Compositional grading has been widely exploited in highly efficient Cu(In,Ga)Se2, CdTe, GaAs, quantum dot solar cells, and this strategy has the potential to improve the performance of emerging perovskite solar cells. However, realizing and maintaining compositionally graded perovskite absorber from solution processing is challenging. Moreover, the operational stability of graded perovskite sol...

A non-linear thermodynamic analysis of ferroelectric systems with localized space charges for monolithic and compositionally graded materials is described wherein the electrostatic interlayer interactions are specifically accounted for. The electrostatic coupling is established through the built-in polarization due to the space charges and the intrinsic polarization variations between the ferro...

Joining of dissimilar metals is required for numerous applications in industries such as chemical, energy and automotive. It challenging due to differences melting point, density, thermal expansion the being joined. Common welding techniques involve limiting solidification a narrow area leading high stresses potentially brittle intermetallic phases. Furthermore, geometric complexity these welde...

Recently, there has been significant interest toward the development of tunable dielectric materials for voltage-controlled, frequency-agile phase shifters and filters operating in the microwave regime. The fundamental challenge in designing materials systems for such tunable devices is the simultaneous requirement of high dielectric tunability ([40%) over a large temperature interval (-10 C to...

The current work provides an overview of the state-of-the-art in polymer and metal additive manufacturing and provides a progress report on the science and technology behind gradient metal alloys produced through laser deposition. The research discusses a road map for creating gradient metals using additive manufacturing, demonstrates basic science results obtainable through the methodology, sh...

Laser surface melting has been applied to near eutectic NiO-YSZ sintered ceramics. The objective is to generate a functional gradient composite material with graded microstructure and composition. At low solidification rates the resultant material has a graded composition, with a severe NiO segregation towards the surface. A thick NiO layer whose thickness depends on the travelling speed is for...

Abstract Background Soft, biological, and bio-inspired materials are often compositionally heterogeneous structurally anisotropic, they frequently feature graded or layered organizations. This design complexity enables exceptional ranges in properties performance yet complicates a fundamental understanding of the contact mechanics. Recent studies soft gel layers have relied on Hertzian Winkler ...