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Herein, we demonstrate a coating-etching strategy to directly synthesize hollow Prussian blue (PB) nanocubes with well-dispersed Ag nanoparticles (denoted as Ag-HPB). The method is accomplished by introduction of PB precursors, K 3 Fe(CN) 6 and Fe 3+ into a reaction system containing AgNO 3 and ascorbic acid, in which a series reactions contain formation of Ag nanoparticles, coating of PB on the nanoparticles, and diffusion of Ag into the PB frameworks occur. The strategy for preparation of the hollow structured Ag-HPB is intrinsically simple and does not require pre-preparation of any sacrificial templates or toxic etching agents. The obtained Ag-HPB nanocubes possess uniform size (69 nm), well-defined hollow structure, strong near-infrared photothermal conversion capacity, and excellent photoacoustic and magnetic resonance imaging abilities. Furthermore, an injectable photothermal implants are prepared for the first time by mixing the Ag-HPB nanocubes with clinically used biological glue, which significantly enhance photothermal anti-tumor efficacy, showing great potential for clinical tumor treatment. [ABSTRACT FROM AUTHOR]

A dual-functional ionic liquid additive, 1-butyl-3-methylimidazolium hydrogen sulfate (BMIHSO 4), is developed to tune the preferential Zn(002) crystallographic texture and simultaneously suppress the hydroxide sulfate accumulation on Zn anode by dynamically manipulating electrolyte pH-surroundings. The effective suppression of Zn dendrite growth enables a Zn symmetrical cell cycling stably to over one year. [Display omitted] Zn anodes suffer from the formation of uncontrolled dendrites aggravated by the uneven electric field and the insulating by-product accumulation in aqueous zinc-ion batteries (AZIBs). Here, an effective strategy implemented by 1-butyl-3-methylimidazolium hydrogen sulfate (BMIHSO 4) additive is proposed to synergistically tune the crystallographic orientation of zinc deposition and suppress the formation of zinc hydroxide sulfate for enhancing the reversibility on Zn anode surface. As a competing cation, BMI+ is proved to preferably adsorb on Zn-electrode compared with H 2 O molecules, which shields the "tip effect" and inhibits the Zn-deposition agglomerations to inducing the horizontal growth along Zn (002) crystallographic texture. Simultaneously, the protonated BMIHSO 4 additives could remove the detrimental OH– in real-time to fundamentally eliminate the accumulation of 6Zn(OH) 2 ·ZnSO 4 ·4H 2 O and Zn 4 SO 4 (OH) 6 ·H 2 O on Zn anode surface. Consequently, Zn anode exhibits an ultra-long cycling stability of one year (8762 h) at 0.2 mA cm−2/0.2 mAh cm−2, 3600 h at 2 mA cm−2/2 mAh cm−2 with a high plating cumulative capacity of 3.6 Ah cm−2, and a high average Coulombic efficiency of 99.6 % throughout 1000 cycles. This work of regulating Zn deposition texture combined with eliminating notorious by-products could offer a desirable way for stabilizing the Zn-anode/electrolyte interface in AZIBs. [ABSTRACT FROM AUTHOR]

Chemical oxo-precipitation (COP) has become a promising method for treating boron wastewater at room temperature; it uses hydrogen peroxide to convert boric acid to perborate species, which are precipitated using alkaline earth metals. In this work, solubility models of barium perborates were established to predict residual boron levels from COP. The solubility product constants (pK sp ) of two major barium perborates – amorphous Ba(B(OH) 3 OOH) 2 (A-BaPB) and crystalline BaB(OH) 2 (OO) 2 B(OH) 2 (C-BaPB) – were experimentally estimated (8.335 ± 0.109 and 9.190 ± 0.057, respectively) to define the solubility curves of BaPBs at given pH, ionic strength and concentrations of barium and peroxide species. The characterization of precipitates that were formed by COP confirmed that the boron levels in aqueous solution were governed by the phase transformation of A-BaPB to C-BaPB. The predictive solubility models of barium perborates can perfectly predict the residual concentration of boron after COP treatment and can be used to optimize the process for reducing boron concentrations in wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] In recent years, branched or star-shaped Au nanostructures composed of core and protruding arms have attracted much attention due to their unique optical properties and morphology. As the clinically adapted nanoagent, prussian blue (PB) has recently gained widespread attention in cancer theranostics with potential applications in magnetic resonance (MR) imaging. In this article, we propose a hybrid star gold nanostructure（Au-star@PB）as a novel theranostic agent for T1-weighted magnetic resonance imaging (MRI)/ photoacoustic imaging（PAI） and photothermal therapy (PTT) of tumors. Importantly, the Au-star@PB nanoparticles function as effective MRI/PA contrast agents in vivo by increasing T1-weighted MR/PAI signal intensity and as effective PTT agents in vivo by decreasing the tumor volume in MCF-7 tumor bearing BALB / c mouse model as well as in vitro by lessening tumor cells growth rate. Interestingly, we found the main photothermal effect of Au-star@PB is derived from Au-star, but not PB. In summary, the hybrid structure of Au-star@PB NPs with good biological safety, significant photostability, dual imaging capability, and high therapeutic efficiency, might offer a novel avenue for the future diagnosis and treatment of cancer. [ABSTRACT FROM AUTHOR]

Searching for promising visible-light photocatalysts for overall water splitting into hydrogen and oxygen is a very challenging task to solve the energy crisis and environment pollution. The widely-used tantalate and niobate perovskite photocatalysts have two drawbacks, i.e., the large energy band gap (∼ 3.2–4.6 eV) and low electron (hole) mobility 102 (101) cm2 V−1 s−1, which greatly limit their photocatalytic performance. Here, based on the powerful first-principles and accurate GW calculations, we design several novel two-dimensional (2D) Ruddlesden-Popper (RP) type (n = 1) perovskite oxynitrides A 2 BO 3 N (A = Ca, Sr, Ba and B = Ta, Nb) and their bonded heterostructures and comprehensively investigate their interlayer coupling, electronic structures, transport and photocatalytic characteristics. We find that 2D A 2 BO 3 N oxynitrides have a reduced direct band gap at Γ -point, especially for three-layer (3L) Ba 2 NbO 3 N and 1L-Sr 2 NbO 3 N/1L-Ba 2 NbO 3 N bonded heterostructure with the optimized band gap ∼ 2.0 eV. Compared with tantalate and niobate perovskite oxides, the electron (hole) mobility increases 1–2 orders of magnitude up to 103–104 (102–103) cm2 V−1 s−1. A fast electron-hole vertical transport across the heterointerface and remarkable electron-hole separation can be realized in 1L-Sr 2 NbO 3 N/1L-Ba 2 NbO 3 N bonded heterostructure due to its strong interface Ba-O and Sr-O bonds and type-II band offset. Compared with the well-known photocatalysts, such as BiVO 4 and MoS 2 /g-C 3 N 4 , an improved optical absorption (8 × 104 cm−1) in A 2 BO 3 N is obtained in the visible region. The 2D RP-type perovskite oxynitrides 3L-Ba 2 NbO 3 N and 1L-Sr 2 NbO 3 N/1L-Ba 2 NbO 3 N are powerful visible-light photocatalysts for overall water splitting. [ABSTRACT FROM AUTHOR]