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Exploring efficient and stable halide perovskite-based photocatalysts is a great challenge due to the balance between the photocatalytic performance, toxicity, and intrinsic chemical instability of the materials. Here, the environmentally friendly lead-free perovskite Cs2AgBiBr6 confined in the mesoporous TiO2 crystal matrix has been designed to enhance the charge carrier extraction and utilization for efficient photocatalytic rifampicin degradation. The as-prepared Cs2AgBiBr6/TiO2 catalyst was stable in air for over 500 days. An S-scheme heterojunction was formed between the (004) plane of Cs2AgBiBr6 and the (101) plane of TiO2 through the Bi-O-Br bonds. The built-in electric field at the interface efficiently promoted the photoinduced charge separation and carrier extraction. The Cs2AgBiBr6/TiO2-200 showed a 92.83% degradation efficiency of rifampicin within 80 min under simulated sunlight illumination (AM 1.5G 100 mW cm-2). This work offers an effective way for the construction of halide perovskite-based photocatalysts with high photocatalytic performance, good stability, and low toxicity simultaneously.
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The controllable and low-cost synthesis of nanometal particles is highly desired in scientific and industrial research. Herein, size-tunable Ru nanoparticles were synthesized by using a novel ion-sieve-confined reduction method. The H2TiO3 ion-sieve was used to adsorb Ru3+ into the hydroxyl-enriched porous [TiO3]2- layers. The confined environment of the interlayer space facilitates Ru-Ru collision and bonding during annealing, achieving a precise reduction from Ru3+ to Ru0 without additional reductants. Owing to the confinement effect, Ru0 nanoparticles are uniformly embedded in the pores on the surface of the postannealed TiO2 matrix (Ru@TiO2). Ru@TiO2 exhibited a lower overpotential than Pt/C (57 vs 87 mV at 10 mA cm-2) for the HER in 0.1 M KOH solution. The confinement-induced reduction of metal ions was also preliminarily proved in ion-exchanged zeolites, which provides facile and abundant approaches for the size-controllable synthesis of nanometal catalysts with high catalytic activity.
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Knowledge of structure-property relationships in solids with intrinsic low thermal conductivity is crucial for fields such as thermoelectrics, thermal barrier coatings, and refractories. Herein, we propose a new "rigidness in softness" structural scheme for intrinsic low lattice thermal conductivity (κL), which embeds rigid clusters into the soft matrix to induce large lattice anharmonicity, and accordingly discover a new series of chalcogenides Pt3Bi4Q9 (Q = S, Se). Pt3Bi4S9-xSex (x = 3, 6) achieved an intrinsic ultralow κL down to 0.39 W/(m K) at 773 K, which is considerably low among the Bi chalcogenide thermoelectric materials. Pt3Bi4Q9 contains the rigid cubic [Pt6Q12]12- clusters embedded in the soft Bi-Q sublattice, involving multiple bonding interactions and vibration hierarchy. The hierarchical structure yields a large lattice anharmonicity with high Grüneisen parameters (γ) 1.97 of Pt3Bi4Q9, as verified by the effective scatter of low-lying optical phonons toward heat-carrying acoustic phonons. Consequently, the rigid-soft coupling significantly inhibits heat propagation, exhibiting low acoustic phonon frequencies (â¼25 cm-1) and Debye temperatures (ΘD = 170.4 K) in Pt3Bi4Se9. Owing to the suppressed κL and considerable power factor (PF), the ZT value of Pt3Bi4S6Se3 can reach 0.56 at 773 K without heavy carrier doping, which is competitive among the pristine Bi chalcogenides. Theoretical calculations predicted a large potential for performance improvement via proper doping, indicating the great potential of this structure type for promising thermoelectric materials.
