Highly stable two-dimensional Ruddlesden-Popper perovskite-based resistive switching memory devices.

Resistive switching random-access memory (ReRAM) devices based on organic-inorganic halide perovskites (OIHPs) have emerged as a new class of data storage devices. Recently, two-dimensional (2D) OIHPs have attracted much attention for ReRAM applications because of their structural diversity and superior stability. Here, the RS characteristics of ReRAM devices fabricated utilizing pure 2D Ruddlesden-Popper (RP) perovskite crystals, namely (TEA)PbBr and (TEA)PbI, are reported.

Efficient Multiple Exciton Generation in Monolayer MoS.

Utilization of the excess energy of photoexcitation that is otherwise lost as thermal effects can improve the efficiency of next-generation light-harvesting devices. Multiple exciton generation (MEG) in semiconducting materials yields two or more excitons by absorbing a single high-energy photon, which can break the Shockley-Queisser limit for the conversion efficiency of photovoltaic devices. Recently, monolayer transition metal dichalcogenides (TMDs) have emerged as promising light-harvesting materials because of their high absorption coefficient.

Through structural isomerism: positional effect of alkyne functionality on molecular optical properties.

Literature studies on the effects of alkyne functionality in manipulating the optical properties of donor-π-acceptor-type molecular scaffolds have been scarce compared to those on the alkene functional group. Here, two structurally isomeric donor-acceptor (D-A) dyes were synthesized to study the positional effect of alkyne functionality (triple bond) on their optical, electrochemical and charge generation properties in order to design efficient dyes for possible application in dye sensitized solar cells (DSSCs). These dyes, named CAPC and PACC, contain carbazole and cyanoacrylic acid as the donor and acceptor units, respectively, and the π-conjugation length within the molecules was controlled by the introduction of an alkyne group.

Nonlinear Optical Properties of CdSe Quantum Dots Having Different Sizes.

We synthesis different sizes of cadmium selenide quantum dots (CdSe QDs) and their linear and nonlinear optical properties. Size-controlled CdSe QDs are characterized by ultraviolet-visible absorption, photoluminescence, transmission electron microscope (TEM), and Z-scan techniques. Redshift was observed in the linear absorption and photoluminescence with an increase in the size of CdSe QDs.