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Conventional upconversion thermometry strategy, based on the thermally coupled levels (TCL) of lanthanide ions, confronts a dilemma in simultaneously achieving high absolute/relative temperature (T) sensitivities (Sa and Sr) and good signal discriminability. Herein, a novel thermometry strategy by utilizing the synergistic effect of dual-wavelength lasers to manipulate electron thermal distribution is proposed to go beyond the limitation of the TCL-based strategy. In the case of NaGdF4: 20%Yb3+, 2%Er3+ nanoparticles upon 980 & 1530 nm dual-excitation, it is found that more efficient utilization of excited photons results in a higher electron concentration in ladder-like energy levels of Er3+, owing to the diverse pumping routes, which increases transition rate of the T-dependent phonon-assisted cross-relaxation process, and in turn establishes a thermally-sensitive electronic connection between Er3+: 2H11/2,4S3/2 and Er3+: 4F9/2. Remarkably, not only a highest record value of Sa (0.0365 K−1) for the Er3+ doped host materials in the physiological temperature range (303–343 K) is achieved, but also a high Sr (1.29% K-1) and an excellent signal discriminability (Δλ = 112 nm) are obtained. Combining a much intensified upconversion (UC) signal and a good size/shape homogeneity in nanometer scale, the investigated NaGdF4: 20%Yb3+, 2%Er3+ upon dual-wavelength excitation is potentially applicable in the intracellular thermal sensing and imaging. This work exploits an effective way to develop high-performance T-sensors, and the proposed thermometry strategy can be extended to surges of the other lanthanide ions doped systems pumped by multiple-wavelength lasers.

The strong demands for “high-power” w-LEDs stimulate development of the all-inorganic glass ceramic (GC) phosphors with admirable thermal/chemical reliabilities. Herein, an ultra-low melting Sn-P-F-O glass was successfully prepared, demonstrating as an appropriate host to accommodate yellow YAG:Ce3+ and red CASN:Eu2+ without degrading their original luminescent properties. The yellow and red GCs yield QE as high as 92.0% and 88.6%, respectively. Moreover, they exhibit excellent resistance to thermal quenching, i.e., only 9.5% and 3.0% decreases in luminescence intensity at 150 °C compared with that at room temperature. Remarkably, LED using the YAG:Ce3+/CASN:Eu2+ co-sintered GC as color converter yields bright warm white light with CCT of 3554 K, under 350 mA current, highlighting a new record in LE of 90.71 lm/W among the GC-based warm w-LEDs. Accelerated experiments demonstrate the presently studied GC also exhibits a superior thermal stability, therefore is capable for operating at high power condition for a long time.

In this paper, Fe3O4/Ag/RGO reusable ternary nanocomposites are explored via a facile one-pot solvothermal strategies, and the catalytic performance and antibacterial activity are investigated in detail. The catalytic performance of Fe3O4/Ag/RGO towards the reduction of 4-NP into 4-AP is evaluated, and the reaction rate constant (k) for Fe3O4/Ag/RGO is calculated to be 0.03086 s−1, which is higher than that of Fe3O4/Ag (0.01756 s−1), indicating the catalytic activity is improved after decorating Fe3O4/Ag onto the graphene sheet. The antibacterial experiment shows Fe3O4/Ag/RGO ternary nanocomposites present a wide range of antibacterial activities against Gram-positive bacteria (S. aureus and B. cereus) and Gram-negative bacteria (E. coli and P. aeruginosa). The minimal inhibitory concentrations (MIC) for Fe3O4/Ag/RGO nanocomposites against four bacterial species are determined. Additionally, Fe3O4/Ag/RGO nanocomposites also present high reusability as catalyst and antibacterial agent. The results illustrated in this paper imply that the multifunctional performances such as efficient reduction of 4-NP followed by superior anti-reproduction of pathogenic bacteria make the Fe3O4/Ag/RGO ternary nanocomposites a promising catalyst for dye-polluted water and disinfectant agent for wastewater treatment and purification.

