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A novel photocatalyst of Bi3.64Mo0.36O6.55 doped with Tm3+/Yb3+ was prepared by a simple coprecipitation method followed by a calcination technology. The as‐synthesized Tm3+/Yb3+‐Bi3.64Mo0.36O6.55 samples were characterized by various analytical methods. The as‐synthesized sample exhibited enhanced photocatalytic activity when degrading Rhodamine B under the irradiation of visible‐light. The photocatalytic degradation efficiency of Tm3+/Yb3+‐Bi3.64Mo0.36O6.55 (95.2%) was higher than that of pure Bi3.64Mo0.36O6.55 (85.2%) in 50 min. Besides, the sample revealed a stable photocatalytic property after four photodegradation cycles. Therefore, this study may provide a better method to obtain stable upconversion photocatalyst degrading organic pollution with greatly improved activity. [ABSTRACT FROM AUTHOR]

Using Cu-CoFe/Co/NC as trifunctional electrocatalysts in alkaline seawater, an overall hydrazine splitting (OHzS) unit is self-powered by a direct hydrazine fuel cell (DHzFC), demonstrating the great potential of Cu-CoFe/Co/NC as trifunctional electrocatalysts toward energy storage and conversion devices. [Display omitted] • Cu-doped CoFe/Co encapsulated by N -doped carbon (Cu-CoFe/Co/NC) is synthesized. • The electronic structure and d-band center of catalyst are regulated. • The catalyst show good ORR, HzOR and HER performance in alkaline seawater. • The catalyst is used into direct hydrazine fuel cell and overall hydrazine splitting. The development of high-performance and robust electrocatalyst suitable for oxygen reduction reaction (ORR), hydrazine oxidation reaction (HzOR), and hydrogen evolution reaction (HER) in seawater still faces huge challenges. In this study, Cu-doped CoFe/Co encapsulated by N -doped carbon (Cu-CoFe/Co/NC) is synthesized via chemical precipitation followed by carbonization method, in which the electronic structure and d-band center of Cu-CoFe/Co/NC are regulated by metal doping and hetero-engineering. The as-synthesized Cu-CoFe/Co/NC exhibit excellent electrocatalytic activity for ORR (E 1/2 = 0.87 V), HzOR (η 10 = 281 mV), and HER (η -10 = 217 mV) in alkaline seawater. Inspiringly, the self-assembled direct hydrazine fuel cell (DHzFC) are used to power overall hydrazine splitting (OHzS) for proof of concept, demonstrating the great potential of Cu-CoFe/Co/NC as trifunctional electrocatalyst toward energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

A novel photocatalyst of Bi3.64Mo0.36O6.55 doped with Tm3+/Yb3+ was prepared by a simple coprecipitation method followed by a calcination technology. The as‐synthesized Tm3+/Yb3+‐Bi3.64Mo0.36O6.55 samples were characterized by various analytical methods. The as‐synthesized sample exhibited enhanced photocatalytic activity when degrading Rhodamine B under the irradiation of visible‐light. The photocatalytic degradation efficiency of Tm3+/Yb3+‐Bi3.64Mo0.36O6.55 (95.2%) was higher than that of pure Bi3.64Mo0.36O6.55 (85.2%) in 50 min. Besides, the sample revealed a stable photocatalytic property after four photodegradation cycles. Therefore, this study may provide a better method to obtain stable upconversion photocatalyst degrading organic pollution with greatly improved activity. [ABSTRACT FROM AUTHOR]

Ho 3+ /Yb 3+ co-doped Bi 2 MoO 6 (Ho 3+ /Yb 3+ -Bi 2 MoO 6 ) photocatalyst has been prepared via coprecipitation method followed by an annealing process. The as-synthesized powder exhibits spherical and sheet structure with size of 200 nm-300 nm. Then the photocatalyst was applied to degrade rhodamine (RhB) to measure its photocatalytic activies under visible light irradiation (λ > 400 nm). From the results, Ho 3+ /Yb 3+ -Bi 2 MoO 6 showed higher photocatalytic efficiency (96.48%) than that (79.70%) of bare Bi 2 MoO 6 within 25min. Besides, the photocatalytic activity of the sample keeps well after three photodegradation cycles. This work provides a great way to synthesize photocatalyst with high photocatalytic activity. [ABSTRACT FROM AUTHOR]