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Stannous sulfide (SnS), a conversion-alloying type anode for sodium-ion batteries, is strong Na+ storage activity, a low voltage platform, and high theoretical capacity. However, grain pulverization induced by intolerable volume change and phase aggregation causes quick capacity degradation and unsatisfactory rate capability. Herein, a novel "lasagna" strategy is developed by embedding a SnS layer into the interlayer of an electrochemically robust and electron-active TaS2 to form a misfit layered (SnS)1.15TaS2 superlattice. For Na+ storage, the rationally designed (SnS)1.15TaS2 anode exhibits high specific capacity, excellent rate capability, and robust cycling stability (729 mAh cm-3 at 15 C after 2000 cycles). Moreover, the as-assembled (SnS)1.15TaS2 || Na3V2(PO4)3 full cells achieve robust and fast Na+ storage performance with ≈100% capacity retention after 650 cycles at 15 C, which also demonstrates good low-temperature performance at -20 °C with a capacity retention of 75% and 2 C high-rate charge/discharge ability.
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Potassium-ion batteries (PIBs) have attracted much attention due to their low production cost and abundant resources. Germanium is a promising alloying-type anode with a high theoretical capacity for PIBs, yet suffering significant volume expansion and sluggish potassium-ion transport kinetics. Herein, a rational strategy is formulated to disperse Ge atoms into transition metal V-S sulfide frameworks to form a loosely packed and metallic GeV4S8 medium. The theoretical prediction shows that GeV4S8 is conducive to the adsorption and diffusion of K+. The V-S frameworks provide fast ion/electron diffusion channels and also help to buffer the volume expansion during K+ insertion. In situ and ex situ characterizations manifest that KGe alloy clusters are constrained and dispersed by potassiated VS2 topological structure during discharging, and revert to the original GeV4S8 after charging. Consequently, as a novel anode for PIBs, GeV4S8 provides a high specific capacity of ≈400 mAh g-1 at 0.5 C, maintaining 160 mAh g-1 even at 12.5 C and ≈80% capacity after 1000 cycles at 5 C, superior to most of the state-of-the-art anode materials. The proposed strategy of combining alloy and intercalation dual-functional units is expected to open up a new way for high-capacity and high-rate anode for PIBs.
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BACKGROUND: Although hepatitis B virus (HBV) infection is a major risk factor for hepatic cancer, the majority of HBV carriers do not develop this lethal disease. Additional molecular alterations are thus implicated in the process of liver tumorigenesis. Since phosphatase and tensin homolog (PTEN) is decreased in approximately half of liver cancers, we investigated the significance of PTEN deficiency in HBV-related hepatocarcinogenesis. METHODS: HBV-positive human liver cancer tissues were checked for PTEN expression. Transgenic HBV, Alb-Cre and Ptenfl/fl mice were inter-crossed to generate WT, HBV, Pten-/- and HBV; Pten-/- mice. Immunoblotting, histological analysis and qRT-PCR were used to study these livers. Gp73-/- mice were then mated with HBV; Pten-/- mice to illustrate the role of hepatic tumor biomarker golgi membrane protein 73 (GP73)/ golgi membrane protein 1 (GOLM1) in hepatic oncogenesis. RESULTS: Pten deletion and HBV transgene synergistically aggravated liver injury, inflammation, fibrosis and development of mixed hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). GP73 was augmented in HBV; Pten-/- livers. Knockout of GP73 blunted the synergistic effect of deficient Pten and transgenic HBV on liver injury, inflammation, fibrosis and cancer development. CONCLUSIONS: This mixed HCC-ICC mouse model mimics liver cancer patients harboring HBV infection and PTEN/AKT signaling pathway alteration. Targeting GP73 is a promising therapeutic strategy for cancer patients with HBV infection and PTEN alteration.
