Conjugated polymers (CPs) can potentially provide an alternative to conventional fluorescent microsphere technologies; however, examples of CP microspheres encompassing an extensive range of sizes are few, and wide‐ranging spectral control, as needed for many applications, has never been demonstrated. Blended CP microspheres consisting of individual polymers are synthesized here. They are blended to have widely separated Commission Internationale de l'Éclairage (CIE) color coordinates and a compatible synthesis while at the same time forming well‐defined domain structures. By developing appropriate mixtures of selected blue, green, and red fluorescent CPs, blended CP microspheres are demonstrated to cover an extensive range of color coordinates including white. It is shown that multi‐CP microspheres with core–shell or related structures can provide optimum characteristics, while energy and/or charge transfer in finer mixtures result in microspheres without the desired emission properties. Pre‐ or postprocessing further directs consistent changes in the CP microspheres that ultimately regulate the overall spectral response. This approach can lead to a new class of bright fluorescent microparticles with applications in a wide range of disciplines that demand maximum brightness and highly specific emission spectra.

We investigate the two-photon fluorescence (TPF) of conjugated polymer (CP) microspheres with diameters up to tens of micrometers. Two polymers, emitting in either the violet or red, were first synthesized and characterized in terms of their one-photon fluorescence and three-dimensional internal microstructure. Under femtosecond infrared excitation, both types of microspheres showed a strong TPF, which was investigated by the excitation intensity dependence, emission spectroscopy, time-resolved luminescence, and photobleaching dynamics. While the violet-fluorescent microspheres performed similarly compared to dye-doped polystyrene counterparts emitting at a similar wavelength, the red-fluorescent microspheres showed a two-orders-of-magnitude stronger TPF. This excellent performance is attributed to enhanced hyperpolarizability associated with intermolecular interactions in the polymer solid, indicating a route toward designed CP microspheres that could outperform currently-available microparticles for sensing or imaging applications involving two-photon fluorescence.

This work synthesizes a green‐fluorescent conjugated polymer and performs basic photophysical characterization of this new material. Atums Green[1] is synthesized by a Suzuki cross‐coupling polymerization reaction between isostructural dibromo and diboronic acid monomers and is structurally characterized by nuclear magnetic resonance and gel permeation chromatography. The polymer consists of an alkoxy‐substituted 1,4‐bis((E)‐styryl)benzene repeating unit with molecular weight up to Mn = 50 kDa relative to polystyrene. Atums Green shows a strong green fluorescence maximized at ≈500 nm in chloroform and tetrahydrofuran solutions, with an absolute quantum efficiency as high as 98%. The photobleaching dynamics and time‐resolved photoluminescence (TRPL) are measured both in solutions and in solid films. Finally, solution‐based lasing is demonstrated in a bulk lasing cavity and in a cylindrical microcavity. Lasing emission is readily achieved in both formats, indicating that Atums Green has excellent emission characteristics, and further suggesting that it may present a viable green‐emitting conjugated polymer materials system for light emission applications.

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In the present study, the structural and electrical properties of carbon nanoparticles, prepared from kerosene has been investigated with the help of Thermogravimetric Analysis (TGA), Atomic Force Microscope (AFM) and Ecopia Hall-effect measurement system. The spherical carbon particles size was observed with the help of Atomic Force Microscope (AFM) and the size found 80 nm in diameter as an aggregated particles. The electrical parameters such as resistivity, conductivity, magneto-resistance, mobility, and average Hall coefficient were measured by Ecopia Hall effect measurement system by four-point probe method at a suitable condition. TheI-Vcharacteristic curve of Carbon Nanoparticle Thin Film (CNTF) was observed by a source-meter and a current rectifying behavior at the Ag/CNTF interface was found.The CNPs synthesized from kerosene was found as anntype semiconductor and other electrical properties were compared with CNPs prepared from diesel in the previous study.