Synergistic Photon Management and Strain-Induced Band Gap Engineering of Two-Dimensional MoS Using Semimetal Composite Nanostructures.

2D MoS attracts increasing attention for its application in flexible electronics and photonic devices. For 2D material optoelectronic devices, the light absorption of the molecularly thin 2D absorber would be one of the key limiting factors in device efficiency, and conventional photon management techniques are not necessarily compatible with them. In this study, we show two semimetal composite nanostructures deposited on 2D MoS for synergistic photon management and strain-induced band gap engineering: (1) the pseudo-periodic Sn nanodots, (2) the conductive SnO ( < 1) core-shell nanoneedle structures.

Color Contrast of Single-Layer Graphene under White Light Illumination Induced by Broadband Photon Management.

Visualizing and manipulating the optical contrast of single-layer graphene (SLG) and other 2D materials has continuously been an interesting topic to understand fundamental light-matter interaction down to atomic thickness. Because the optical properties of SLG can be tuned by gating, demonstrating and manipulating the color contrast of SLG also has significant potential applications in ultrathin flexible color display. However, previous demonstrations of optical contrast of SLG are mostly limited to reflection intensity contrast under monochromatic illumination using the interference effect.

Tunable Buckled Beams with Mesoporous PVDF-TrFE/SWCNT Composite Film for Energy Harvesting.

By incorporating mesoporous piezoelectric materials and tuning mechanical boundary conditions a simple beam structure can significantly take advantage of limited mechanical displacements for energy harvesting. Specifically, we employed a mesoporous PVDF-TrFE composite thin film mixed with single-wall carbon nanotubes to improve the formation of the crystalline phase in this piezoelectric polymer. The film was then patterned on a thin buckled beam to form a compact energy harvester, which was used to study the effects of two boundary conditions, including the end rotation angle and the location of a mechanical stop along the beam.