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Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , PTEN Fosfo-Hidrolase , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/patologia , Fibrose , Hepatite B/complicações , Vírus da Hepatite B , Inflamação/patologia , Fígado/patologia , Neoplasias Hepáticas/patologia , Proteínas de Membrana/metabolismo , Camundongos Knockout , PTEN Fosfo-Hidrolase/metabolismoRESUMO
Arable land is facing the growing challenge of land degradation due to intensive use and this is beginning to affect global food security. However, active and passive restoration can improve soil characteristics and reshape microbial communities. Despite the increasing focus on changes in microbial communities during restoration, the mechanisms underlying how microbes drive the soil quality index (SQI) in arable land restoration remain unclear. In this study, we selected conventional farmland (CF, heavily intensified) and two restoration strategies (AR, artificial restoration; NR, natural restoration), with the same context (including soil texture, climate, etc.), and measured the microbial indicators over 2 years to investigate the mechanisms driving SQI improvement on restored arable land. The AR and NR treatments resulted in a 50% and 58% increase in SQI, respectively, compared to CF as soil nutrient levels increased, resulting in higher microbial biomasses and enzyme activities. Microbial abundance on the AR land was approximately two times greater than on the NR land due to the introduction of legumes. Bacterial diversity declined, while fungi developed in a more diverse direction under the restoration strategies. The AR and NR areas were mainly enriched with rhizobium (Microvirga, Bradyrhizobium), which contribute to healthy plant growth. The pathogenic fungi (Gibberella, Fusarium, Volutella) were more abundant in the CF area and the plant pathogen guild was about five times higher in the restored areas. Following arable land restoration, microbial life history strategies shifted from r-to K-strategists due to the higher proportion of recalcitrant SOC (DOC/SOC decreased by 18%-30%). The altered microbial community in the restored areas created new levels of functionality, with a 2.6%-4.3% decrease in bacterial energy metabolism (oxidative phosphorylation, C fixation, and N metabolism decreased by 7%, 4%, and 6%, respectively). Structural equation modelling suggested that restoration strategy affected SQI either directly by increasing total soil nutrient levels or indirectly by altering the microbial community and that fungal community composition and bacterial diversity made the largest contributions to SQI. These results provided new insights into soil quality improvement from a microbial perspective and can help guide future arable land restoration.
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Micobioma , Solo , Bactérias/genética , Plantas , Biomassa , Fungos , Microbiologia do SoloRESUMO
Fasciolosis is a parasitic disease affecting humans and livestock, caused by digenean trematodes of the genus Fasciola, primarily F. hepatica and F. gigantica. This study investigates the coexistence of these species and their hybrids in yaks from Tibet, China. We analyzed the nuclear rDNA internal transcribed spacer (ITS) regions, including ITS1 and ITS2, through Sanger sequencing and Next-Generation Sequencing (NGS) to assess single-nucleotide polymorphisms (SNPs). Our results reveal that one specimen (NM008B) is identical to pure F. hepatica, while another (NM008A) contains genetic information from both F. hepatica and F. gigantica, indicating potential hybridization or introgression. The morphological analysis reveals that the collected adult F. hepatica specimens exhibit distinct characteristics, while the hybrid specimens display "intermediate" features of F. hepatica and F. gigantica. This study is the first to document the coexistence of F. hepatica and hybrid Fasciola forms in a single yak. The findings underscore the complexities of hybridization dynamics and the necessity for advanced molecular techniques in accurately identifying Fasciola species. Future research should focus on mitochondrial DNA and other nuclear gene analysis to further elucidate the nature of these hybrids and their ecological implications.
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Doenças dos Bovinos , DNA Espaçador Ribossômico , Fasciola , Fasciolíase , Animais , Bovinos , Tibet , Fasciola/genética , Fasciola/classificação , Fasciola/isolamento & purificação , Fasciolíase/veterinária , Fasciolíase/parasitologia , Fasciolíase/epidemiologia , DNA Espaçador Ribossômico/genética , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/epidemiologia , DNA de Helmintos/genética , Fasciola hepatica/genética , Fasciola hepatica/classificação , Fasciola hepatica/isolamento & purificação , Análise de Sequência de DNA , Polimorfismo de Nucleotídeo Único , Hibridização Genética , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
The discontinuous interfacial contact of solid-state polymer metal batteries is due to the stress changes in the electrode structure during cycling, resulting in poor ion transport. Herein, a rigid-flexible coupled interface stress modulation strategy is developed to solve the above issues, which is to design a rigid cathode with enhanced solid-solution behavior to guide the uniform distribution of ions and electric field. Meanwhile, the polymer components are optimized to build an organic-inorganic blended flexible interfacial film to relieve the change of interfacial stress and ensure rapid ion transmission. The fabricated battery comprising a Co-modulated P2-type layered cathode (Na0.67Mn2/3Co1/3O2) and a high ion conductive polymer could deliver good cycling stability without distinct capacity fading (72.8 mAh g-1 over 350 cycles at 1 C), outperforming those without Co modulation or interfacial film construction. This work demonstrates a promising rigid-flexible coupled interfacial stress modulation strategy for polymer-metal batteries with excellent cycling stability.
