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The optimal ratio of reaction solutions resulted in excellent performance and product selectivity of CuO/g-C3N4 composites in the photocatalytic CO2 reduction reaction. A pH-dependent chemical exchange saturation transfer (CEST) imaging nuclear magnetic resonance (NMR) method was used to confirm that CuO modification improves the adsorption capacity of CO2. [ABSTRACT FROM AUTHOR]

Engineering surface-active facets of metal cocatalysts is one of the most widely explored strategies to develop advanced photocatalysts and promote photocatalytic solar energy conversion. Here, the surface-active facets of Pd nanocrystals in Pd/g-C 3 N 4 photocatalyst was related to the injection flow rate of PdCl 2. When PdCl 2 was injected at a low flow rate of 7.5 mL/h (7.5-Pd/g-C 3 N 4), the Pd nanocrystals were uniformly dispersed onto the g-C 3 N 4 with exposed low-index {100} and {111} surface-active facets. However, increasing the injection flow rate to 150 mL/h (150-Pd/g-C 3 N 4) formed Pd nanocrystals where only the {100} surface-active facet was exposed. Under visible light irradiation, the 7.5-Pd/g-C 3 N 4 nanocomposite exhibited excellent water splitting activity for hydrogen production (7.61 mmol g−1 h−1), which was significantly better than with the 150-Pd/g-C 3 N 4 nanocomposite (3.3 mmol g−1 h−1). Theoretical calculations and experimental results confirm the importance of the {111} surface-active facets in the 7.5-Pd/g-C 3 N 4 nanocomposite for promoting photocatalytic activity. [Display omitted] • The Pd/g-C 3 N 4 photocatalyst was prepared in a simple one-pot synthesis method. • The surface-active facets of Pd nanocrystals in Pd/g-C 3 N 4 was controlled by the injection flow rate of PdCl 2. • 7.5-Pd/g-C 3 N 4 nanocomposite exhibited excellent photocatalytic activity for H 2 production. • 7.5-Pd/g-C 3 N 4 nanocomposite also shown good performance in varied photocatalytic reactions. [ABSTRACT FROM AUTHOR]

Hydrogels have excellent properties that make them ideally suited as host matrices for the immobilization of photoreactive materials such as TiO2 nanoparticles that serve as catalysts in the photodegradation of organic dyes, which is of great importance in practical water pollution treatment applications. However, the application of hydrogels for this purpose remains poorly studied. The present study addresses this issue by developing two types of hydrogels based on poly(methyl acrylate) and succinamide acid with embedded TiO2 nanoparticles for use as photocatalysts in the photodegradation of organic dyes. The results of the analysis demonstrate that the TiO2 nanoparticles are distributed uniformly in the hydrogel matrices, and the hydrogels maintain their original structures after use. The photodegradation efficiencies of the developed TiO2-hydrogels are demonstrated to be reasonably close to that of freely distributed TiO2 nanoparticles in solution for four different organic dyes. In addition, the results of degradation-regeneration cycling tests demonstrate that immobilizing the TiO2 nanoparticles into the hydrogels greatly reduces their loss during utilization, and the photocatalysts can be easily reused. In fact, the two TiO2-hydrogels retain reasonably high photocatalytic degradation performance after four degradation-regeneration cycles. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have demonstrated a high power conversion efficiency, however, the large energy loss due to non‐radiative recombination is the main challenge for further performance enhancement. Here, a surface treatment strategy is developed by heat‐induced decomposition of a thin interlayer 2,7‐Naphthaleneditriflate (NAP) to in situ reconstruct perovskite energetics. It is verified that the reconstructed perovskite surface energetics match better with the upper hole transport layer compared to the intrinsic condition. Spontaneous generation of n/n− homojunctions between the perovskite film bulk and the surface region promotes hole extraction, enhancing built‐in electric field, and thus significantly suppresses charge recombination at such perovskite hole‐selective heterojunctions. Moreover, the surface decomposed fluorine‐rich complexes passivate the defects and improve the crystallinity of the perovskite film. These advantages are confirmed by a remarkably improved efficiency from 20.52% for the control device to 23.37% for the treated one with excellent stability. The work provides a promising approach of in situ reconstructing perovskite surface and interface for the design of highly efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

