Journal of Solid State Chemistry最新文献

Herein, two kinds of conjugated microporous polymers (CMPs) containing phenolic hydroxyl groups, CMP-OH1 and CMP-OH2, were prepared by Sonogashira−Hagihara coupling reaction, which were used as metal-free organic photocatalysts for photocatalytic degradation of cationic organic dyes. The hollow nanosphere had abundant surface defect sites that facilitated the separation of photogenerated electron-hole pairs, which enhanced the photocatalytic activity of CMP-OH1. Under visible light irradiation, the CMP-OH1 degradation efficiency for Methylene blue (MB) reached 99.5 % within 60 min, while the degradation efficiency for Rhodamine B (RhB) attained 99.9 % within 30 min. After 5 cycles, the degradation rate of cationic organic dyes by CMP-OH1 exceeded 92 %. Notably, the photocatalytic mechanism of CMP-OH1 has been examined that superoxide anion radical (·O₂⁻) is the principal active substance produced in the photocatalytic degradation of cationic organic dyes. This work opens up a new way of treating dye-contaminated water with hollow nanosphere CMPs containing phenolic hydroxyl groups.

Cu₂Se as a thermoelectric material has gained popularity in recent years because of the excellent properties resulting from its superionicity. In this study, Cu_2-xAg_xSe (x = 0, 0.05, 0.15, 0.25) samples were fabricated through the spark plasma sintering method, followed by a comprehensive microstructure and thermoelectric properties analysis. The results indicated that, when the doping amount of Ag is x ≥ 0.05, the CuAgSe phase is produced at room temperature, which introduces an energy filtering effect, resulting in an augmentation of the Seebeck coefficient and a reduction in the electrical conductivity. Ag doping leads to point defects, the disorder of cations, and the phase boundaries which increases phonon scattering, resulting in reduced thermal conductivity. At 773 K, the thermal conductivity decreases from 1.10 Wm⁻¹K⁻¹ for Cu₂Se to 0.41 Wm⁻¹K⁻¹ for Cu_1.75Ag_0.25Se. Compared to ZT ∼ 0.8 for the intrinsic Cu₂Se sample, the ZT of Cu_1.75Ag_0.25Se reaches 1.41 at 773 K, which is an increase of over 70 %.

Commercial WLEDs in a cold white light with a lower color rendering index(Ra) and higher correlated color temperature due to the lack of a red component. Therefore, we propose to develop a non-oxide rare-earth-based red phosphor with excellent luminescence performance and thermal stability. The crystal phases, particle morphology, elemental states, photoluminescence(PL) behavior, and electronic structure were characterized. The Density Functional Theory (DFT) calculation was carried out to reveal the mechanisms of the crystal and electronic structures on the photoluminescent properties and the associated energy-transfer mechanisms. Furthermore, the optimal double-doped KYF₄ phosphor with negative thermal quenching and the yellow phosphor YAG:Ce³⁺ were co-assembled into LEDs, which exhibited a warm white light with a color rendering index of 93.9 and a correlated color temperature of 4275 K under a driving current of 9 mA. These results indicate that the optimized phosphor has considerable potential for application in red light supplements for WLEDs.

