids composed of PbTe and Ag(2)Te, demonstrating synergistic effects leading to enhanced p-type conductivity. First, syntheses of size-tuneable PbTe and Ag(2)Te nanocrystals are presented, along with deposition as thin-film nanocrystal solids, whose electronic transport properties are characterized. Next, assembly of PbTe and Ag(2)Te nanocrystals into AB binary nanocrystal superlattices is demonstrated. Furthermore, binary composites of varying PbTe-Ag(2)Te stoichiometry (1:1 and 5:1) are prepared and electronically characterized. These composites show strongly enhanced (conductance approximately 100-fold increased in 1:1 composites over the sum of individual conductances of single-component PbTe and Ag(2)Te films) p-type electronic conductivity. This observation, consistent with the role of Ag(2)Te as a p-type dopant in bulk PbTe, demonstrates that nanocrystals can behave as dopants in nanostructured assemblies.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Quantum Dots Synthesis And Properties · Advanced Thermoelectric Materials and Devices · Chalcogenide Semiconductor Thin Films
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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