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1.
Small ; : e2309091, 2024 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-38247184

RESUMEN

Activating the lattice oxygen in the catalysts to participate in the oxygen evolution reaction (OER), which can break the scaling relation-induced overpotential limitation (> 0.37 V) of the adsorbate evolution mechanism, has emerged as a new and highly effective guide to accelerate the OER. However, how to increase the lattice oxygen participation of catalysts during OER remains a major challenge. Herein, P-incorporation induced enhancement of lattice oxygen participation in double perovskite LaNi0.58 Fe0.38 P0.07 O3-σ (PLNFO) is studied. P-incorporation is found to be crucial for enhancing the OER activity. The current density reaches 1.35 mA cmECSA -2 at 1.63 V (vs RHE), achieving a sixfold increase in intrinsic activity. Experimental evidences confirm the dominant lattice oxygen participation mechanism (LOM) for OER pathway on PLNFO. Further electronic structures reveal that P-incorporation shifts the O p-band center by 0.7 eV toward the Fermi level, making the states near the Fermi level more O p character, thus facilitating LOM and fast OER kinetics. This work offers a possible method to develop high-performance double perovskite OER catalysts for electrochemical water splitting.

2.
J Colloid Interface Sci ; 660: 617-627, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266343

RESUMEN

Clean H2 fuel obtained from the photocatalytic water splitting to hydrogen reaction could efficiently alleviate current energy crisis and the concomitant environmental pollution problems. Therefore, it is desirable to search for a highly efficient photocatalytic system to decrease the energy barrier of water splitting reaction. Herein, the 1T/2H mixed phase MoS2 sample with Schottky junction between contact interfaces is developed through molten salt synthesis for photocatalytic hydrogen production under a dye-sensitized system (Eosin Y-TEOA-MoS2) driven by the visible light. In mixed phase MoS2 sample, the photogenerated electrons of 2H-phase MoS2 migrated to the 1T-phase MoS2 are difficult to jump back because of the existence of Schottky barrier, which greatly suppresses the quenching of EY and therefore results in an enhanced hydrogen evolution performance. Therefore, the optimized MoS2 sample (MoS2-350) has an initial hydrogen evolution rate of 213 µmol h-1 and corresponding apparent quantum yield of 36.1 % at 420 nm, far higher than those of pure Eosin Y. It is strongly confirmed by the steady-state/time-resolved photoluminescence (PL) spectra and transient photocurrent response experiments. With the assistance of Density functional theory (DFT) calculation, the function of Schottky junction in photocatalytic hydrogen evolution reaction is well explained. In addition, a new and universal method (SVM curve) of judging oxidation or reduction quenching for photosensitizers is proposed.

3.
Materials (Basel) ; 17(1)2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38203895

RESUMEN

The nonlinear optical properties of carbon dots have been in the spotlight in recent years. In light of the complexity and diversity of factors affecting the nonlinear optical properties of carbon dots, how to reveal the origin and physical mechanism of the nonlinear optical properties of carbon dots accurately has become a problem. In this work, a template-free method was designed to prepare carbon dots via solid-phase reaction with phloroglucinol as a single carbon source and sodium bisulfate as the catalyst. This method is simple, green, safe, and easy to be prepared on a large scale. Three carbon dots with different luminous colors were obtained by simply adjusting the reaction temperature. The rise of reaction temperature affects the surface functional groups, and then hinders the luminescence of surface states, leading to the change of luminescence properties. The nonlinear optical properties of carbon dots were analyzed by the Z-scan technique. Surprisingly, all carbon dots have nonlinear optical responses, but there are differences in performance. Results prove the increase in sp2 domains may contribute to the significant improvement of the nonlinear optical properties of carbon dots, indicating a direction to improve the nonlinear optical properties of carbon dots.

4.
ACS Appl Mater Interfaces ; 12(43): 48982-48990, 2020 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-33074650

RESUMEN

Electrical tuning of the nonlinear absorption of materials has promising application potential, while studies remain rare. In this work, we show that the third-order nonlinear absorption of poly(3,4-ethylenedioxythiophene) chemically doped with poly(styrene sulfonic acid) [PEDOT:PSS] can be effectively modulated by external voltage. The nonlinear absorption of the film can be varied between reverse saturable absorption (RSA) and saturable absorption (SA) via voltage control with laser excitation at 800 nm, and the corresponding nonlinear absorption coefficient can be tuned in the range -1606 ± 73 to 521 ± 9 cm GW-1. The doping level and energy structure of PEDOT are modulated with different voltages. The undoped film affords two-photon absorption and accordingly the RSA response. A moderately doped sample has two polaron levels, and Pauli blocking associated with these two polaron levels results in SA. The bipolaron level in heavily doped PEDOT leads to excited-state absorption and therefore RSA behavior. The approach reported here can be applied to other semiconductors and is a convenient, effective, and promising method for the electrical tuning of the optical nonlinearity.

