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Abstract Titanium doping on LiNi 1/3 Co 1/3 Mn 1/3 O 2 cathode material is performed in a bid to improve its electrochemical and thermal properties at high voltage. The particle hardness is measured in order to verify the structural stability, and is found to improve from 104 to 143 MPa as a result of the Ti doping. Thus, high electrode density is obtained with less cracked particles in the electrode. Electrode density of 3.9 g cm−3 is employed in order to confirm the effect of particle hardness on the electrochemical performance. The cycle performance is evaluated at 4.5 V and high temperature of 60 °C, and the obtained capacity retention after 50 cycles is found to be significantly improved via Ti doping. The cycled electrodes show that the generation of crack inside particles are suppressed for Ti-doped LiNi 1/3 Co 1/3 Mn 1/3 O 2. The thermal stability of the charged electrode is also improved via Ti doping, because of the enhanced structural stability. On the basis of these results, Ti is considered to be a viable dopant for improving particle hardness, which is an important factor as regards improving the electrochemical and thermal properties of LiNi 1/3 Co 1/3 Mn 1/3 O 2. Highlights • Ti doped LiNi 1/3 Co 1/3 Mn 1/3 O 2 was successfully synthesized via a co-precipitation method. • Particle hardness of LiNi 1/3 Co 1/3 Mn 1/3 O 2 is greatly improved thorough Ti doping. • Cycle performance at high voltage and high temperature is greatly improved by Ti doping. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single atom Co-anchored nitrogen‑doped graphene was developed for PMS activation. • 1O 2 generation was boosted in PMS activation and dominant for pollutant degradation. • The acute toxicity of pollutants was effectively reduced in PMS activation. • Developed catalyst exhibited remarkable cycling stability and negligible leaching. Singlet oxygen (1O 2) is an excellent active species generated in advanced oxidation processes (AOPs) that exhibits high selectivity, long life and wide pH tolerance. Therefore, catalysts for highly efficient and selective generation of 1O 2 in AOPs would be highly desirable. This study developed a single atom Co-anchored nitrogen‑doped graphene (Co SAC -NG), which showed excellent catalytic performance for peroxymonosulfate (PMS) activation and bisphenol A degradation, with the pseudofirst-order reaction rate constant improved from 8.13 × 10−4 min−1 without catalyst to 4.42 × 10−2 min−1 with 5 mg L−1 Co SAC -NG. Mechanism studies indicated that Co SAC -NG selectively enhanced 1O 2 generation, which was the dominant active specie for pollutant degradation. Moreover, the Co SAC -NG/PMS system effectively reduced the acute toxicity of pollutant, and Co SAC -NG exhibited remarkable cycling stability and negligible leaching. This study develops a new catalyst with high selectivity for 1O 2 generation and provides a reference for application of single atom catalyst in PMS-based AOPs. [ABSTRACT FROM AUTHOR]

White light-emitting diodes have been intensively explored as a technique of green energy-conversion in recent decades. In this work, a unique Tb3+/Sm3+ co-doped P 2 O 5 –Gd 2 O 3 –Ga 2 O 3 –NaF–ZnO glass consisting of Q 0, Q 1 and Q 2 units was successfully synthesized. The DSC curves demonstrated that the glass stability gradually deteriorated with the increase of Sm3+ contents. The emission spectra exhibited the energy transfer from Dy3+ to Tb3+ ions, and the energy transfer efficiency and probability grew monotonously with the increase of Sm3+ contents. With the help of temperature-dependent emission spectra, the glasses were validated to be thermally stable. The fluorescence curves and Inokuti-Hirayama model demonstrated that the dominant mechanism in the energy transfer process was electric dipole-quadrupole interaction. In addition. the white-light emission with suitable chromaticity coordinates and CCTs could be obtained by adjusting the contents of the sensitizer and activator for PGGNZ glasses. All investigations revealed the potential application of Tb3+/Sm3+ co-doped glasses in optical device applications. • A novel Tb3+/Sm3+-doped phosphate glass for white light emission has been prepared. • The glass has high thermal stability (84.1% of the initial intensity at 150 °C). • Energy transfer via dipole-dipole interaction leads to concentration quenching. • This glass has tunable CCT, fluorescence lifetimes, and chromaticity coordinates. • These glasses have potential applications in display devices and W-LED lighting. [ABSTRACT FROM AUTHOR]

