98%
921
2 minutes
20
Pd-TiO2/C catalysts were prepared by impregnating titanium dioxide (TiO2) on carbon-supported Pd (Pd/C) for use as the catalyst for the oxygen reduction reaction (ORR) in direct methanol fuel cells (DMFCs). Transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses were carried to confirm the distribution, morphology and structure of Pd and TiO2 on the carbon support. In fuel cell test, we confirmed that the addition of TiO2 nanoparticles make the improved catalytic activity of oxygen reduction. The electrochemical characterization of the Pd-TiO2/C catalyst for the ORR was carried out by cyclic voltammetry (CV) in the voltage window of 0.04 V to 1.2 V with scan rate of 25 mV/s. With the increase in the crystallite size of TiO2, the peak potential for OH(ads) desorption on the surface of Pd particle shifted to higher potential. This implies that TiO2 might affect the adsorption and desorption of oxygen molecules on Pd catalyst. The performance of Pd-TiO2/C as a cathode material was found to be similar to or better performance than that of Pt/C.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1166/jnn.2011.4385 | DOI Listing |
Angew Chem Int Ed Engl
September 2025
Hefei National Research Center for Physical Sciences at the Microscale, School of Chemistry and Materials Science, State Key Laboratory of Precision and Intelligent Chemistry, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, 230026, China.
The construction of C─N bonds from simple precursors under ambient conditions is a fundamental challenge in green chemistry, especially when it comes to avoiding energy-intensive protocols. Here, we present a continuous flow photocatalytic platform that enables the efficient coupling of C─N bonds between methanol and ammonia at ambient temperature and pressure. By synergistically engineering a Pd clusters-decorated TiO photocatalyst (1Pd/TiO) and a mass transfer-enhanced gas-liquid-solid Taylor flow reactor, the system achieves a remarkable formamide productivity of 256.
View Article and Find Full Text PDFPLoS Med
September 2025
University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America.
Background: Oral emtricitabine/tenofovir disoproxil fumarate (F/TDF) preexposure prophylaxis (PrEP) effectiveness against HIV acquisition highly depends on adherence. For men who have sex with men, a dosing study in the United States (US) population defined clinically meaningful tenofovir diphosphate (TFV-DP) thresholds in dried blood spots (DBS) based on the rounded 25th percentile for 2, 4, and 7 doses/week as 350, 700, and 1,250 fmol/punch. However, divergent efficacy results in the first generation randomized clinical trials of F/TDF PrEP among African women led to several hypotheses to question whether the pharmacology and adherence requirement for oral F/TDF PrEP may be different in cisgender women compared to what is already established for men.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Incorporating atomically thin two-dimensional (2D) materials with optical fibers expands their potential for optoelectronic applications. Recent advancements in chemical vapor deposition have enabled the batch production of these hybrid fibers, paving the way for practical implementation. However, their functionality remains constrained by the integration of a single 2D material, restricting their versatile performance.
View Article and Find Full Text PDFAnal Chem
September 2025
College of Chemistry and Chemical Engineering, Central South University, Hunan, Changsha 410083, China.
While deep learning-enhanced Raman spectroscopy enables rapid sample analysis, model portability among spectrometers remains hindered by systematic interdevice variations. In this study, a Low-Rank Adaptation-based Calibration Transfer method (LoRA-CT) is proposed to perform parameter-efficient fine-tuning of deep learning models across spectrometers. By decomposing weight updates into low-rank matrices, LoRA-CT achieves superior calibration transfer with minimal samples, reducing trainable parameters by 600× compared to full parameter fine-tuning.
View Article and Find Full Text PDFNano Lett
September 2025
KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea.
Sorafenib, a clinically approved multityrosine kinase inhibitor, exhibits poor aqueous solubility, which limits its bioavailability and therapeutic efficacy. In this study, we introduce a solvent-directed self-assembly strategy to modulate the nanostructure of sorafenib without the use of external carriers or complex formulation techniques. In pure water, sorafenib forms large lamellar aggregates, whereas in 30% methanol-water mixtures, it self-assembles into uniform spherical particles approximately 450 nm in diameter.
View Article and Find Full Text PDF