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1.
FASEB J ; 37(3): e22824, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36809539

RESUMO

The present study investigated the effects of 2'-5' oligoadenylate synthetase-like (OASL) on the biological functions of stomach adenocarcinoma (STAD) cells and tumor formation in nude mice. The differential expression levels of OASL in the different cancer types from TCGA dataset were analyzed using gene expression profiling interactive analysis. Overall survival and the receiver operating characteristic were analyzed using the KM plotter and R, respectively. Furthermore, OASL expression and its effects on the biological functions of STAD cells were detected. The possible upstream transcription factors of OASL were predicted using JASPAR. The downstream signaling pathways of OASL were analyzed using GSEA. Tumor formation experiments were performed to evaluate the effect of OASL on tumor formation in nude mice. The results showed that OASL was highly expressed in STAD tissues and cell lines. OASL knockdown markedly inhibited cell viability, proliferation, migration, and invasion and accelerated STAD cell apoptosis. Conversely, OASL overexpression had the opposite effect on STAD cells. JASPAR analysis revealed that STAT1 is an upstream transcription factor of OASL. Furthermore, GSEA showed that OASL activated the mTORC1 signaling pathway in STAD. The protein expression levels of p-mTOR and p-RPS6KB1 were suppressed by OASL knockdown and promoted by OASL overexpression. The mTOR inhibitor, rapamycin, markedly reversed the effect of OASL overexpression on STAD cells. Additionally, OASL promoted tumor formation and increased tumor weight and volume in vivo. In conclusion, OASL knockdown suppressed the proliferation, migration, invasion, and tumor formation of STAD cells by inhibiting the mTOR signaling pathway.


Assuntos
2',5'-Oligoadenilato Sintetase , Adenocarcinoma , Neoplasias Gástricas , Animais , Camundongos , Adenocarcinoma/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos Nus , Transdução de Sinais , Neoplasias Gástricas/genética , Serina-Treonina Quinases TOR/metabolismo , 2',5'-Oligoadenilato Sintetase/genética
2.
Drug Resist Updat ; 68: 100936, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36764075

RESUMO

AIMS: Long non-coding RNAs (lncRNAs), as one of the components of exosomes derived from cancer-associated fibroblasts (CAFs), exhibit a crucial role in the pathogenesis and chemoresistance of gastric cancer (GC). Herein, we investigated the role and mechanism of a novel lncRNA disheveled binding antagonist of beta catenin3 antisense1 (DACT3-AS1) and its involvement in GC. METHODS: DACT3-AS1 was identified by RNA-sequencing and verified by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The functional role of DACT3-AS1 in GC was evaluated using in vitro and in vivo experiments including Transwell assay, 5-Ethynyl-2'-deoxyuridine (EdU) assay, immunoblotting, and xenograft tumor mouse model. Dual-luciferase reporter assay was performed to assess the association between genes. RESULTS: DACT3-AS1 was downregulated and involved in poor prognosis of patients with GC. The results from both in vitro and in vivo experiments showed that DACT3-AS1 suppressed cell proliferation, migration, and invasion through targeting miR-181a-5p/sirtuin 1 (SIRT1) axis. Additionally, DACT3-AS1 was transmitted from CAFs to GC cells mainly via exosomes. Exosomal DACT3-AS1 alleviated xenograft tumor growth. DACT3-AS1 conferred sensitivity of cancer cells to oxaliplatin through SIRT1-mediated ferroptosis both in vitro and in vivo. CONCLUSIONS: CAFs-derived exosomal DACT3-AS1 is a suppressive regulator in malignant transformation and oxaliplatin resistance. DACT3-AS1 could be used for diagnosis and treatment of GC.