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Interlayer coupling and stacking order play essential roles in shaping the exotic electronic properties of two-dimensional materials. Here, we employ restacked TaS2âa novel transition metal dichalcogenide (TMD) with weak vdW bonding and twisted anglesâto investigate the strain effects of interlayer modulation on the electronic properties. Under pressure, an unexpected transition from metallic to semiconducting-like states occurs. Superconductivity coexists with the semiconducting-like state over a wide pressure range, which has never before been observed in TMDs. Upon further compression, a new superconducting SC-II state emerges without structural evolution and gradually replaces the initial SC-I state. The emerging SC-II state exhibits robust zero-resistance superconductivity and an ultrahigh upper critical field. The abundant electronic state changes in RS-TaS2 are strongly related to band-structure engineering resulting from pressure-induced interlayer stacking angle modulation. Our results reveal the remarkable effect of interlayer rearrangement on electronic properties and provide a special way to explore the unique properties of 2D materials.
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Two-dimensional (2D) van der Waals (vdW) materials, featuring relaxed phase-matching conditions and highly tunable optical nonlinearity, endow them with potential applications in nanoscale nonlinear optical (NLO) devices. Despite significant progress, fundamental questions in 2D NLO materials remain, such as how structural distortion affects second-order NLO properties, which call for advanced regulation and in situ diagnostic tools. Here, by applying pressure to continuously tune the displacement of Nb atoms in 2D vdW NbOI2, we effectively modulate the polarization and achieve a 3-fold boost of the second-harmonic generation (SHG) at 2.5 GPa. By introducing a Peierls distortion parameter, λ, we establish a quantitative relationship between λ and SHG intensity. Importantly, we further demonstrate that the SHG enhancement can be achieved under ambient conditions by anionic substitution to tune the distortion in NbO(I1-xBrx)2 (x = 0-1) compounds, where the chemical tailoring simulates the pressure effects on the structural optimization. Consequently, NbO(I0.60Br0.40)2 with λ = 0.17 exhibits a giant SHG of over 2 orders of magnitude higher than that in monolayer WSe2, reaching the record-high value among reported 2D vdW NLO materials. This work unambiguously demonstrates the correlation between Peierls distortion and SHG property and, more broadly, opens new paths for the development of advanced NLO materials by manipulating the structure distortions.
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Second harmonic generation (SHG) of 2D crystals has been of great interest due to its advantages of phase-matching and easy integration into nanophotonic devices. However, the polarization-dependence character of the SHG signal makes it highly troublesome but necessary to match the laser polarization orientation relative to the crystal, thus achieving the maximum polarized SHG intensity. Here, it is demonstrated a polarization-independent SHG, for the first time, in the van der Waals Nb3 SeI7 crystals with a breathing Kagome lattice. The Nb3 triangular clusters and Janus-structure of each Nb3 SeI7 layer are confirmed by the STEM. Nb3 SeI7 flake shows a strong SHG response due to its noncentrosymmetric crystal structure. More interestingly, the SHG signals of Nb3 SeI7 are independent of the polarization of the excitation light owing to the in-plane isotropic arrangement of nonlinear active units. This work provides the first layered nonlinear optical crystal with the polarization-independent SHG effect, providing new possibilities for nonlinear optics.