The development of metal ion detection probes with high sensitivity and selectivity is of utmost importance for the promotion of public health and environmental sustainability. In this work, a series of ratiometric fluorescent probes (RhB@UiO-67-NH₂) were successfully prepared using a one-pot method for the detection of metal ions, particularly As⁵⁺ and Fe³⁺. Notably, the ratiometric fluorescent probe RhB@UiO-67-NH₂ (1:4) demonstrates dual functionality as a Fe³⁺ turn-off probe and an As⁵⁺ turn-on probe. The limits of detection (LODs) for As⁵⁺ and Fe³⁺ using RhB@UiO-67-NH₂ (1:4) were determined to be 0.521 μM (39.03 ppb) and 0.107 μM (5.97 ppb), respectively, which were the lowest records of reported LMOFs so far. The fluorescence quenching of Fe³⁺ can be attributed to various mechanisms such as fluorescence resonance energy transfer (FRET), photoinduced electron transfer (PET), and competitive absorption (CA). Additionally, the fluorescence enhancement of As⁵⁺ is primarily due to absorbance-caused enhancement (ACE) and PET. Moreover, the composite material RhB@UiO-67-NH₂ (1:4) exhibited excellent anti-interference capability and reproducibility for detecting Fe³⁺ and As⁵⁺. The removal efficiency of As⁵⁺ by RhB@UiO-67-NH₂ (1:4) exceeded 50.9 % when the initial concentration of As⁵⁺ was below 20 mg/L. This work presents a valuable reference for future investigations and utilization of As⁵⁺ and Fe³⁺ sensing.

Spin-coating pre-fabricated NiO_x nanocrystals using an annealing-free process is a compatible technique for fabricating the hole transport layer in n-i-p structured perovskite solar cells. The solvothermal method, assisted by long-chain fatty acids or amines such as oleic acid and oleylamine, has demonstrated the applicability of fabricating NiO_x nanoparticles with uniform morphology and size. However, the long-chain fatty acids or amines covering the NiO_x nanoparticles cannot be removed at low temperature, obstructing the transport of photo-generated holes due to their insulating characteristics. Herein, triphenylphosphine is employed to replace a portion of oleylamine in the solvothermal reaction solution. Experimental results demonstrate that the introduction of triphenylphosphine does not affect the dispersion of the synthesized NiO_x nanoparticles in toluene. The as-fabricated n-i-p structured device receives an efficiency of 12.63 %. Thereafter, Li⁺ doping and Li⁺-Mg²⁺ co-doping strategies are used to further enhance the devices' performance. The best-behaved device with Li⁺-Mg²⁺ co-doping NiO_x hole transport layer acquires an efficiency of 16.20 %. This research provides a practical approach for fabricating efficient NiO_x hole transport materials for n-i-p structured perovskite solar cells.

The photocatalytic reduction of uranium from nuclear wastewater represents a promising method for both uranium extraction and environmental remediation. This approach facilitates the recovery of uranium resources for the nuclear industry while addressing environmental pollution. Despite significant research advancements, there remains a need for cost-effective and environmentally friendly catalytic materials. In this context, we present a two non-metal O, P co-doped g-C₃N₄ (OPCN) synthesized via a simple one-step thermo-polymerization in air. OPCN demonstrates a high uranium reduction efficiency of 94.9 % under white LED light illumination. Even after five cycles, OPCN maintained a reduction efficiency of 81.7 %, highlighting its stability and reusability. Additionally, OPCN also performs effectively in uranium reduction under natural sunlight and exhibits impressive antimicrobial properties. These features position OPCN as a promising candidate for practical environmental applications.

It is imperative to carry out more research on the proton conduction in metal-organic frameworks (MOFs) made of main group metals. Inspired by this, we synthesized a 3D indium-based MOF, [In(BDC-NH₃)(BDC-NH₂)]∙1.5DMF∙1.5H₂O (namely In-MOF 1), which is made up of [In(CO₂)₄] metal nodes and 2-amino terephthalic acid (H₂BDC-NH₂) organic linkers. Meanwhile, organic ligand functionalization has been proven to be one of the effective techniques to boost the proton conductivity of the corresponding metal-organic frameworks. In light of this, the functionalized MOF was successfully synthesized using In(III) ions and H₂BDC-NH₂, which not only has excellent water stability but also bear some hydrophilic groups such as -NH₂ and carboxylate units, which may act as a pivotal role in improving the proton conductivity (σ). Consequently, the σ of In-MOF 1 was thoroughly examined. As expected, its optimal σ can reach 0.81 × 10^-2 S⋅cm^-1 under 100 °C and 98% relative humidity (RH), substantially higher than the In-MOF composed only of terephthalic acid. Finally, we estimated its activation energy (E_a) at 98% and 68% RHs using the Arrhenius equation, and the proton transport mechanism was further explored.