Assuntos
Fibroblastos Associados a Câncer , Ferroptose , MicroRNAs , Neoplasias Gástricas , Humanos , Camundongos , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Oxaliplatina/farmacologia , Oxaliplatina/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Ferroptose/genética , Sirtuína 1/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Transformação Celular Neoplásica , Proliferação de Células , Linhagem Celular Tumoral , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
3.
Small ; 16(47): e2004583, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33111466

RESUMO

Recently, single-atom catalysts have aroused extensive attention in fields of clean energy and environmental protection due to their unique activity and efficient utilization of the active atoms. It is of great importance but still remains a great challenge to unveil the effect of single atoms on precise catalysis. Herein, it is reported that doping TiO2 hollow microspheres (TiO2 -HMSs) with single atomic Fe can boost the photoreactivity of TiO2 -HMSs towards NO oxidation due to the synergistic effects of atomically dispersed Fe and bonded Ti atom which act as dual active sites. The atomically dispersed Fe atoms occupy the subsurface Ti vacancies, and the interaction between Ti 3d and Fe 3d orbitals result in the formation of FeTi bond. Single atomic Fe modulates the electronic structure of the bonded Ti atoms by electron transfer, which facilitates the adsorption and activation of NO and O2 at Fe and bonded Ti sites, respectively. In addition, the introduction of single atomic Fe sharply suppresses the production of toxic NO2 byproduct. The synergistic effects of the dual active sites then cause a drastic promotion in photocatalytic oxidation of NO.

4.
Inorg Chem ; 59(2): 976-979, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31885252

RESUMO

Quasi-one-dimensional (Q1D) semiconductor materials, such as carbon nanotubes, SbSI, MP15 (M = Li, Na, K), and selenium and tellurium nanowires, show amazing potential for applications in future nanoelectronic and optoelectronic devices. However, intricate chirality in the structure of carbon nanotubes limits their applications. Also, the performance of MP15 in optoelectronics has yet to be extensively explored. One new Q1D semiconductor material, fibrous phosphorus (FP), has recently received attention because its raw material is less toxic. However, the ability to characterize FP by phase identification is limited in the assessment of micro/nano-thickness, such as exfibrated FP. So, identifying a precise Raman spectrum will allow for much better characterization. Here, a sufficiently sharp Raman spectrum of FP was obtained and analyzed. Moreover, we demonstrated that high-quality, few-layer FP fibers with thicknesses as low as 5.55 nm can be produced by liquid-phase exfibration under ambient conditions in solvents. More importantly, an optoelectronic detector based on a single FP fiber field-effect-transistor configuration was investigated. A rise time as short as about 40 ms was obtained for the FP transistors, illustrating the potential of FP single bundle crystals as a new one-dimensional material for optoelectronic device applications.

5.
Exp Gerontol ; 193: 112467, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38797287

RESUMO

OBJECTIVE: To investigate the cognitive function and nutritional status of elderly patients with gastric cancer during perioperative period, and to analyze their correlation. METHODS: Aged patients undergoing gastric cancer surgery in The Affiliated Cancer Hospital of Shandong First Medical University from March to October 2021 were selected as the subjects of this study. The monitoring data of cognitive function and nutritional status were retrospectively analyzed from 1 to 3 days before surgery, 1 and 3 days after surgery, 7 days after surgery (before discharge) and 30 days after surgery to analyze the correlation between cognitive function and nutritional status in elderly patients with gastric cancer. RESULTS: the incidence of mild cognitive impairment in elderly patients with gastric cancer was 52.43 %, the visual space of the two groups' (mild cognitive impairment) ability of execution, name, attention, language, abstract thinking, delayed memory and cognitive function scores were lower than 1 set of directional force (cognitive function in normal group), statistically significant difference (P < 0.05). The nutritional status of elderly patients with gastric cancer was lower than that of healthy elderly group at the same period (P < 0.05). The scores of visual spatial executive function, name, attention, delayed memory, orientation and total score of cognitive function in elderly gastric cancer patients were positively correlated with nutritional status (P < 0.05). CONCLUSIONS: The cognitive function and nutritional status of elderly patients with gastric cancer are both in a low state during treatment and a higher level of cognitive function can help patients maintain a more correct nutritional cognition, and the nutritional status of patients will be relatively better. There is a positive correlation between cognitive function and nutritional status in elderly patients with gastric cancer, which should be paid attention to in the treatment.


