Metallic zinc is an attractive anode material for aqueous rechargeable batteries because of its high theoretical capacity and low cost. However, state-of-the-art zinc anodes suffer from low coulombic efficiency and severe dendrite growth during stripping/plating processes, hampering their practical applications. Here we show that eutectic-composition alloying of zinc and aluminum as an effective strategy substantially tackles these irreversibility issues by making use of their lamellar structure, composed of alternating zinc and aluminum nanolamellas. The lamellar nanostructure not only promotes zinc stripping from precursor eutectic Zn 88 Al 12 (at%) alloys, but produces core/shell aluminum/aluminum sesquioxide interlamellar nanopatterns in situ to in turn guide subsequent growth of zinc, enabling dendritefree zinc stripping/plating for more than 2000 h in oxygen-absent aqueous electrolyte. These outstanding electrochemical properties enlist zinc-ion batteries constructed with Zn 88 Al 12 alloy anode and K x MnO 2 cathode to deliver high-density energy at high levels of electrical power and retain 100% capacity after 200 hours.

The discovery of high efficiency narrow-band green-emitting phosphors is a major challenge in backlighting light-emitting diodes (LEDs). Benefitting from highly condensed and rigid framework structure of UCr C -type compounds, a next-generation narrow green emitter, RbLi(Li SiO ) :Eu (RLSO:Eu ), has emerged in the oxide-based family with superior luminescence properties. RLSO:Eu phosphor can be efficiently excited by GaN-based blue LEDs, and shows green emission at 530 nm with a narrow full width at half maximum of 42 nm, and very low thermal quenching (103%@150 °C of the integrated emission intensity at 20 °C), however its chemical stability needs to be improved later. The white LED backlight using optimized RLSO:8%Eu phosphor demonstrates a high luminous efficacy of 97.28 lm W and a wide color gamut (107% National Television System Committee standard (NTSC) in Commission Internationale de L'Eclairage (CIE) 1931 color space), suggesting its great potential for industrial applications as liquid crystal display (LCD) backlighting.

Phosphor-converted white LEDs rely on combining a blue-emitting InGaN chip with yellow and red-emitting luminescent materials. The discovery of cyan-emitting (470–500 nm) phosphors is a challenge to compensate for the spectral gap and produce full-spectrum white light. Na 0.5 K 0.5 Li 3 SiO 4 :Eu 2+ (NKLSO:Eu 2+ ) phosphor was developed with impressive properties, providing cyan emission at 486 nm with a narrow full width at half maximum (FWHM) of only 20.7 nm, and good thermal stability with an integrated emission loss of only 7% at 150 °C. The ultra-narrow-band cyan emission results from the high-symmetry cation sites, leading to almost ideal cubic coordination for UCr 4 C 4 -type compounds. NKLSO:Eu 2+ phosphor allows the valley between the blue and yellow emission peaks in the white LED device to be filled, and the color-rendering index can be enhanced from 86 to 95.2, suggesting great applications in full-spectrum white LEDs.

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Water splitting has been greatly limited by the sluggish kinetics of the oxygen evolution reaction (OER). High-oxidation-state metal species are required as the favorable active sites in OER. Here, amorphous Cox-Fe-B (x is the molar ratio of Co/Fe), Co-B, and Fe-B compounds were successfully synthesized as the oxygen evolution electrocatalysts. The calculation of turnover frequency (TOF) indicates that both the Co and Fe sites are active for OER. Cyclic voltammetry, X-ray photoelectron spectroscopy, and long-term stability curves were used to demonstrate that Fe can stabilize Co in a higher oxidation level and meanwhile promote the generation of OOH-like species (the key intermediates for OER). The reduced impedance for Co2-Fe-B (compared with that for Fe-B and Co-B) obtained from the electrochemical impedance spectra confirms the enhanced conductivity for the Co2-Fe-B. This optimal sample on Cu substrate shows a low overpotential of 0.298 V at the current density of 10 mA cm with a decreased overpotential of 42 mV compared to that of Co-B. The Co2-Fe-B catalyst also exhibits a small Tafel slope of 62.6 mV/dec and good stability. The enhanced performance could be attributed to the synergistic effect of the increased population of high-oxidation-state metal-OOH species and the promoted conductivity of the catalyst. A solar-to-hydrogen energy conversion efficiency of 4.2% and a Faradaic efficiency of 97.2% can be achieved by connecting the HER and as-prepared OER electrodes to a crystalline silicon solar cell.

A robust and stable narrow-band green emitter is recognized as a key enabler for wide-color-gamut liquid crystal display (LCD) backlights. Herein, an emerging rare earth silicate phosphor, RbNa(Li 3 SiO 4 ) 2 :Eu 2+ (RN:Eu 2+ ) with exceptional optical properties and excellent thermal stability, is reported. The resulting RN:Eu 2+ phosphor presents a narrow green emission band centered at 523 nm with a full width at half maximum of 41 nm and excellent thermal stability (102%@425 K of the integrated emission intensity at 300 K). RN:Eu 2+ also shows a high quantum efficiency, an improved chemical stability, and a reduced Stokes shift owing to the modified local environment, in which [NaO 8 ] cubes replace [LiO 4 ] squares in RbLi(Li 3 SiO 4 ) 2 :Eu 2+ via polyhedron transformation. White light-emitting diode (wLED) devices with a wide color gamut (113% National Television System Committee (NTSC)) and high luminous efficacy (111.08 lm W −1 ) are obtained by combining RN:Eu 2+ as the green emitter, K 2 SiF 6 :Mn 4+ as the red emitter, and blue-emitting InGaN chips. Using these wLEDs as backlights, a prototype 20.5 in. LCD screen is fabricated, demonstrating the bright future of stable RN:Eu 2+ for wide-colorgamut LCD backlight application.

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