In this paper, we report a facile method to prepare lanthanide-doped Na 3 ZrF 7 upconversion nanoparticles. By using this technique, monodisperse lanthanide-doped Na 3 ZrF 7 nanoparticles of approximately 10 nm in diameter could be synthesized at 260 °C. The Na 3 ZrF 7 :Yb 3+ 20%, Er 3+ 2%, and Na 3 ZrF 7 :Yb 3+ 20%, Tm 3+ 1% nanoparticles exhibited almost pure red and near-infrared emissions, respectively; however, the Na 3 ZrF 7 :Yb 3+ 20%, Ho 3+ 2% nanoparticles exhibited a multiband emission. The special emission output was caused by the cross relaxation of the activator ions, as a rare-earth ion (RE 3+ ) cluster was formed, shortening the distance between the RE 3+ ions. The emission output of the Na 3 ZrF 7 :Yb 3+ 20%, Er 3+ 2% nanoparticles was significantly influenced by the NaOH dosage. The Na 3 ZrF 7 :Yb 3+ 20%, Er 3+ 2% nanoparticles synthesized with a different NaOH dosage of 2.5 mmol showed the most intense total emission intensity among all samples. However, the red/green emission ratio was gradually enhanced as the NaOH dosage increased. [ABSTRACT FROM AUTHOR]

TiO 2 nanocrystallites with titanium (IV) fluoride treatment were fabricated and studied as dye sensitized solar cells photoanode. F doping into pre-existing mesoporous TiO 2 is achieved by a simple hydrolysis method. Overall photo-to-current conversion-efficiency of the device could be enhanced up to 23% due to the increase of photocurrent density, fill factor and open-circuit voltage, compared with undoped TiO 2 . From electrochemical impedance measurements, we deduce that the presence of F dopants enhances cell performance by improving the charge transport and retarding the recombination process in the photoanode. [ABSTRACT FROM AUTHOR]

[Display omitted] • Conjugated polyelectrolyte was developed and used as a dopant in PSCs. • PPNNA doping improves the formation of the perovskite film. • PPNNA doping realizes efficient surface passivation and electron extraction. • PPNNA can significantly enhance device performance and stability. Perovskite solar cells (PSCs) have achieved great success in the past few years because of outstanding photovoltaic performance. However, the existence of electronic trap states in the perovskite film is an obstacle for the fabrication of high-performance and stable PSCs. Herein, a linear conjugated polyelectrolyte was developed and employed as a dopant to improve the performance and stability of the perovskite film. The PPNNA doping can passivate surface defects to reduce the electronic trap states in the perovskite film, while simultaneously enhancing the electron extraction and transport to achieve high-efficiency solar cells. Furthermore, the PPNNA-doped perovskite film shows better stability from efficient surface passivation. The optimal 0.4% PPNNA-doped device exhibits better photovoltaic efficiency (20.38%) with enhanced device stability as compared to the control device (18.51%). This novel method by doping with the conjugated polyelectrolyte provides a pathway to fabricate high-efficiency and stable inverted PSCs. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen peroxide (H 2 O 2) by oxygen and phosphorus co-doped graphitic carbon nitride (C 3 N 4) with cobalt phosphate (CoP) cocatalyst is investigated. The photocatalyst powder of CoP-C 3 N 4 1:n, n = 0–4, n is the weight ratio of cyanuric acid added) was synthesized by melamine cyanurate template method. Characterization of the catalyst was performed by X-ray diffraction analysis, and scanning electron microscopy, X-ray photoemission spectra, and fluorescence decay spectra. Oxygen doping was performed by the melamine and cyanuric acid template method, followed by phosphorus doping of the C 3 N 4 backbone by the introduction of CoP. Co-doping of O and P atom facilitated charge transfer on the C 3 N 4 backbone, while CoP facilitated charge separation at the C 3 N 4 interface. The CoP-C 3 N 4 (1:4) photocatalyst increased H 2 O 2 production rate by 293 % compared to that of the cyanuric acid-free photocatalyst and also achieved the photocatalytic oxygen evolution from water. These results indicate that O,P co-doped CoP-C 3 N 4 can perform sacrificial agent-free hydrogen peroxide under visible light irradiation. [Display omitted] • O,P-co-doped CoP-C 3 N 4 increased H 2 O 2 production is investigated first time. • The addition of cyanuric acid promoted the doping of phosphorus into C 3 N 4 structure. • Hydrogen peroxide synthesis under sacrificial agent-free and visible light. • The O,P-co-doped CoP-C 3 N 4 increased H 2 O 2 production rate as high as 293 %. [ABSTRACT FROM AUTHOR]