S-doped porous carbon (S/C) has been successfully fabricated from biomass waste (drug residue). The S/C not only has a unique porous structure and channel, but porous structures are interconnected to form a sponge-like structures. The unique structure not only increases the specific surface area and energy storage sites, but also shortens the path of ion transmission and charge transfer. When S/C-1 is used as lithium ion batteries (LIBs) anode, the capacity of 710 mAh g−1 can be achieved after 50 cycles at 0.1 A g−1. The capacity still has 364 mAh g−1 at 5 A g−1 for long-life-cycle. For sodium ion batteries (SIBs), a capacity of 518 mAh g−1 can be delivered at 0.1 A g−1 for 50 cycles, and a capacity of long-life-cycle at 5 A g−1 still maintains 230 mAh g−1. The improving rate capacities of S/C-1 can be attributed to the short diffusion lengths of Li+ and Na+ ions for uniform sponge-like structure, large specific surface area (SSA) and additional active sites. This work has an important opportunity to change the current energy situation.

Selenium has been successfully doped into graphite phase carbon nitride (g-C 3 N 4 ) by a simple thermal condensation method through calcinating the mixture of dicyandiamide, cyanuric acid and selenium dioxide. The morphology and composition of thus-prepared selenium doped graphite phase carbon nitride (Se-g-C 3 N 4 ) nanosheets were characterized by transmission electron microscopy (TEM), high resolution TEM, X-ray diffraction (XRD), fourier transform infrared (FT-IR) spectra and X-ray photoelectron spectroscopy (XPS). Characterization results revealed that the resultant products have typical ultrathin lamellar structure with the uniform lateral diameter of 20 nm. The amount of Se dopant is ca. 2.1 at% based on the XPS result. For the first time, ultrathin Se-g-C 3 N 4 nanosheets have been demonstrated to possess an intrinsic peroxidase activity by following the Michaelis–Menten kinetics and even have higher affinity to peroxidase substrates TMB and H 2 O 2 in comparison to that of HRP. Se-g-C 3 N 4 nanosheets is conducive to mediating electron transfer and thus to enhancing the catalytic oxidation of the substrate TMB in the presence of H 2 O 2 to produce a blue color change in aqueous solution. More importantly, a sensitive and selective method for xanthine detection was developed using xanthine oxidase and the as-prepared Se-g-C 3 N 4 nanosheets. On the basis of the high catalytic activity of Se-g-C 3 N 4 nanosheets, a rapid, sensitive, and convenient approach was developed for colorimetric detection of xanthine with detection limit 1.6 × 10 −8 mol L −1 . Taking the advantages of this, the novel Se-g-C 3 N 4 nanosheets represent a promising candidate as an enzyme mimic and may find a wide range of new applications in diagnostics and biotechnology fields.

Hydrogenation of CO 2 is challenging from both economic and environmental view points. In the present study, density functional theory (DFT) method was employed to investigate the reaction mechanism of methanol synthesis from CO 2 hydrogenation. Two possible reaction pathways were proposed, where hydrogenation of CO 2 led to intermediate HOCO free radical, followed by the formation of intermediate HCOOH or CO, finally resulting in the methanol formation. The results showed that the preferred pathway was CO 2 → CO → H 2 CO → CH 3 OH, whose enthalpy energy is −35.389788 kJ/mol. The calculated results of the configuration and the enthalpy energy of classic molecules were in good agreement with the values in literature, which indicated that the results should be reliable.

In this work, electrophoretic deposition (EPD) technique was employed for fabricating the barium titanate (BaTiO 3 ) films on the Si substrate modified with the ordered conducting polyaniline (PANI) layers. Firstly, surface polymerization of ordered conducting PANI layers on the Si substrate modified with the aniline-bearing silane self-assembled monolayer was performed by polymerization of aniline monomer in an acidic aqueous solution. Then, EPD of BaTiO 3 films was fulfilled using the conducting PANI layers coated Si wafer as the cathode. The analytical results demonstrate that the crack-free, relatively dense and smooth BaTiO 3 films have been accomplished on the PANI layers modified Si substrate with the appropriate suspension concentration and the deposited film thickness can be changed expediently by adjusting EPD process parameters. This method provides a potential route for fabricating ceramic films on the non-conductive Si or glass substrates using EPD technique.