5.
ACS Appl Mater Interfaces ; 12(6): 7423-7431, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31967773

RESUMEN

We synthesize a vertical heterostructure (HS) between tin sulfide (SnS) and molybdenum sulfide (MoS2) by chemical vapor deposition based on the preferential adsorption of sulfur on MoS2. Most of the SnS grains nucleate on MoS2 nanosheets, formatting partially stacked HS with large overlapping regions. Photoluminescence quenching of MoS2 is observed and illustrates effective charge separation in HS. The HS shows increased reverse saturable absorption relative to MoS2 and SnS. The preferential adsorption of sulfur powders on MoS2 and HS growth reported herein will provide a promising approach to the synthesis of other two-dimensional HS.

6.
ACS Appl Mater Interfaces ; 11(39): 35835-35844, 2019 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-31486331

RESUMEN

The construction of p-n junctions is necessitated by applications which require effective charge separation. Here, a novel heterostructure (HS) of molybdenum sulfide (MoS2) and copper sulfide (Cu2-xS) was synthesized by chemical vapor deposition, with Cu2-xS nanoparticles vertically stacked on a MoS2 nanosheet. A well-defined epitaxial relationship between MoS2 and Cu2-xS is established, although the corresponding lattice mismatch is as large as 20%. The band-edge alignment is experimentally determined, indicating that the MoS2-Cu2-xS HS is a type II heterojunction. Photoluminescence quenching indicates effective charge separation in HS. The resultant HS shows enhanced nonlinear absorption in comparison with single-component MoS2 nanosheets and Cu2-xS nanoparticles.

7.
Urology ; 132: 164-169, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31279692

RESUMEN

OBJECTIVE: To evaluate the impact of photoselective vaporization of the prostate (PVP) on erectile function (EF) utilizing a 160W GreenLight laser system with up to 36 months of follow-up in men with lower urinary tract symptoms caused by benign prostatic hyperplasia. METHODS: A prospectively maintained database of patients who underwent GreenLight PVP was retrospectively reviewed. International Index of Erectile Function-5 (IIEF-5) questionnaire was used to assess EF. In total, 265 sexually active patients who underwent 160W GreenLight laser PVP were identified and divided into Group A with baseline IIEF-5 <19 and group B with baseline IIEF-5 ≥19. IIEF-5, International Prostate Symptom Score, quality of life, postvoid residual, and Qmax were recorded preoperatively, perioperatively, and at follow-up after 1, 3, 6, 12, 24, and 36 months. Recorded data were analyzed statistically using t- and χ2 tests. RESULTS: The preoperative and perioperative data of the 2 groups were comparable. Significant improvements in International Prostate Symptom Score, Qmax, quality of life, and postvoid residual were observed in both groups at every follow-up visit throughout the 36 months with no significant difference between the groups. EF was sustained postoperatively compared with the baseline in the whole study population. In Group A (preoperative IIEF-5 <19), EF was significantly improved at 1 month and 12 month (P= .02 and P= .002). CONCLUSION: In patients undergoing PVP by 160W GreenLight laser for lower urinary tract symptoms secondary to benign prostatic hyperplasia, no significant detrimental effect was observed in the EF at up to 3 years of follow-up. However, in patients with preoperative erectile dysfunction (ED), we showed a significant improvement.


Asunto(s)
Síntomas del Sistema Urinario Inferior/cirugía , Erección Peniana , Hiperplasia Prostática/cirugía , Resección Transuretral de la Próstata , Anciano , Humanos , Síntomas del Sistema Urinario Inferior/etiología , Masculino , Periodo Posoperatorio , Hiperplasia Prostática/complicaciones , Estudios Retrospectivos , Resultado del Tratamiento
8.
Medicine (Baltimore) ; 97(19): e0687, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29742714

RESUMEN

RATIONALE: Clear cell renal cell carcinoma (CCRCC) is an aggressive tumor associated with a high risk of metastasis and very low survival rate. In addition, it can cause extensive blood metastasis to the lungs, bones, and other organs. Chest wall metastatic tumors from primary CCRCC are rare. PATIENT CONCERNS: In this report, we present a case of metastatic chest wall tumor that originated from a CCRCC. DIAGNOSES: An 86-year-old man was diagnosed with chest wall tumor using chest computed tomography. After collecting tissues from the chest wall tumor via needle biopsy, the pathological examination was combined with positive immunoreaction of CD10, epithelial membrane antigen, and vimentin, and the patient was diagnosed with metastatic CCRCC in the chest wall deposits. INTERVENTIONS: The patient received radiotherapy at 2.0 Gy per time for 25 times. OUTCOMES: Following 2 months of treatment, the chest wall tumor had shrunk by about one-third of its size. LESSONS: Our patient developed a metastatic chest wall tumor that originated from a CCRCC for which right nephrectomy had been performed 10 years previously. Although as per the literature, chest wall metastasis from CCRCC is very rare, it is important to consider tumor metastasis after several years of treatment for precise diagnosis and proper treatment.


