02455nas a2200241 4500008004100000022001400041245012100055210006900176260000800245300001400253490000700267520164400274100001901918700001801937700001701955700001601972700001701988700001902005700001702024700002002041700002102061856013102082 2025 eng d a2040-336400aInvestigating the visible range photoresponse of an organic single-crystal analogue of the green fluorescent protein0 aInvestigating the visible range photoresponse of an organic sing cAPR a8614-86230 v173 a

The growing demand for lightweight, flexible, semi-transparent and low-cost photodetectors (PDs) in wearable electronics and optical communication systems has prompted studies to investigate organic materials as feasible alternatives to conventional inorganic PDs. However, modern organic PDs often face responsivity, detectivity, and photoresponse speed limitations, particularly in the visible range. Here, we present the photoresponse of an organic single-crystal analogue of the green fluorescent protein (GFP) chromophore photodetector, fabricated on a silicon nitride substrate. A significant increase in photocurrent was detected upon illumination with visible wavelengths (532 nm, 630 nm, and halogen light). A remarkably consistent and repeatable photoresponse was obtained during the ON and OFF illumination cycles. The device showed the dependence of photocurrent on the applied bias voltages. The measured photocurrent, responsivity, detectivity, rise time, decay time, noise equivalent power and external quantum efficiency are studied for different wavelengths. Strikingly, the fabricated device demonstrates excellent performance in the visible region compared to several conventional organic and inorganic PDs. The observed responsivity and detectivity values for the device are 98 mA W-1 and 7.94 x 108 Jones, respectively. Furthermore, the device also exhibits rapid photoresponse dynamics with a rise time of 180 ms and a decay time of 152 ms. The excellent photodetection features indicate that the single crystal GFP could serve as a versatile broadband material for future applications in optoelectronics.

1 aVirole, Vishal1 aDabke, Niteen1 aVerma, Sahil1 aKumar, Ajay1 aPandya, Rinu1 aHusale, Sudhir1 aVanka, Kumar1 aGonnade, Rajesh1 aKanawade, Rajesh uhttps://library.ncl.res.in/content/investigating-visible-range-photoresponse-organic-single-crystal-analogue-green-fluorescent02271nas a2200361 4500008004100000022001400041245016600055210006900221260000800290300001100298490000800309520108600317653000801403653002601411653002001437653002701457653003201484653002301516100001801539700001601557700001601573700001901589700002201608700002301630700001801653700001901671700001601690700001901706700001601725700001901741700002101760856012801781 2025 eng d a0360-319900aOptimisation of metallic bismuth nanoparticle supported Pt-Bi(x%)/C hybrid electrocatalyst for cost effective and efficient hydrogen production in alkaline media0 aOptimisation of metallic bismuth nanoparticle supported PtBixC h cAUG a1506990 v1613 a

The present study employed a simple mechanochemical method followed by 24-h ultrasonication to synthesize oxide-free metallic bismuth (Bi) nanoparticles. This was further used to synthesize a Pt-Bi(x%)/C (NC-x) hybrid electrocatalyst for the hydrogen evolution reaction in alkaline media. X-ray photoelectron spectroscopy and contact angle measurements reveal, Bi modifies the electronic structure and surface morphology of the Pt/C electrocatalyst, thus enhancing reaction kinetics and active site availability. The relative three-electrode study reveals that optimised NC-20 electrocatalyst reduces the overpotentials by 10.44 % and enhances the current density by 53 % compared to commercial Pt/C. The practical applicability of the NC-20 electrocatalyst was studied with the 13 cm2 single cell anion exchange membrane electrolyser. The catalyst demonstrates promising performance where the current density of NC-20//IrO2 relatively increases by 22.6 % compared to standard Pt/ C//IrO2, and shows continuous production and stable performance when monitored for 30 h.

10aAEM10aBismuth nanoparticles10aelectrocatalyst10aFull cell electrolysis10ahydrogen evolution reaction10awater electrolysis1 aDokhe, Revati1 aUgale, Atul1 aDube, Onkar1 aVarpe, Vaibhav1 aGalave, Chaitanya1 aHattale, Gangadhar1 aKadam, Rutuja1 aVirole, Vishal1 aKumar, Ajay1 aHusale, Sudhir1 aNatu, Varun1 aShevate, Rahul1 aKanawade, Rajesh uhttps://library.ncl.res.in/content/optimisation-metallic-bismuth-nanoparticle-supported-pt-bixc-hybrid-electrocatalyst-cost02813nas 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

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.

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

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 & 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 & 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.

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