Assuntos
Cognição , Disfunção Cognitiva , Estado Nutricional , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/psicologia , Feminino , Masculino , Idoso , Estudos Retrospectivos , Disfunção Cognitiva/etiologia , Período Perioperatório , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade
6.
Redox Biol ; 70: 103051, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38301594

RESUMO

The significant regulatory role of palmitoylation modification in cancer-related targets has been demonstrated previously. However, the biological functions of Nrf2 in stomach cancer and whether the presence of Nrf2 palmitoylation affects gastric cancer (GC) progression and its treatment have not been reported. Several public datasets were used to look into the possible link between the amount of palmitoylated Nrf2 and the progression and its outcome of GC in patients. The palmitoylated Nrf2 levels in tumoral and peritumoral tissues from GC patients were also evaluated. Both loss-of-function and gain-of-function via transgenic experiments were performed to study the effects of palmitoylated Nrf2 on carcinogenesis and the pharmacological function of 2-bromopalmitate (2-BP) on the suppression of GC progression in vitro and in vitro. We discovered that Nrf2 was palmitoylated in the cytoplasmic domain, and this lipid posttranslational modification causes Nrf2 stabilization by inhibiting ubiquitination, delaying Nrf2 destruction via the proteasome and boosting nuclear translocation. Importantly, we also identify palmitoyltransferase zinc finger DHHC-type palmitoyltransferase 2 (DHHC2) as the primary acetyltransferase required for the palmitoylated Nrf2 and indicate that the suppression of Nrf2 palmitoylation via 2-bromopalmitate (2-BP), or the knockdown of DHHC2, promotes anti-cancer immunity in vitro and in mice model-bearing xenografts. Of note, based on the antineoplastic mechanism of 2-BP, a novel anti-tumor drug delivery system ground 2-BP and oxaliplatin (OXA) dual-loading gold nanorods (GNRs) with tumor cell membrane coating biomimetic nanoparticles (CM@GNRs-BO) was established. In situ photothermal therapy is done using near-infrared (NIR) laser irradiation to help release high-temperature-triggered drugs from the CM@GNRs-BO reservoir when needed. This is done to achieve photothermal/chemical synergistic therapy. Our findings show the influence and linkage of palmitoylated Nrf2 with tumoral and peritumoral tissues in GC patients, the underlying mechanism of palmitoylated Nrf2 in GC progression, and novel possible techniques for addressing Nrf2-associated immune evasion in cancer growth. Furthermore, the bionic nanomedicine developed by us has the characteristics of dual drugs delivery, homologous tumor targeting, and photothermal and chemical synergistic therapy, and is expected to become a potential platform for cancer treatment.


Assuntos
Antineoplásicos , Carcinoma , Nanopartículas , Neoplasias Gástricas , Animais , Camundongos , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Fator 2 Relacionado a NF-E2/genética , Biônica , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Nanopartículas/química , Aciltransferases/genética , Aciltransferases/metabolismo
7.
Pathol Res Pract ; 254: 155095, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38237399

RESUMO

BACKGROUND: To explore the role of Kelch repeat and BTB (POZ) domain containing 2 (KBTBD2) in Gastric cancer(GC) via studying the level of KBTBD2 and its impact on GC cells and mice model. METHODS: Expression of KBTBD2 in GC was analyzed by analysis of TCGA data, Western blotting and Real-time quantitative polymerasechain reaction (RT-qPCR). The role of KBTBD2 on GC cells proliferation, viability, invasion, migration and apoptosis in vitro were assessed by using western blotting,RT-qPCR,CCK-8, EDU, Colony Formation Assay, Wound healing assay, Transwell, JC-1 mitochondrial membrane potential and flow cytometry assay, respectively. And levels of Bcl-2, BAX, PARP, E-cadherin, Vimentin, N-cadherin, EGFR, SOS1, NROS, BRAF,ERK1/2 and GAPDH were tested by western blotting. Relation of KBTBD2 and epidermal growth factor receptor (EGFR) was predicted by KEGG analysis. KBTBD2 gene GSEA enrichment was analyzed by using R language. Moreover, CCK-8, western blotting, and wound healing assays were used to verify the correlation of KBTBD2 and EGFR pathway. Finally, tumor growth in mice was also investigated. Cells proliferation, migration and apoptosis were detected by Ki67 staining, Tunnel staining and mouse lung metastasis model. RESULTS: KBTBD2 was highly expressed in GC, and was related to poor prognosis. Moreover, silencing KBTBD2 suppressed GC cell proliferation, migration and invasion, while also inhibited the EMT, but promoted apoptosis. At the same time, KBTBD2 overexpression showed opposite results. In addition, KBTBD2 regulated the EGFR pathway. Further, silencing KBTBD2 inhibited tumor growth, cell proliferation and migration but promoted apoptosis in vivo, and KBTBD2 overexpression showed opposite results. CONCLUSIONS: KBTBD2 was highly expressed in GC. KBTBD2 promotes the progress of GC by activating EGFR signal pathway. KBTBD2 may thus be a novel target for treating GC.