Asunto(s)
Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Neoplasias Torácicas/secundario , Pared Torácica/patología , Anciano de 80 o más Años , Carcinoma de Células Renales/cirugía , Humanos , Neoplasias Renales/cirugía , Masculino , Nefrectomía , Neoplasias Torácicas/radioterapia , Factores de Tiempo
9.
Urol Int ; 95(3): 269-75, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26138113

RESUMEN

INTRODUCTION: This study investigated the clinical efficacy and safety of photoselective vaporization of the prostate (PVP) and simultaneous suprapubic cystostomy for benign prostatic hyperplasia (BPH) in patients with mild to severe detrusor underactivity (DU). SUBJECTS AND METHODS: Seventy-eight patients with BPH were divided into 3 groups according to the severity of DU: mild DU group, moderate DU group and severe DU group. The preoperative and postoperative data, including the detrusor pressure at maximum flow (Pdetmax), bladder compliance, maximum urinary flow (Qmax), postvoid residual urine (PVR) values, International Prostate Symptom Score (IPSS) and quality of life (QoL) were evaluated. RESULTS: The therapeutic effectiveness including cure and improvement in mild and moderate DU group was significantly higher than that of the severe group. Compared to the preoperative values, Pdetmax, bladder compliance, Qmax, PVR, IPSS and QoL scores at 12 months postoperatively had significantly improved. In addition, the above parameters at 12 months postoperatively in the mild or moderate DU group had significant difference compared to the severe DU group. CONCLUSION: PVP and simultaneous suprapubic cystostomy seem to be an appropriate treatment modality in BPH patients with mild and/or moderate DU as well as in patients with severe DU and slightly reduced bladder compliance.


Asunto(s)
Cistostomía/métodos , Terapia por Láser , Prostatectomía/métodos , Hiperplasia Prostática/cirugía , Enfermedades de la Vejiga Urinaria/cirugía , Anciano , Humanos , Masculino , Hiperplasia Prostática/complicaciones , Índice de Severidad de la Enfermedad , Enfermedades de la Vejiga Urinaria/complicaciones
10.
Int Urol Nephrol ; 46(4): 691-4, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24097277

RESUMEN

PURPOSE: We compared the safety and efficacy of simultaneous transurethral GreenLight photoselective vaporization of bladder tumor and prostate (PVBT/PVP) in patients with bladder tumor and bladder outlet obstruction caused by benign prostate hyperplasia (BPH). METHODS: Sixty-two patients with bladder tumor were enrolled in our prospective and randomized trial. A total of 37 men underwent simultaneous transurethral PVBT/PVP, and 25 patients underwent PVBT alone. The clinicopathological parameters and the recurrence of bladder tumor on the bladder neck/prostatic fossa were evaluated in all patients. RESULTS: Clinicopathological parameters of both groups were similar. The rates of recurrence, progression and tumor recurrence of bladder neck/prostatic fossa were 16.0, 4.0 and 4.0 % in the simultaneous resection group, and 18.9, 5.4 and 8.1 % in the group PVBT, respectively. No statistically significant differences were found between the two groups (P > 0.05). CONCLUSIONS: Simultaneous PVBT/PVP may help decrease the overall recurrence rate and tumor recurrence in bladder neck/prostatic fossa. PVBT/PVP can be performed effectively and safely in patients with bladder tumor and BPH.


Asunto(s)
Terapia por Láser , Síntomas del Sistema Urinario Inferior/cirugía , Recurrencia Local de Neoplasia/prevención & control , Hiperplasia Prostática/cirugía , Obstrucción del Cuello de la Vejiga Urinaria/cirugía , Neoplasias de la Vejiga Urinaria/cirugía , Anciano , Progresión de la Enfermedad , Humanos , Terapia por Láser/efectos adversos , Terapia por Láser/métodos , Síntomas del Sistema Urinario Inferior/etiología , Síntomas del Sistema Urinario Inferior/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Hiperplasia Prostática/complicaciones , Obstrucción del Cuello de la Vejiga Urinaria/etiología , Obstrucción del Cuello de la Vejiga Urinaria/fisiopatología , Neoplasias de la Vejiga Urinaria/complicaciones , Urodinámica
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