This paper aims to provide an insight into the effects of different doping ratios on the crystal structure, thermal conductivity, ion diffusion, and high-temperature thermal expansion coefficient of Sc 2 O 3 -Gd 2 O 3 -Y 2 O 3 co-doped ZrO 2 (ScGdYSZ) materials. They were investigated by a non-equilibrium molecular dynamics method. The results show that with Gd 2 O 3 -Sc 2 O 3 -Y 2 O 3 co-doping, the thermal expansion of the resulting materials is all relatively close to that of 8YSZ materials and linear with temperature. At 1473 K, 1 mol%Sc 2 O 3 –3 mol%Gd 2 O 3 –4 mol%Y 2 O 3 stabilized ZrO 2 (1Sc3Gd4YSZ) coating material has the smallest thermal conductivity, with a thermal conductivity of 5.66 W·(m·K)−1. The mean square displacement (MSD) of O2− was linear with the time when the sum of the doping ratio of Sc 2 O 3 and Gd 2 O 3 was 4 mol%, and the MSD of O2− in the material increased with the doping ratio of Sc 2 O 3. increases, the MSD of O2− in the material increases, and the migration diffusion rate is accelerated. • we conducted an in-depth study of the effects of different doping ratios on the microstructure and thermal transport of this material by non-equilibrium molecular dynamics simulations. • Co-doping of Gd 2 O 3 , Sc 2 O 3 , and Y 2 O 3 has no effect on the microstructure of thermal barrier coating materials, whereas doping of Gd 2 O 3 and Sc 2 O 3 weakens and strengthens the materials' stability of crystal structure, respectively. • Gd 2 O 3 , Sc 2 O 3 and Y 2 O 3 were co-doped, were co-doped, and the thermal expansion of the resulting materials was all relatively close to that of the 8YSZ material and linear with temperature. • At 1473 K, when the doping ratio of Sc 2 O 3 and Gd 2 O 3 is summed to 4 mol%, the MSD of O2− is linearly related to the system movement time, and the migration diffusion rate is accelerated as the MSD of O2− in the material increases with the larger Sc 2 O 3 doping ratio. [ABSTRACT FROM AUTHOR]

The development of highly efficient and stable anode electrocatalysts is highly demanding and challenging in seawater electrocatalysis for industrial application. Herein, we have constructed C, N co-doped mesoporous Co-based hybrid phosphates via a facile glucose-mediated regulation. The optimal C4-2-0.5Glu-550 by calcination at a mild temperature exhibits superior OER performance in 1.0 M KOH seawater with an overpotential of 296 mV at 10 mA cm−2 and a Tafel slope of 109 mV dec−1 as well as long-term stability (for at least 19 h). Combined with structural characterization, its excellent electrocatalytic performance should be attributed that the proper heteroatom doping regulates its electronic structure, correspondingly, adjusts the adsorption strength of the intermediates, in addition, its open porous structure increases exposed active sites and facilitates the electrons/mass transfer and the adsorption of reactants, above all, the carbon layer formed by the introduction of glucose significantly improves its corrosion resistance, further enhancing its performance in alkaline realistic seawater. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrosulfuric acid is an aqueous solution of hydrogen sulfide (H 2 S). At physiological pH, approximately 80% of the total amount of H 2 S exists in the form of monoanionic HS−. Because HS− is both widely distributed and highly toxic to humans, it is necessary to design an efficient method to detect HS− with high sensitivity and selectivity. So, the nitrogen-doped carbon dots (NCDs) with green fluorescence are synthesized using a one-step hydrothermal method. The as-prepared NCDs show it can be effectively used as an indicator for monitoring HS−. And the NCD fluorescence intensity exhibits a linear relationship with HS− concentration. In addition, NCDs as a probe can be applied for fluorescence imaging in living cells to detect the presence of trace exogenous HS−. [Display omitted] • NCDs with green fluorescent were synthesized hydrothermally using one step hydrothermal method. • NCDs exhibit good sensitivity and selectivity for HS−. • The detection concentration range of NCDs-based probe was 0–55 μM with a detection limit of 48.87 nM. • Low toxicity of NCDs can successfully detect intracellular HS−. [ABSTRACT FROM AUTHOR]

In this paper, K+ ion-doped Y 2 O 3 : Yb3+/Er3+ luminescent films were prepared using the sol-gel method. The structures of the films were studied using X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and Fourier transform infrared spectroscopy. A series of high-quality thin films with good crystallization were prepared. The effect of K+ ion doping on the light emission of the samples was investigated. With increasing K+ doping concentration, initially, the lattice was compressed and then stretched. For the undoped samples, the main light emission bands were green and red emissions attributed to Er3+: 2H 11/2 (4S 3/2) →4I 15/2 and Er3+: 4F 9/2 → 4I 15/2 , respectively, both of which are two-photon processes, accompanied by weak purple emission attributed to Er3+: 2G 7/2 → 4I 15/2 , which is a three-photon process. Compared with the undoped sample, the emission attributed to three-photon process may be eliminated by using K+ doping, and the green and red emission intensity may be increased by factors of 2.39 and 2.51 with increasing K+ ion doping, respectively. With the increase in K+ ion doping, the changes in active luminescent centers and distance between rare earth ions were analyzed, and the effect of the process energy transfer (ET) process and cross relaxation (CR) attributed to those on light emission was discussed. • K+ enhanced both green and red luminescence intensity notably. • K+ eliminated purple emission, retained green and red emission. • K+ reduced lattice's symmetry and changed the distance between rare earth ions. • Cross relaxation played major role in low K+ doping concentration. • Energy transfer played major role in high K+ doping concentration. [ABSTRACT FROM AUTHOR]