Assuntos
Neoplasias Gástricas , Animais , Camundongos , Neoplasias Gástricas/patologia , Sincalida/genética , Sincalida/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais , Receptores ErbB/genética , Proliferação de Células/genética , Modelos Animais de Doenças , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica
8.
Nat Commun ; 14(1): 2985, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225691

RESUMO

Gastric signet ring cell carcinoma (GSRC) is a special subtype of gastric cancer (GC) associated with poor prognosis, but an in-depth and systematic study of GSRC is lacking. Here, we perform single-cell RNA sequencing to assess GC samples. We identify signet ring cell carcinoma (SRCC) cells. Microseminoprotein-beta (MSMB) can be used as a marker gene to guide the identification of moderately/poorly differentiated adenocarcinoma and signet ring cell carcinoma (SRCC). The upregulated differentially expressed genes in SRCC cells are mainly enriched in abnormally activated cancer-related signalling pathways and immune response signalling pathways. SRCC cells are also significantly enriched in mitogen-activated protein kinase and oestrogen signalling pathways, which can interact and promote each other in a positive feedback loop. SRCC cells are shown to have lower cell adhesion and higher immune evasion capabilities as well as an immunosuppressive microenvironment, which may be closely associated with the relatively poor prognosis of GSRC. In summary, GSRC exhibits unique cytological characteristics and a unique immune microenvironment, which may be advantageous for accurate diagnosis and treatment.


Assuntos
Adenocarcinoma , Carcinoma de Células em Anel de Sinete , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Carcinoma de Células em Anel de Sinete/genética , Análise de Célula Única , Microambiente Tumoral/genética
9.
Nat Commun ; 14(1): 3596, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37328475

RESUMO

The interfacial morphology of crystalline silicon/hydrogenated amorphous silicon (c-Si/a-Si:H) is a key success factor to approach the theoretical efficiency of Si-based solar cells, especially Si heterojunction technology. The unexpected crystalline silicon epitaxial growth and interfacial nanotwins formation remain a challenging issue for silicon heterojunction technology. Here, we design a hybrid interface by tuning pyramid apex-angle to improve c-Si/a-Si:H interfacial morphology in silicon solar cells. The pyramid apex-angle (slightly smaller than 70.53°) consists of hybrid (111)0.9/(011)0.1 c-Si planes, rather than pure (111) planes in conventional texture pyramid. Employing microsecond-long low-temperature (500 K) molecular dynamic simulations, the hybrid (111)/(011) plane prevents from both c-Si epitaxial growth and nanotwin formation. More importantly, given there is not any additional industrial preparation process, the hybrid c-Si plane could improve c-Si/a-Si:H interfacial morphology for a-Si passivated contacts technique, and wide-applied for all silicon-based solar cells as well.


Assuntos
Temperatura Baixa , Silício , Cristalização , Indústrias , Simulação de Dinâmica Molecular
10.
ACS Appl Mater Interfaces ; 14(5): 7513-7521, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35077150

RESUMO

Cognizing the structural characteristics of a heterointerface is significant to understand the growth mechanism of heterostructured nanowires. Here, the structural characteristics of a heterointerface in GaAs-GaAsSb heterostructured nanowires were investigated by employing spherical aberration (CS)-corrected transmission electron microscopy (TEM). It is found that some unusual dislocations are formed at the heterointerface, leading to the bending of nanowires. Further, the atomically inhomogeneous distribution of Sb content near the heterointerface is revealed, which is responsible for the formation of dislocations. By applying a thermal electric system equipped in the Cs-corrected TEM, a direct observation of structural evolution at the heterointerface was enabled and the stability of GaAs-GaAsSb heterostructured nanowires was evaluated. In situ high-resolution TEM imaging indicates that the destabilization of the heterointerface occurs during nanowire annealing. This study builds a direct correlation between the nanowire heterointerfacial structure with nanowire growth behavior and its stability, which is of importance for heterostructured nanowire design for practical use.

