02813nas a2200301   4500008004100000245016300041210006900204260000800273300001200281490000600293520178700299653002402086653002102110653002102131653002102152653002402173100002302197700001802220700001902238700001702257700001702274700001602291700001902307700001702326700001802343700002102361856012902382       2026                        eng d00aPhotoluminescence decay lifetime study of hydrothermally synthesized highly porous ruthenium-silica composite for optical dissolved oxygen sensing application0 aPhotoluminescence decay lifetime study of hydrothermally synthes  cJAN  a937-9490 v93 a<p>
	Pore size and surface area of photoluminescence (PL)-based transition metal composites play crucial roles in facilitating oxygen diffusion, thereby enhancing the response and sensitivity of optical dissolved oxygen (DO) sensors. In this study, we successfully applied the hydrothermal method to synthesize a porous ruthenium composite embedded in a silica matrix, demonstrating its effectiveness for optical DO sensing applications. The ruthenium-silica (Ru-Si) composites were synthesized using Ru(bpy)3 2+ and tetraethyl orthosilicate (TEOS) as precursors, with reaction temperatures ranging from 120 degrees C to 200 degrees C over a fixed duration of 4 h. The structural, morphological, and compositional characterization techniques confirmed the successful synthesis and evaluated the porosity, surface features, and chemical structure of the resulting composites. The optimized Ru-Si composite exhibited the highest porosity, characterized by a specific surface area of 996.78 m2 g- 1, and exhibited the highest decay lifetime of 8.14 mu s in deionized (DI) water, compared to other composites. Importantly, we demonstrate an excellent linear response of the synthesized Ru-Si composite to DO concentrations ranging from 2.58 to 11.16 mg L-1, with a Stern-Volmer constant of 0.12. Furthermore, a density functional theory study was conducted to investigate the electronic transitions and to elucidate the oxygen quenching mechanism of the excited Ru composite with molecular oxygen. The calculated photophysical parameters of the composite show good agreement with the experimental results. Preliminary results suggest that the synthesized Ru-Si with high pore size and surface area could be an efficient and effective composite for use in DO sensing applications.</p>
10aHydrothermal method10aopticalDO sensor10aoxygen quenching10aphotoluminescent10aruthenium composite1 aHattale, Gangadhar1 aKadam, Rutuja1 aVirole, Vishal1 aPandya, Rinu1 aPaul, Aditya1 aKumar, Ajay1 aShevate, Rahul1 aVanka, Kumar1 aSaha, Avishek1 aKanawade, Rajesh  uhttps://library.ncl.res.in/content/photoluminescence-decay-lifetime-study-hydrothermally-synthesized-highly-porous-ruthenium02390nas a2200325   4500008004100000022001400041245009900055210006900154260000800223300001100231490000700242520135600249653001901605653002101624653002401645653002401669653003101693100001801724700002301742700001901765700001901784700002001803700001701823700001601840700001901856700002001875700002101895700001801916856013001934       2026                        eng d  a1861-472800aPolysulfone-based polymer carbon dot membrane for optical dissolved oxygen sensing application0 aPolysulfonebased polymer carbon dot membrane for optical dissolv  cMAR  ae706850 v213 a<p>
	The precise monitoring of dissolved oxygen (DO) is essential across industrial, environmental, and biomedical applications. However, the state-of-the-art DO sensing methods often suffer from inherent limitations, which hinder their effectiveness for real-time and long-term DO monitoring. Optical DO sensing, despite its advantages, utilizes expensive metal complexes and is prone to photobleaching and slow response time. Here, we introduce a novel polymer carbon dot (PCD) as a promising candidate for lifetime-based optical DO sensing. The PCD is a metal-free, nontoxic, fluorescent, long decay-lifetime material that is synthesized through hydrothermal method. Our fluorescent PCD exhibits high emission quantum yield (24.32%), long decay-lifetime (10.43 &amp; micro;s), and a linear response to DO concentrations ranging from 0.7 to 12.7 mg/L, with a Stern-Volmer constant of 0.1115. Further, to obtain better oxygen diffusion, high porosity, optical transparency, and high flexibility, PCD was embedded into a polysulfone matrix (PSF_PCD). The PSF_PCD membrane shows better results for the decay lifetime (9.4 &amp; micro;s), surface energy (40.26 mN/m), and average pore diameter of 5 nm. Hence, the obtained results demonstrate the applicability of the PCD in optical DO sensors for real-time and long-term monitoring of DO levels.</p>
10adecay lifetime10adissolved oxygen10aHydrothermal method10apolymer carbon dots10apolysulfone-based membrane1 aKadam, Rutuja1 aHattale, Gangadhar1 aVirole, Vishal1 aPal, Sanjivani1 aAbraham, Athira1 aPaul, Aditya1 aKumar, Ajay1 aShevate, Rahul1 aBanpurkar, Arun1 aKanawade, Rajesh1 aSaha, Avishek  uhttps://library.ncl.res.in/content/polysulfone-based-polymer-carbon-dot-membrane-optical-dissolved-oxygen-sensing-application