02229nas a2200181   4500008004100000022001400041245011500055210006900170260000800239300001400247490000600261520154900267100002801816700002901844700001901873700003001892856012501922       2019                        eng d  a2050-748800aDirect solar-to-hydrogen generation by quasi-artificial leaf approach: possibly scalable and economical device0 aDirect solartohydrogen generation by quasiartificial leaf approa  cFEB  a3179-31890 v73 a<p>Often, a disadvantage in one area of science may become an advantage in another area. In contrast, a successful concept in one area could work for a complementary area of research too. These two philosophies have been successfully used for solar hydrogen generation and they underscore the necessity to connect relevant concepts. We, herein, report a quasi-artificial leaf (QuAL) device in a wireless configuration with a TiO2/Mn-CdS composite and NiCu as a co-catalyst for possibly scalable as well as commercially viable solar hydrogen production under one sun conditions. The device works at no applied potential and generates 10.5 mL h(-1) (16 mL h(-1)) H-2 with Ni5Cu2.5 alloy (Pt) as a co-catalyst, which corresponds to a power conversion efficiency (PCE) of 4.8% (7.3%). The significant resemblance of NiCu alloy to Pt in terms of its electrochemical activity and electronic structure makes the device more economical. While the millisecond lifetime of electrons in Mn-CdS is known to help for white light emission, the same factor helps to greatly improve charge utilization for H-2 production in the QuAL device. In contrast, the reabsorption of emitted light is a vexing problem in emission applications; however in the present work, reabsorption is successfully utilized to enhance hydrogen yield. Spectroscopy techniques combined with electrocatalytic studies were employed and the results correlated with solar hydrogen generation, demonstrating this as a new pathway to design better solar-light-harvesting architectures.</p>
1 aPatra, Kshirodra, Kumar1 aBharad, Pradnya, Arunrao1 aJain, Vanshika1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/direct-solar-hydrogen-generation-quasi-artificial-leaf-approach-possibly-scalable-and02627nas a2200277   4500008004100000022001400041245011400055210006900169260000800238300001400246490000700260520169300267653003001960653002401990653002002014653002002034653001902054653001702073100003202090700001902122700001702141700001702158700002802175700002302203856012302226       2024                        eng d  a2155-543500aPhotocatalytic regeneration of reactive cofactors with inP quantum dots for the continuous chemical synthesis0 aPhotocatalytic regeneration of reactive cofactors with inP quant  cAPR  a6740-67480 v143 a<p>
	The shuttling of redox-active nicotinamide cofactors between the light and dark cycles is the key to the continuous production of biomass in photosynthesis. The replication of such processes in artificial photosynthetic systems demands fast photoregeneration as well as simultaneous integration of these nicotinamide cofactors into the dark cycle. Here, we report the design of an artificial photosynthetic system for the continuous production of butanol via the constant photoregeneration and consumption of nicotinamide cofactors, powered by an indium phosphide quantum dot (InP QD) photocatalyst and alcohol dehydrogenase (ADH) enzyme, respectively. A strong electrostatic attraction between the oppositely charged InP QDs and electron mediators significantly enhanced the charge extraction and utilization processes, enabling a fast (similar to 30 min, with a turn over frequency of similar to 1333 h(-1)), quantitative (&gt;99%), and selective photoregeneration of enzymatically active nicotinamide cofactors in the light cycle. These photoregenerated nicotinamide cofactors were further coupled in the dark cycle to trigger the ADH oxidoreductase enzyme for the production of butanol, via sequential as well as simultaneous light-dark cycles. The amount of butanol produced under simultaneous light-dark cycles was higher than the stoichiometric limit, proving the constant regeneration and consumption of nicotinamide cofactors in light and dark cycles, respectively. Thus, a proper design and integration of the InP QD-based photocatalytic cycle with the enzymatic cycle led to the effective electron shuttling between light and dark cycles, as seen in photosynthesis.</p>
10aartificial photosynthesis10abiologicalcofactors10acharge transfer10aindiumphosphide10aPhotocatalysis10aquantum dots1 aChakraborty, Indra, Narayan1 aJain, Vanshika1 aRoy, Pradyut1 aKumar, Pawan1 aVinod, Chathakudath, P.1 aPillai, Pramod, P.  uhttps://library.ncl.res.in/content/photocatalytic-regeneration-reactive-cofactors-inp-quantum-dots-continuous-chemical