11.
Front Oncol ; 11: 709511, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336697

RESUMO

BACKGROUND: Gastric cancer (GC) is one of the most common causes of malignant tumors in the world. Due to the high heterogeneity of GC and lack of specificity of available chemotherapy regimens, these tumors are prone to resistance, recurrence, and metastasis. Here, we formulated an individualized chemotherapy regimen for GC using a modified individual conditional reprogramming (i-CR) system. We established a primary tumor cell bank of GC cells and completed drug screening in order to realize individualized and accurate GC treatment. METHODS: We collected specimens from 93 surgical or gastroscopy GC cases and established a primary tumor cell bank using the i-CR system and PDX models. We also completed in vitro culture and drug sensitivity screening of the GC cells using the i-CR system. Whole-exome sequencing (WES) of the i-CR cells was performed using P0 and P5. We then chose targeted chemotherapy drugs based on the i-CR system results. RESULTS: Of the 72 cases that were collected from surgical specimens, 26 cases were successfully cultured with i-CR system, and of the 21 cases collected from gastroscopy specimens, seven were successfully cultured. Among these, 20 cases of the PDX model were established. SRC ± G3 had the highest culture success rate. The i-CR cells of P0 and P5 appeared to be highly conserved. According to drug sensitivity screening, we examined the predictive value of responses of GC patients to chemotherapeutic agents, especially in neoadjuvant patients. CONCLUSION: The i-CR system does not only represent the growth characteristics of tumors in vivo, but also provides support for clinical drug use. Drug susceptibility results were relatively consistent with clinical efficacy.

12.
Natl Sci Rev ; 8(7): nwaa204, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34691685

RESUMO

Hollow nanoparticles with large specific surface area and high atom utilization are promising catalysts for the hydrogen evolution reaction (HER). We describe herein the design and synthesis of a series of ultra-small hollow ternary alloy nanostructures using a simple one-pot strategy. The same technique was demonstrated for hollow PtNiCu nanoparticles, hollow PtCoCu nanoparticles and hollow CuNiCo nanoparticles. During synthesis, the displacement reaction and oxidative etching played important roles in the formation of hollow structures. Moreover, our hollow PtNiCu and PtCoCu nanoparticles were single crystalline, with an average diameter of 5 nm. Impressively, ultra-small hollow PtNiCu nanoparticles, containing only 10% Pt, exhibited greater electrocatalytic HER activity and stability than a commercial Pt/C catalyst. The overpotential of hollow PtNiCu nanoparticles at 10 mA cm-2 was 28 mV versus reversible hydrogen electrode (RHE). The mass activity was 4.54 A mgPt -1 at -70 mV versus RHE, which is 5.62-fold greater than that of a commercial Pt/C system (0.81 A mgPt -1). Through analyses of bonding and antibonding orbital filling, density functional theory calculations demonstrated that the bonding strength of different metals to the hydrogen intermediate (H*) was in the order of Pt > Co > Ni > Cu. The excellent HER performance of our hollow PtNiCu nanoparticles derives from moderately synergistic interactions between the three metals and H*. This work demonstrates a new strategy for the design of low-cost and high-activity HER catalysts.

13.
Nat Commun ; 12(1): 2473, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931644

RESUMO

Programmable magnetic field-free manipulation of perpendicular magnetization switching is essential for the development of ultralow-power spintronic devices. However, the magnetization in a centrosymmetric single-layer ferromagnetic film cannot be switched directly by passing an electrical current in itself. Here, we demonstrate a repeatable bulk spin-orbit torque (SOT) switching of the perpendicularly magnetized CoPt alloy single-layer films by introducing a composition gradient in the thickness direction to break the inversion symmetry. Experimental results reveal that the bulk SOT-induced effective field on the domain walls leads to the domain walls motion and magnetization switching. Moreover, magnetic field-free perpendicular magnetization switching caused by SOT and its switching polarity (clockwise or counterclockwise) can be reversibly controlled in the IrMn/Co/Ru/CoPt heterojunctions based on the exchange bias and interlayer exchange coupling. This unique composition gradient approach accompanied with electrically controllable SOT magnetization switching provides a promising strategy to access energy-efficient control of memory and logic devices.

