Highly Enhanced and Switchable Photoluminescence Properties in Pillared Layered Hydroxides Stabilizing Ce³⁺

We have developed pillared layered rare earth hydroxides showing the reversible photoluminescence switching via reducing–oxidizing processes. An air-stable Ce³⁺-based host, Ce₂(OH)₄SO₄·2H₂O, was successfully synthesized via a homogeneous alkalization protocol to precipitate Ce³⁺ ions from a solution of the relevant salt. Structural analysis revealed that the compound consists of cationic layers of {[Ce­(OH)₂(H₂O)]⁺}_∞, linked by sulfate bidentate ligands to construct a layered framework architecture. Tb³⁺ ion was incorporated into this host lattice to form a solid solution across the full compositional range. At an optimized doping of ∼30%, the characteristic green emission was enhanced by ∼20 times, being promoted by the efficient energy transfer from Ce³⁺ to Tb³⁺. The emission could be drastically diminished upon the action of the KMnO₄ oxidizing reagent, which induced the transformation of Ce³⁺ to Ce⁴⁺. Characterizations by X-ray diffraction and X-ray photoelectron spectroscopy showed that the oxidation of Ce³⁺ occurs without degradation of the crystalline framework. The emission could be recovered to its original intensity by the reduction treatment with ascorbic acid. This photoluminescence switching behavior was detectable by the eye and exhibited high reversibility

New Family of Lanthanide-Based Inorganic–Organic Hybrid Frameworks: Ln₂(OH)₄[O₃S(CH₂)_<i>n</i>SO₃]·2H₂O (Ln = La, Ce, Pr, Nd, Sm; <i>n</i> = 3, 4) and Their Derivatives

We report the synthesis and structure characterization of a new family of lanthanide-based inorganic–organic hybrid frameworks, Ln₂(OH)₄[O₃S­(CH₂)_<i>n</i>SO₃]·2H₂O (Ln = La, Ce, Pr, Nd, Sm; <i>n</i> = 3, 4), and their oxide derivatives. Highly crystallized samples were synthesized by homogeneous precipitation of Ln³⁺ ions from a solution containing α,ω-organodisulfonate salts promoted by slow hydrolysis of hexamethylenetetramine. The crystal structure solved from powder X-ray diffraction data revealed that this material comprises two-dimensional cationic lanthanide hydroxide {[Ln­(OH)₂(H₂O)]⁺}_∞ layers, which are cross-linked by α,ω-organodisulfonate ligands into a three-dimensional pillared framework. This hybrid framework can be regarded as a derivative of UCl₃-type Ln­(OH)₃ involving penetration of organic chains into two {LnO₉} polyhedra. Substitutional modification of the lanthanide coordination promotes a 2D arrangement of the {LnO₉} polyhedra. A new hybrid oxide, Ln₂O₂[O₃S­(CH₂)_<i>n</i>SO₃], which is supposed to consist of alternating {[Ln₂O₂]²⁺}_∞ layers and α,ω-organodisulfonate ligands, can be derived from the hydroxide form upon dehydration/dehydroxylation. These hybrid frameworks provide new opportunities to engineer the interlayer chemistry of layered structures and achieve advanced functionalities coupled with the advantages of lanthanide elements

A Superlattice of Alternately Stacked Ni–Fe Hydroxide Nanosheets and Graphene for Efficient Splitting of Water

Cost-effective electrocatalysts based on nonprecious metals for efficient water splitting are crucial for various technological applications represented by fuel cell. Here, 3<i>d</i> transition metal layered double hydroxides (LDHs) with varied contents of Ni and Fe were successfully synthesized through a homogeneous precipitation. The exfoliated Ni–Fe LDH nanosheets were heteroassembled with graphene oxide (GO) as well as reduced graphene oxide (rGO) into superlattice-like hybrids, in which two kinds of oppositely charged nanosheets are stacked face-to-face in alternating sequence. Heterostructured composites of Ni_2/3Fe_1/3 LDH nanosheets and GO (Ni_2/3Fe_1/3-GO) exhibited an excellent oxygen evolution reaction (OER) efficiency with a small overpotential of about 0.23 V and Tafel slope of 42 mV/decade. The activity was further improved <i>via</i> the combination of Ni_2/3Fe_1/3 LDH nanosheets with more conductive rGO (Ni_2/3Fe_1/3-rGO) to achieve an overpotential as low as 0.21 V and Tafel plot of 40 mV/decade. The catalytic activity was enhanced with an increased Fe content in the bimetallic Ni–Fe system. Moreover, the composite catalysts were found to be effective for hydrogen evolution reaction. An electrolyzer cell powered by a single AA battery of 1.5 V was demonstrated by using the bifunctional catalysts

A Superlattice of Alternately Stacked Ni–Fe Hydroxide Nanosheets and Graphene for Efficient Splitting of Water

Cost-effective electrocatalysts based on nonprecious metals for efficient water splitting are crucial for various technological applications represented by fuel cell. Here, 3<i>d</i> transition metal layered double hydroxides (LDHs) with varied contents of Ni and Fe were successfully synthesized through a homogeneous precipitation. The exfoliated Ni–Fe LDH nanosheets were heteroassembled with graphene oxide (GO) as well as reduced graphene oxide (rGO) into superlattice-like hybrids, in which two kinds of oppositely charged nanosheets are stacked face-to-face in alternating sequence. Heterostructured composites of Ni_2/3Fe_1/3 LDH nanosheets and GO (Ni_2/3Fe_1/3-GO) exhibited an excellent oxygen evolution reaction (OER) efficiency with a small overpotential of about 0.23 V and Tafel slope of 42 mV/decade. The activity was further improved <i>via</i> the combination of Ni_2/3Fe_1/3 LDH nanosheets with more conductive rGO (Ni_2/3Fe_1/3-rGO) to achieve an overpotential as low as 0.21 V and Tafel plot of 40 mV/decade. The catalytic activity was enhanced with an increased Fe content in the bimetallic Ni–Fe system. Moreover, the composite catalysts were found to be effective for hydrogen evolution reaction. An electrolyzer cell powered by a single AA battery of 1.5 V was demonstrated by using the bifunctional catalysts

Association of albumin to non-high-density lipoprotein cholesterol ratio with mortality in peritoneal dialysis patients

Malnutrition and inflammation are associated with mortality in peritoneal dialysis (PD) patients. Serum albumin and non-high-density lipoprotein cholesterol (non-HDL-C) are independently associated with mortality in PD patients. Combining albumin and non-HDL-C with mortality may be more plausible in clinical practice. This retrospective cohort study included 1954 Chinese PD patients from 1 January 2009 to 31 December 2016. Kaplan–Meier curve was used to determine the relationship between albumin to non-HDL-C ratio and all-cause mortality. Cox regression analysis was applied to assess the independent predictive value while adjusting for confounding factors. Competitive risk analysis was used to examine the effects of other outcomes on all-cause mortality prognosis. In the 33-month follow-up period, there were 538 all-cause deaths. Kaplan–Meier analysis presented significant differences in all-cause mortality. Multivariate Cox regression showed that the risk of all-cause mortality was lower in the moderate group (9.36–12.79) (HR, 0.731; 95% CI, 0.593–0.902, p = 0.004) and the highest group (>12.79) (HR, 0.705; 95% CI, 0.565–0.879, p = 0.002) compared to the lowest group (≤9.36). Competitive risk analysis revealed significant differences for all-cause mortality (p  Low albumin to non-HDL-C ratio was associated with a high risk of all-cause mortality in PD patients. It may serve as a potential prognostic biomarker in PD patients.</p