As a novel visible-light-driven photocatalyst, Yb 3 + /Ho 3 + co-doped Bi 2 WO 6 (Yb 3 + /Ho 3 + -Bi 2 WO 6 ) was synthesized via a simple hydrothermal method and subsequent a calcination process. The as-synthesized Yb 3 + /Ho 3 + -Bi 2 WO 6 samples were characterized by various analytical methods. The BIW-5 (Yb 3 + /Ho 3 + molar ratios is 5) sample showed the highest photocatalytic activity. The RhB was degraded (99.8%) under visible light irradiation in 20 min. The improved photocatalytic activity could be attributed to the efficient energy transfer between Yb 3 + /Ho 3 + and Bi 2 WO 6 via infrared to visible upconversion and the reduced combination rate of photogenerated electron-hole pairs through doping Yb 3 + /Ho 3 + ions. Therefore, this study may provide a better method to obtain stable upconversion photocatalyst with greatly improved activity. [ABSTRACT FROM AUTHOR]

SrAl 2 O 4 :Eu 3+ down-conversion (DC) nanocrystals were synthesized by a sol–gel method and then doped in TiO 2 as a photoanode in dye-sensitized solar cells (DSSCs). Differential thermal analysis, fourier transform infrared spectroscopy, X-ray diffraction and Brunauer–Emmet–Teller analysis confirmed the formation of SrAl 2 O 4 :Eu 3+ nanocrystals with diameters of ∼47 nm, pore size of ∼25 nm, sintering temperature of 1300 °C. The photoluminescence and UV–vis absorption spectra of the SrAl 2 O 4 :Eu 3+ revealed a DC from ultraviolet light to visible light which matched the strong absorbing region of the N719 dye. The photoelectric conversion efficiency of the DSSCs with a TiO 2 photoanode doped with 3 wt% SrAl 2 O 4 :Eu 3+ was 20% higher than that with a pure TiO 2 photoanode. This phenomenon could be mainly explained by SrAl 2 O 4 :Eu 3+ nanocrystals’ ability of DC and increased the short-circuit current density. It could be minorly due to the p-type doping effect and slightly improved the open-circuit voltage. [ABSTRACT FROM AUTHOR]

SrTiO 3 :Sm 3+ @SiO 2 (STS@SiO 2 ) core–shell nanoparticles were fabricated by Stöber method after a simple hydrothermal process and then being introduced into the TiO 2 photoanode to assemble dye–sensitized solar cells (DSSCs). X–ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and transmission electron microscope (TEM) analysis confirmed the formation of core–shell nanoparticles with cubic structured SrTiO 3 :Sm 3+ (STS) as core, SiO 2 as shell. The photo–fluorescence (PL) and ultraviolet–visible (UV–Vis) absorption spectra of photoanodes with different STS@SiO 2 content indicate a down–conversion from ultraviolet light to visible light which matched the strong absorbing region of the N719 dye. Compared with the pure TiO 2 and STS doped TiO 2 photoanode, STS@SiO 2 doped TiO 2 photoanode showed a greater photovoltaic efficiency. The photoelectric conversion efficiency ( η ) of 5.07% for 10 wt% STS@SiO 2 doped TiO 2 –based DSSC was higher than that of 3.72% for pure TiO 2 –based DSSC and 4.29% for 10 wt% STS doped TiO 2 –based DSSC. This phenomenon could be explained by STS@SiO 2 core–shell nanoparticles’ triple ability to extend spectral response range to the ultraviolet region, suppress the recombination of electron–electrolyte and lengthen the light traveling distance in the photoanode by the scattering. [ABSTRACT FROM AUTHOR]