Suppressing nonradiative recombination in perovskite solar cells (PSCs) is crucial for increases in their power conversion efficiency and operational stability. Here, it is reported that the synchronous use of a molecule daminozide (DA), as an interlayer and additive to judiciously construct a PTAA:F4TCNQ/DA/perovskite:DA hole‐selective heterojunction that diminishes thermionic losses for collecting holes at the buried interface between perovskites and PTAA:F4TCNQ, and reduces defect sites at such buried interfaces as well as in the perovskite film. The proposed "three birds with one stone" strategy significantly promotes charge transport, and both the interface carrier recombination and defect‐assisted recombination are suppressed. As a result, a remarkably improved efficiency of 22.15% and an impressive fill factor of 83.92% are achieved with excellent device stability compared to 19.04% of the control device. The two values are the highest records for polycrystalline MAPbI3‐based p‐i‐n structural PSCs reported to date. The work provides a promising approach of three birds with one stone, employing a functional material for further improvement of PSC performance. [ABSTRACT FROM AUTHOR]

Biopolymer microgels were designed to encapsulate and protect probiotics during storage and passage through the upper human gastrointestinal tract (GIT), but then release them in the colon. An anaerobic probiotic strain (Bifidobacterium pseudocatenulatum G7; BPG7) was encapsulated within calcium alginate microgels. In some cases, either colloidal antacid (CaCO 3) or colloidal antacid and nanoemulsion (nE) lipid droplets were co-encapsulated with the probiotics. These additives were used to control the porosity and/or internal pH of the microgels. Initially, the viability of free and encapsulated probiotics was evaluated when they were stored at 4 °C for 28 days. The free probiotics rapidly degraded during storage. Encapsulation greatly improved the stability of the probiotics, with the effectiveness depending on the formulation: antacid-microgels > control microgels > antacid-nE-microgels. These effects were mainly attributed to the ability of the colloidal CaCO 3 particles to inhibit molecular diffusion processes. The ability of the microgels to protect the probiotics under simulated gastrointestinal tract (GIT) conditions was then assessed. The free probiotics were completely inactivated when exposed to gastric and small intestine conditions. In contrast, the antacid- and antacid-nE-microgels were highly effective at improving the viability of the probiotics during passage through the upper GIT. Moreover, these microgels were fermented under simulated colonic conditions, thereby releasing the probiotics. These results suggest that antacid-loaded calcium alginate microgels can be used for the encapsulation, protection, and colonic delivery of probiotics. Nevertheless, further studies are required using in vivo models. Image 1 • Antacid alginate-microgels greatly improved the stability of the probiotics during storage. • The antacid agent/antacid and nanoemulsion improved the viability of the probiotics during digestion. • The alginate microgels was fermented to release probiotics under simulated colonic conditions. [ABSTRACT FROM AUTHOR]

In recent years, coordination polymers constructed from multidentate carboxylate ligands and N‐containing ligands have attracted much attention since these ligands can adopt a rich variety of coordination modes which can lead to crystalline products with intriguing structures and interesting properties. A new coordination polymer, namely poly[[diaqua[μ‐2,7‐bis(1H‐imidazol‐1‐yl)fluorene‐κ2N3:N3′][μ‐5,5′‐methylenebis(3‐carboxy‐2,4,6‐trimethylbenzoato)‐κ2O1:O1′]zinc(II)] hemihydrate], {[Zn(C23H22O8)(C19H14N4)(H2O)2]·0.5H2O}n, 1, was prepared by the self‐assembly of Zn(NO3)2·6H2O with 5,5′‐methylenebis(2,4,6‐trimethylisophthalic acid) (H4BTMIPA) and 2,7‐bis(1H‐imidazol‐1‐yl)fluorene (BIF) under solvothermal conditions. The structure of 1 was determined by elemental analysis, single‐crystal X‐ray crystallography, powder X‐ray diffraction, IR spectroscopy and thermogravimetric analysis. Each ZnII ion is six‐coordinated by two O atoms from two H2BTMIPA2− ligands, by two N atoms from two BIF ligands and by two water molecules, forming a distorted octahedral ZnN2O4 coordination geometry. Adjacent ZnII ions are linked by H2BTMIPA2− ligands and BIF ligands, leading to the formation of a two‐dimensional (2D) (4,4)‐sql network, and intermolecular hydrogen‐bonding interactions connect the 2D layer structure into the three‐dimensional (3D) supramolecular structure. Each 2D layer contains two kinds of helices with the same direction, which are opposite in adjacent layers. The luminescence properties of complex 1 in the solid state have also been investigated. A new two‐dimensional coordination polymer based on 5,5′‐methylenebis(2,4,6‐trimethylisophthalic acid) and 2,7‐bis(1H‐imidazol‐1‐yl)fluorene has been prepared and structurally characterized. [ABSTRACT FROM AUTHOR]