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High-capacity metal oxides based on non-toxic earth-abundant elements offer unique opportunities as advanced anodes for lithium-ion batteries (LIBs). But they often suffer from large volumetric expansion, particle pulverization, extensive side reactions, and fast degradations during cycling. Here, an easy synthesis method is reported to construct amorphous borate coating network, which stabilizes conversion-type iron oxide anode for the high-energy-density semi-solid-state bipolar LIBs. The nano-borate coated iron oxide anode has high tap density (1.6 g cm-3 ), high capacity (710 mAh g-1 between 0.5 - 3.0 V, vs Li/Li+ ), good rate performance (200 mAh g-1 at 50 C), and excellent cycling stability (≈100% capacity resention over 1,000 cycles at 5 A g-1 ). When paired with high-voltage cathode LiCoO2 , it enables Cu current collector-free pouch-type classic and bipolar full cells with high voltage (7.6 V with two stack layers), achieving high energy density (≈350 Wh kg-1 ), outstanding power density (≈6,700 W kg-1 ), and extended cycle life (75% capacity retention after 2,000 cycles at 2 C), superior to the state-of-the-art high-power LIBs using Li4 Ti5 O12 anode. The design and methodology of the nanoscale polyanion-like coating can be applied to other metal oxides electrode materials, as well as other electrochemical materials and devices.
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Laser-driven phase transition of 2D transition metal dichalcogenides has attracted much attention due to its high flexibility and rapidity. However, there are some limitations during the laser irradiation process, especially the unsatisfied surface ablation, the inability of nanoscale phase patterning, and the unexploited physical properties of new phase. In this work, the well-controlled femtosecond (fs) laser-driven transformation from the metallic 2M-WS2 to the semiconducting 2H-WS2 is reported, which is confirmed to be a single-crystal to single-crystal transition without layer thinning or obvious ablation. Moreover, a highly ordered 2H/2M nano-periodic phase transition with a resolution of ≈435 nm is achieved, breaking through the existing size bottleneck of laser-driven phase transition, which is attributed to the selective deposition of plasmon energy induced by fs laser. It is also demonstrated that the achieved 2H-WS2 after laser irradiation contains rich sulfur vacancies, which exhibits highly competitive ammonia gas sensing performance, with a detection limit below 0.1 ppm and a fast response/recovery time of 43/67 s at room temperature. This study provides a new strategy for the preparation of the phase-selective transition homojunction and high-performance applications in electronics.
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Sodium manganese-based oxides (NMO) are attracting huge attention as safe and cost-effective cathode materials for sodium-ion batteries (SIBs). To date, one of the most important challenges of NMO-based cathodes is the relatively low capacity. Therefore, it is of great significance to develop high-capacity NMO-based cathodes. Great efforts have been made to enhance the reversible capacity of NMO-based cathodes, achieving considerable progress not only on electrochemical performance, but also the mechanism of massive sodium ion storage. In this paper, the structure and sodium storage mechanism for typical phases of NMO are reviewed, including P2, P3, O3, tunnel-type, and spinel-type NMO-based cathodes. Strategies for high-capacity NMO-based cathodes, such as cationic substitution, anion redox activation, etc are introduced in detail. Last but not least, the future opportunities and challenges for high-capacity NMO-based cathode are prospected.
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Access to new superconducting phases in transition-metal dichalcogenides (TMDs) via pressure treatment has been the primary target in this field. As equally essential as the fabrication of new superconducting materials at high pressure, maneuvering new superconducting phases at moderate pressures is also one of the core goals in the synthesis community. Here, we successfully reduced the synthesized pressure of the superconducting phase in ReSe2 by combining V-doping and high-pressure techniques, with a reduction in pressure of 50% in contrast to ReSe2. Our electrical transport measurements displayed that metallization appeared at 10 GPa and subsequently superconductivity appeared at about 52.4 GPa with Tc â¼ 1.9 K. There was a giant reduction in the stable pressure of the superconducting phase derived from the d-electrons and interlayer interaction changes, as evidenced by the Hall effect and X-ray diffraction measurements. These findings serve as ideal starting points and guidance for designing superconducting TMDs at moderate pressures.
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The quantum spin Hall (QSH) effect has attracted extensive research interest because of the potential applications in spintronics and quantum computing, which is attributable to two conducting edge channels with opposite spin polarization and the quantized electronic conductance of 2e2/h. Recently, 2M-WS2, a new stable phase of transition metal dichalcogenides with a 2M structure showing a layer configuration identical to that of the monolayer 1T' TMDs, was suggested to be a QSH insulator as well as a superconductor with a critical transition temperature of around 8 K. Here, high-resolution angle-resolved photoemission spectroscopy (ARPES) and spin-resolved ARPES are applied to investigate the electronic and spin structure of the topological surface states (TSS) in the superconducting 2M-WS2. The TSS exhibit characteristic spin-momentum-locking behavior, suggesting the existence of long-sought nontrivial Z2 topological states therein. We expect that 2M-WS2 with coexisting superconductivity and TSS might host the promising Majorana bound states.