14.
Adv Mater ; 33(13): e2003327, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33615589

RESUMO

The platinum single-atom-catalyst is verified as a very successful route to approach the size limit of Pt catalysts, while how to further improve the catalytic efficiency of Pt is a fundamental scientific question and is challenging because the size issue of Pt is approached at the ultimate ceiling as single atoms. Here, a new route for further improving Pt catalytic efficiency by cobalt (Co) and Pt dual-single-atoms on titanium dioxide (TiO2 ) surfaces, which contains a fraction of nonbonding oxygen-coordinated Co-O-Pt dimers, is reported. These Co-Pt dimer sites originate from loading high-density Pt single-atoms and Co single-atoms, with them anchoring randomly on the TiO2 substrate. This dual-single-atom catalyst yields 13.4% dimer sites and exhibits an ultrahigh and stable photocatalytic activity with a rate of 43.467 mmol g-1 h-1 and external quantum efficiency of ≈83.4% at 365 nm. This activity far exceeds those of equal amounts of Pt single-atom and typical Pt clustered catalysts by 1.92 and 1.64 times, respectively. The enhancement mechanism relies on the oxygen-coordinated Co-O-Pt dimer coupling, which can mutually optimize the electronic states of both Pt and Co sites to weaken H* binding. Namely, the "mute" Co single-atom is activated by Pt single-atom and the activity of the Pt atom is further enhanced through the dimer interaction. This strategy of nonbonding interactive dimer sites and the oxygen-mediated catalytic mechanisms provide emerging rich opportunities for greatly improving the catalytic efficiency and developing novel catalysts with creating new electronic states.

15.
ACS Appl Mater Interfaces ; 12(20): 22853-22861, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32337968

RESUMO

Numerous trap states and low conductivity of compact TiO2 layers are major obstacles for achieving high power conversion efficiency and high-stability perovskite solar cells. Here we report an effective Na2S-doped TiO2 layer, which can improve the conductivity of TiO2 layers, the contact of the TiO2/perovskite interface, and the crystallinity of perovskite layers. Comprehensive investigations demonstrate that Na cations increase the conductivity of TiO2 layers while S anions change the wettability of TiO2 layers, thus improving the crystallinity of perovskite layers and passivate defects at the TiO2/PVK interface. The synergetic effects of dopants lead to a champion efficiency as high as 21.25% in unencapsulated perovskite solar cells (PSCs), with much-improved stability. Our work provides new insights on anion dopants in TiO2 layers, which is usually neglected in previous reports, and also proposes a simple approach to produce low-cost and high-performance electron transport layers for high-performance PSCs.

16.
ACS Appl Bio Mater ; 2(1): 488-494, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35016312

RESUMO

Cellulose immobilized palladium (0) nanoparticles (PdNPs) were prepared for the use in scalable catalytic reactions in flow. Preparation of the catalyst is remarkably simple and fast, where a palladium acetate solution is drop-casted onto cellulose paper and then exposed to 1 atm of hydrogen for a mere 90 s to produce embedded Pd(0) nanoparticles. This catalyst system is efficient in the hydrogenation of alkenes, nitroarenes, ketones, and enamides, with products formed in high yields, under ambient pressure and temperature. The system is also effective for transfer hydrogenation using ammonium formate as an alternative hydrogen source. A high catalyst stability and reusability are demonstrated along with the chemoselective and scalable synthesis of industrially important fine chemicals, including the biobased molecule cyrene.

17.
Chem Sci ; 9(37): 7376-7389, 2018 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-30542541

RESUMO

In this study, we, for the first time, report a high Cu solubility of 11.8% in single crystal SnSe microbelts synthesized via a facile solvothermal route. The pellets sintered from these heavily Cu-doped microbelts show a high power factor of 5.57 µW cm-1 K-2 and low thermal conductivity of 0.32 W m-1 K-1 at 823 K, contributing to a high peak ZT of ∼1.41. Through a combination of detailed structural and chemical characterizations, we found that with increasing the Cu doping level, the morphology of the synthesized Sn1-x Cu x Se (x is from 0 to 0.118) transfers from rectangular microplate to microbelt. The high electrical transport performance comes from the obtained Cu+ doped state, and the intensive crystal imperfections such as dislocations, lattice distortions, and strains, play key roles in keeping low thermal conductivity. This study fills in the gaps of the existing knowledge concerning the doping mechanisms of Cu in SnSe systems, and provides a new strategy to achieve high thermoelectric performance in SnSe-based thermoelectric materials.

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