2D boundaries could create electricity

Science Daily  August 16, 2022 The presence of piezoelectricity in 2D materials often depends on the number of layers. A team of researchers in the US (Rice University, UCLA, University of Houston, AF Laboratory Wright Patterson FB, Pennsylvania State University) made a one-dimensional, metal-semiconductor junction in a 2D heterostructure. A less than 10 nanometers thick junction was formed when tellurium gas was introduced while molybdenum metal formed a film on silicon dioxide in a chemical vapor deposition furnace. The process created islands of semiconducting molybdenum telluride phases in the sea of metallic phases. Applying voltage to the junction via the […]

Ultrahigh piezoelectric performance demonstrated in ceramic materials

Phys.org  May 18, 2022 A team of researchers in the US (Pennsylvania State University, Michigan Technological University) developed and demonstrated a mechanism that enhances the magnitude of the piezoelectric coefficient of a ceramic. Through extensive characterization conducted using high-resolution microscopy and diffraction techniques in conjunction with the computational models they found that chemical heterogeneity and anisotropy are the underlying mechanisms that govern the piezoelectric performance of ceramic materials. They showed that by aligning all the grains in a ceramic material along certain crystallographic axes they could get a very high piezoelectric response. They achieved close to 2,000 picocoulombs per Newton. […]