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BACKGROUND: In 2017, surveillance for tickborne diseases in China led to the identification of a patient who presented to a hospital in Inner Mongolia with a febrile illness that had an unknown cause. The clinical manifestation of the illness was similar to that of tickborne encephalitis virus (TBEV) infection, but neither TBEV RNA nor antibodies against the virus were detected. METHODS: We obtained a blood specimen from the index patient and attempted to isolate and identify a causative pathogen, using genome sequence analysis and electron microscopy. We also initiated a heightened surveillance program in the same hospital to screen for other patients who presented with fever, headache, and a history of tick bites. We used reverse-transcriptase-polymerase-chain-reaction (RT-PCR) and cell-culture assays to detect the pathogen and immunofluorescence and neutralization assays to determine the levels of virus-specific antibodies in serum specimens from the patients. RESULTS: We found that the index patient was infected with a previously unknown segmented RNA virus, which we designated Alongshan virus (ALSV) and which belongs to the jingmenvirus group of the family Flaviviridae. ALSV infection was confirmed by RT-PCR assay in 86 patients from Inner Mongolia and Heilongjiang who presented with fever, headache, and a history of tick bites. Serologic assays showed that seroconversion had occurred in all 19 patients for whom specimens were available from the acute phase and the convalescent phase of the illness. CONCLUSIONS: A newly discovered segmented virus was found to be associated with a febrile illness in northeastern China. (Funded by the National Key Research and Development Program of China and the National Natural Science Foundation of China.).
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Doenças Transmissíveis Emergentes/virologia , Flaviviridae/isolamento & purificação , Doenças Transmitidas por Carrapatos/virologia , Adulto , Idoso , Animais , China/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Fadiga/etiologia , Feminino , Febre/etiologia , Flaviviridae/classificação , Flaviviridae/genética , Flaviviridae/ultraestrutura , Cefaleia/etiologia , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Avaliação de Sintomas , Doenças Transmitidas por Carrapatos/complicações , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/virologiaRESUMO
Lead-free Cs2 AgBiBr6 double perovskite is considered to be a promising alternative to the traditional lead-based analogues due to its long carrier lifetime, high structural stability, and non-toxicity. However, the large band gap limits its absorption of visible light, which is not conducive to further optoelectronic applications. Herein, a thermochromic strategy is reported to decrease the band gap of Cs2 AgBiBr6 by approximately 0.36 eV, obtaining the smallest reported band gap of 1.69 eV under ambient conditions. The experimental data indicate that after annealing the Cs2 AgBiBr6 single crystals at 400 °C, the silver (Ag) and bismuth (Bi) atoms occupy the B-site in a random way and form a partially disordered configuration. The formation of the antisite defects broadens the band edges and decreases the band gap. This work offers new insights into the preparation of narrow band gap lead-free double perovskites, and a deep understanding of their structural and electronic properties for further development in photoelectric devices.
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Polyvinyl chloride (PVC) is widely used in daily life, but its waste has become a serious environmental problem. A solid base assisted low-temperature solvothermal dehalogenation was developed in this work to sustainably and efficiently transform PVC into high-value dimethylamine hydrochloride (DMACl) chemical and N,O co-doped carbon monolith with hierarchically porous structure. The synergistic promotion of solid-base catalyst and solvent decomposition with the removal of HCl can shift forward the chemical equilibrium to promote the dechlorination of PVC and increase the carbon yield. Meanwhile, the solid-base catalyst can also act as a pore-forming additive to fabricate the carbon monolith with hierarchical pores. Induced by the high specific surface area, hierarchical pores and N,O co-doped structure, the generated carbon monolith exhibits superior electrocatalytic performance towards H2 evolution. These discoveries shed light on the design of synergistically coupled solvent and solid catalyst to promote the heterogeneous conversion of waste chlorinated plastics into high-value chemicals for a sustainable future.