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1. Photocatalytic Degradation of Fluoroquinolone Antibiotics in Solution by Au@ZnO-rGO-gC3N4 Composites

   https://doi.org/10.3390/catal12020166  

   Machín, Abniel; Fontánez, Kenneth; Duconge, José; Cotto, María C.; Petrescu, Florian I.; Morant, Carmen; Márquez, Francisco (February 2022, Catalysts)

   The photocatalytic degradation of two quinolone-type antibiotics (ciprofloxacin and levofloxacin) in aqueous solution was studied, using catalysts based on ZnO nanoparticles, which were synthesized by a thermal procedure. The efficiency of ZnO was subsequently optimized by incorporating different co-catalysts of gC3N4, reduced graphene oxide, and nanoparticles of gold. The catalysts were fully characterized by electron microscopy (TEM and SEM), XPS, XRD, Raman, and BET surface area. The most efficient catalyst was 10%Au@ZnONPs-3%rGO-3%gC3N4, obtaining degradations of both pollutants above 96%. This catalyst has the largest specific area, and its activity was related to a synergistic effect, involving factors such as the surface of the material and the ability to absorb radiation in the visible region, mainly produced by the incorporation of rGO and gC3N4 in the semiconductor. The use of different scavengers during the catalytic process, was used to establish the possible photodegradation mechanism of both antibiotics. 

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2. Metal–Organic Frameworks and Their Derivatives for Photocatalytic Water Splitting

   https://doi.org/10.3390/inorganics5030040  

   Song, Fuzhan; Li, Wei; Sun, Yujie (September 2017, Inorganics)

   Amongst many strategies for renewable energy conversion, light-driven water splitting to produce clean H2 represents a promising approach and has attracted increasing attention in recent years. Owing to the multi-electron/multi-proton transfer nature of water splitting, low-cost and competent catalysts are needed. Along the rapid development of metal–organic frameworks (MOFs) during the last two decades or so, MOFs have been recognized as an interesting group of catalysts or catalyst supports for photocatalytic water splitting. The modular synthesis, intrinsically high surface area, tunable porosity, and diverse metal nodes and organic struts of MOFs render them excellent catalyst candidates for photocatalytic water splitting. To date, the application of MOFs and their derivatives as photocatalysts for water splitting has become a burgeoning field. Herein, we showcase several representative MOF-based photocatalytic systems for both H2 and O2 evolution reactions (HER, OER). The design principle of each catalytic system is specifically discussed. The current challenges and opportunities of utilizing MOFs for photocatalytic water splitting are discussed in the end. 

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3. Characterization of Platinum Nanoparticles Utilized in Photocatalytic Hydrogen Synthesis*

   Boyce, Daniel; Colton, John; Richards, Matthew (March 2019, Bulletin of the American Physical Society)

   Hydrogen (H2) gas is a possible alternate fuel to help meet increasing worldwide energy needs, but a major obstacle in the use of H2 for green, environmentally-friendly fuel is the energetic and chemical requirements to synthesize the gas. We are studying the use of photocatalytic reactions to produce H2, where a light-absorbing substance acts as a catalyst in shuttling electrons from a donor to protons that are reduced into H2. Previous research conducted at BYU showed that platinum nanoparticles bound to ferritin catalyzed the photoreaction of methyl viologen to reduce protons in an organic acid offered an increase in hydrogen production efficiency by up to 100 times over platinum black (a commonly available platinum-based catalyst). We are reporting on our efforts to optimize the synthesis of the platinum nanoparticles bound to ferritin that are used in this photocatalytic system and how we characterize these nanoparticles, as well as how these characteristics affect H2 production. *We'd like to thank the Brigham Young University Physics Department and the National Science Foundation (grant no. 1757998) for their generous funding. 

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4. A chemoinformatics approach for the characterization of hybrid nanomaterials: safer and efficient design perspective

   https://doi.org/10.1039/c9nr01162e  

   Mikolajczyk, Alicja; Sizochenko, Natalia; Mulkiewicz, Ewa; Malankowska, Anna; Rasulev, Bakhtiyor; Puzyn, Tomasz (June 2019, Nanoscale)

   In this study, photocatalytic properties and in vitro cytotoxicity of 29 TiO 2 -based multi-component nanomaterials ( i.e. , hybrids of more than two composition types of nanoparticles) were evaluated using a combination of the experimental testing and supervised machine learning modeling. TiO 2 -based multi-component nanomaterials with metal clusters of silver, and their mixtures with gold, palladium, and platinum were successfully synthesized. Two activities, photocatalytic activity and cytotoxicity, were studied. A novel cheminformatic approach was developed and applied for the computational representation of the photocatalytic activity and cytotoxicity effect. In this approach, features of investigated TiO 2 -based hybrid nanomaterials were reflected by a series of novel additive descriptors for hybrid and hybrid nanostructures (denoted as “hybrid nanosctructure descriptors”). These descriptors are based on quantum chemical calculations and the Smoluchowski equation. The obtained experimental data and calculated hybrid-nanostructure descriptors were used to develop novel predictive Quantitative Structure–Activity Relationship computational models (called “nano-QSAR mix ”). The proposed modeling approach is an initial step in the understanding of the relationships between physicochemical properties of hybrid nanoparticles, their toxicity, and photochemical activity under UV-vis irradiation. Acquired knowledge supports the safe-by-design approaches relevant to the development of efficient hybrid nanomaterials with reduced hazardous effects. 

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5. Characterization of Platinum Nanoparticles Utilized in Photocatalytic Hydrogen Synthesis*

   Boyce, Daniel; Colton, John; Richards, Matt (March 2018, Bulletin of the American Physical Society)

   As energy needs grow ever greater in today's world, many scientists are investigating possible replacements for fossil fuels as an energy source. The use of hydrogen (H2) gas in particular is undergoing a significant amount of research, but a major obstacle in the use of H2 for green, environmentally-friendly fuel is the energetic and chemical requirement to synthesize the gas. A possibility in satisfying current and future H2 production needs is the use of photocatalytic reactions, where a light-absorbing substance acts as a catalyst in shuttling electrons from a donor to protons that are reduced into H2. Previous research conducted at BYU found such a system where platinum nanoparticles bound to ferritin catalyzed the photoreaction of methyl viologen to reduce protons in an organic acid, which offered a one hundred-fold increase in H2 production efficiency over photocatalytic reactions catalyzed by bulk platinum. We are reporting on our efforts to optimize the synthesis of the platinum nanoparticles bound to ferritin that are used in this photocatalytic system and how we characterize these nanoparticles. *We'd like to thank the Brigham Young University Physics Department and the National Science Foundation (grant no. 1757998) for their generous funding. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2018.4CS.J03.3 

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