Al is the most abundant metallic element, and plays an important role in the production of life. However, excessive accumulation of Al³⁺ in our bodies poses potential threats to our health. Therefore, highly effective detection of Al³⁺ has been an important issue. In this work, a new La-MOF with a three-dimensional structure (HNU-96) has been synthesized, which can serve as effective fluorescence sensor to Al³⁺ detection. Due to the ion exchange between La³⁺ and Al³⁺ and the weak interaction between Al³⁺ and O atoms, the fluorescence quenching of the La-MOF was observed. HNU-96 shows high selectivity for Al³⁺ detection with the limit of detection (LOD) as low as 2.3 × 10⁻⁶ M. Furthermore, HNU-96 shows excellent anti-interference for the Al³⁺ detection. This work provides the feasible strategy for the metal ion detection.

Perovskite (PVK) halides represent versatile materials in both production and application. Given their continuous focus in research, this article aims to provide a comprehensive review of lead-free perovskites based on antimony, characterized by the formula Cs₃Sb₂X₉, with X representing Cl^-, I^- or Br^-. The objective is to present the latest research findings at the time of writing this document, categorized by applications and their corresponding outcomes. Although this compound is predominantly studied in the domain of photovoltaic devices, it is important to acknowledge its relevance in other applications. Therefore, this article also investigates its utilization in other areas such as photocatalysis and light-emitting diodes (LEDs). Key parameters such as crystalline structure and band gap (E_g) are highlighted, given their significance in perovskite characterization. In essence, this work not only serves to disseminate knowledge about these materials but also aims to catalyze further research aimed at enhancing the utilization of lead-free perovskites across various domains.

The rational design and construction of polyoxotitanium clusters with outstanding photoelectrochemical activity represents a significant challenge in the field. Herein, employing ferrocene as a photosensitizer and incorporating diverse auxiliary ligands, we have successfully constructed a family of structurally varied ferrocene-sensitized polyoxotitanium clusters, formulated as Ti₃ (μ₃-O) (Fcc)₂(OⁱPr)₈ (Ti₃Fcc-1, Fcc = ferrocenecarboxylic acid), Ti₃ (μ₃-O) (Fcc) (L1) (OⁱPr)₈ (Ti₃Fcc-2, L1 = 6-amino-m-toluenesulfonic acid), Ti₆ (μ₃-O)₂ (μ₂-O) (Fcc)₂ (L2)₂(OⁱPr)₁₀ (Ti₆Fcc-1, L2 = salicylhydroxamic acid), Ti₆ (μ₃-O)₄(Fcc)₂ (L3)₂(OⁱPr)₁₀ (Ti₆Fcc-2, L3 = diisopropanolamine), and Ti₈ (μ₃-O)₄(Fcdc)₄ (L4)₂(OⁱPr)₁₀ (Ti₈Fcdc, Fcdc = 1,1-ferrocenedicarboxylic acid, L4 = triisopropanolamine). The incorporation of auxiliary groups can effectively regulate the structure of ferrocene-functionalized polyoxotitanium clusters, resulting in a gradual growth of the cluster core from Ti₃ to Ti₆, and ultimately reaching Ti₈. Moreover, these titanium-oxo clusters exhibit displayed enhanced visible light absorption and narrow bandgaps, which are primarily attributed to the charge transport from Fcc/Fcdc and ancillary groups to the cluster core. These Ti-oxo clusters were also used as electrode precursors for investigating their photoelectric behaviors and exhibited clear photocurrent responses. This work not only expands ferrocene-sensitized titanium-oxo clusters library, but also provides guidance for the rational design and controllable construction on titanium-based photoactive materials.