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CDs are applied in the enhancement of EL of Poly (9-vinyl carbazole) with the increased brightness by 54.3 %. [Display omitted] • CDs are applied in the enhancement of EL of PVK with increased brightness by 54.3 %. • The CDs enhanced PVK LEDs possess the EL wavelength of 432 nm. • The CIE coordinates of CDs enhanced PVK LEDs are at (0.17, 0.10) with the brightness of 176 cd m−2. • The mechanisms of charge transport between CDs and PVK are determined by TPV and method of EMD. Carbon dots (CDs) are one species of multifunctionally auxiliary materials with promising application in photoelectrocatalyst and photoelectrodevices. However, there are few reports on enhancing the electroluminescence (EL) of materials by CDs and the effects of CDs on the charge transport dynamics have not been revealed so far. Herein, CDs are firstly successful to be applied in the enhancement of EL of Poly (9-vinyl carbazole), which is set as model material for research, abbreviated as PVK with the EL wavelength of 432 nm. The brightness of CDs enhanced PVK LEDs reaches 176 cd m−2 that obviously 54.3 % higher than that of pure PVK based LEDs and other parameters are all improved. The Commission Internationale d'Eclairage coordinates of CDs enhanced PVK LEDs are situated at (0.17, 0.10). Notably, through the transient photovoltage technology and method of empirical mode decomposition, the mechanisms of charge transport dynamics between CDs and PVK molecules are determined. This work paves a new direction for the improvement of the luminescent properties of electroluminescent devices and a new mentality to understand the effects of CDs on charge transport in the EL process. [ABSTRACT FROM AUTHOR]

This paper presents controllable growth and photocatalytic activity of TiO 2 hierarchical nanostructures by solvothermal method at different temperatures. It is revealed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) that the morphology of TiO 2 can be effectively controlled as rose-like, chrysanthemum-like and sea-urchin-like only changing solvothermal temperature. BET surface area analysis confirms the presence of a mesoporous network in all the nanostructures, and shows high surface area at relatively high temperature. The photocatalytic activities of the photocatalysts are evaluated by the photodegradation of RhB under UV light irradiation. The TiO 2 samples exhibit high activity on the photodegradation of RhB, which is higher than that of the commercial P25. The enhancement in photocatalytic performance can be attributed to the synergetic effect of the surface area, crystallinity, band gap and crystalline size. [ABSTRACT FROM AUTHOR]

• Ultralight PAFP/GONRs-A aerogel was prepared facilely by solvothermal polymerization method. • The aerogel showed a low density, large specific surface area and high phosphorus content. • The aerogel presented an unexpectedly high adsorption capacity and selectivity for thorium. • Phosphonic groups play an important role in Th(IV) adsorption. • DFT calculations revealed the coordination modes of Th(IV) with the aerogel, confirming the experimental results. An ultralight three-dimensional porous network phosphonic acid functionalized polymer/graphene oxide nanoribbons aerogel (PAFP/GONRs-A) was prepared using trimethylolpropane trimethacrylate (TRIM) and vinylphosphonic acid (VPA) as monomers via solvothermal polymerization method for thorium capture from aqueous solutions. The synthesized aerogel presented a low density (10.6 mg cm−3), large specific surface area (433.2 m2 g−1) and high phosphorus content (18.2%). The adsorption process of Th(IV) on PAFP/GONRs-A was pH-dependent, spontaneous and endothermic, and well described by the pseudo-second-order kinetic and Langmuir isotherm model. Under optimal experimental conditions (10 mg of adsorbent dosage, 50 mL of solution volume, 240 min of contact time, 298 K of temperature), PAFP/GONRs-A presented an excellent high adsorption capacity of thorium, with maximum capacity of 457.9 mg g−1 at a pH of 3.0, and maximum thorium-selectivity of 87.1% at a pH of 2.0. The values of ΔG for Th(IV) adsorption on PAFP/GONRs-A were calculated to be −21.78, –23.32, −24.87 and −26.41 kJ mol−1 at 283, 298, 313 and 328 K, respectively. Density functional theory (DFT) calculations and X-ray photoelectron spectroscopy (XPS) revealed that Th(IV) ions were fixed in aerogel by coordinating with the P = O groups of PAFP/GONRs-A, and both 1:2 ratio of Th(IV) with the P = O ligands on the same graft chain and 1:4 ratio of Th(IV) with P = O ligands on two distinct graft chains could jointly contribute to the adsorption of Th(IV) on PAFP/GONRs-A. This work offers a facile approach for synthesizing the phosphonic acid functionalized graphene oxide nanoribbons aerogel and demonstrates that PAFP/GONRs-A has high potential as a candidate adsorbent for the capture of thorium from aqueous solution. [ABSTRACT FROM AUTHOR]