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1.
Inorg Chem ; 62(14): 5496-5504, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36976265

RESUMO

We utilized the etb platform of MOFs for the synthesis of two new water-stable compounds based on amide functionalized trigonal tritopic organic linkers H3BTBTB (L1), H3BTCTB (L2) and Al3+ metal ions, namely, Al(L1) and Al(L2). The mesoporous Al(L1) material exhibits an impressive methane (CH4) uptake at high pressures and ambient temperature. The corresponding values of 192 cm3 (STP) cm-3, 0.254 g g-1 at 100 bar, and 298 K are among the highest reported for mesoporous MOFs, while the gravimetric and volumetric working capacities (between 80 bar and 5 bar) can be well compared to the best MOFs for CH4 storage. Furthermore, at 298 K and 50 bar, Al(L1) adsorbs 50 wt % (304 cm3 (STP) cm-3) CO2, values among the best recorded for CO2 storage using porous materials. To gain insight into the mechanism accounting for the resultant enhanced CH4 storage capacity, theoretical calculations were performed, revealing the presence of strong CH4 adsorption sites near the amide groups. Our work demonstrates that amide functionalized mesoporous etb-MOFs can be valuable for the design of versatile coordination compounds with CH4 and CO2 storage capacities comparable to ultra-high surface area microporous MOFs.

2.
Inorg Chem ; 62(49): 20142-20152, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38009949

RESUMO

Chiral hybrid metal-halide semiconductors (MHS) pose as ideal candidates for spintronic applications owing to their strong spin-orbit coupling (SOC), and long spin relaxation times. Shedding light on the underlying structure-property relationships is of paramount importance for the targeted synthesis of materials with an optimum performance. Herein, we report the synthesis and optical properties of 1D chiral (R-/S-THBTD)SbBr5 (THBTD = 4,5,6,7-tetrahydro-benzothiazole-2,6-diamine) semiconductors using a multifunctional ligand as a countercation and a structure directing agent. (R-/S-THBTD)SbBr5 feature direct and indirect band gap characteristics, exhibiting photoluminescence (PL) light emission at RT that is accompanied by a lifetime of a few ns. Circular dichroism (CD), second harmonic generation (SHG), and piezoresponse force microscopy (PFM) studies validate the chiral nature of the synthesized materials. Density functional theory (DFT) calculations revealed a Rashba/Dresselhaus (R/D) spin splitting, supported by an energy splitting (ER) of 23 and 25 meV, and a Rashba parameter (αR) of 0.23 and 0.32 eV·Å for the R and S analogs, respectively. These values are comparable to those of the 3D and 2D perovskite materials. Notably, (S-THBTD)SbBr5 has been air-stable for a year, a record performance among chiral lead-free MHS. This work demonstrates that low-dimensional, lead-free, chiral semiconductors with exceptional air stability can be acquired, without compromising spin splitting and manipulation performance.

3.
Angew Chem Int Ed Engl ; 62(12): e202218429, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36656785

RESUMO

In this work we report a strategy for generating porosity in hybrid metal halide materials using molecular cages that serve as both structure-directing agents and counter-cations. Reaction of the [2.2.2] cryptand (DHS) linker with PbII in acidic media gave rise to the first porous and water-stable 2D metal halide semiconductor (DHS)2 Pb5 Br14 . The corresponding material is stable in water for a year, while gas and vapor-sorption studies revealed that it can selectively and reversibly adsorb H2 O and D2 O at room temperature (RT). Solid-state NMR measurements and DFT calculations verified the incorporation of H2 O and D2 O in the organic linker cavities and shed light on their molecular configuration. In addition to porosity, the material exhibits broad light emission centered at 617 nm with a full width at half-maximum (FWHM) of 284 nm (0.96 eV). The recorded water stability is unparalleled for hybrid metal halide and perovskite materials, while the generation of porosity opens new pathways towards unexplored applications (e.g. solid-state batteries) for this class of hybrid semiconductors.

4.
ACS Appl Mater Interfaces ; 15(36): 42717-42729, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37639320

RESUMO

Hybrid metal halide semiconductors are a unique family of materials with immense potential for numerous applications. For this to materialize, environmental stability and toxicity deficiencies must be simultaneously addressed. We report here a porous, visible light semiconductor, namely, (DHS)Bi2I8 (DHS = [2.2.2] cryptand), which consists of nontoxic, earth-abundant elements, and is water-stable for more than a year. Gas- and vapor-sorption studies revealed that it can selectively and reversibly adsorb H2O and D2O at room temperature (RT) while remaining impervious to N2 and CO2. Solid-state NMR measurements and density functional theory (DFT) calculations verified the incorporation of H2O and D2O in the molecular cages, validating the porous nature. In addition to porosity, the material exhibits broad band-edge light emission centered at 600 nm with a full width at half-maximum (fwhm) of 99 nm, which is maintained after 6 months of immersion in H2O. Moreover, (DHS)Bi2I8 exhibits bacteriocidal action against three Gram-positive and three Gram-negative bacteria, including antibiotic-resistant strains. This performance, coupled with the recorded water stability and porous nature, renders it suitable for a plethora of applications, from solid-state batteries to water purification and disinfection.

5.
Int J Clin Oncol ; 14(3): 230-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19593615

RESUMO

BACKGROUND: This study was conducted using irinotecan and cisplatin (IP) concurrently with thoracic radiation therapy to evaluate the response and toxicity of this protocol in the treatment of patients with limited-disease small cell lung cancer (LD-SCLC). METHODS: Twenty-seven chemotherapy-naive patients with LD-SCLC received two cycles of weekly irinotecan 60 mg/m(2) and cisplatin 60 mg/m(2) before the initiation of the thoracic radiation therapy. RESULTS: Of the 29 patients with LD-SCLC enrolled in the study, 27 were eligible for evaluation of response and toxicity. The median age was 62 years; 26 patients (90%) were men. Eastern Cooperative Oncology Group (ECOG) performance status was 0 in 5 patients (17%) and 1 in 18 patients (62%). Ten patients (37%) achieved a complete response (CR), 14 patients (52%) achieved a partial response (PR), while 3 patients (11%) had progressive disease (PD); one of the 3 nonresponders achieved a PR after commencing concurrent chemoradiotherapy; therefore, the overall response rate was 93%. The median survival time was 20.2 months and 1- and 2-year survival rates were 69% and 53.2%, respectively. The median progression-free survival (PFS) was 11.8 months, and 1- and 2-year PFS times were 52% and 34.1%, respectively. Neutropenia was the most prevalent hematological toxicity and it was evident as grade 3 in 14 patients (52%). Asthenia was the most prevalent nonhematological toxicity, in 18 patients (67%); esophagitis occurred in 15 patients (56%). No treatment-related deaths (due to sepsis or bleeding) were reported in the study. CONCLUSION: Irinotecan and cisplatin is considered to be an effective and safe chemotherapeutic regimen when used concurrently with thoracic radiation therapy for the treatment of patients with LD-SCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Pequenas/terapia , Neoplasias Pulmonares/terapia , Idoso , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Carcinoma de Células Pequenas/mortalidade , Cisplatino/administração & dosagem , Terapia Combinada , Feminino , Humanos , Irinotecano , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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