All-carbon microporous graphitic photocatalyst-promoted reduction of CO2 to CO in the absence of metals or dopant elements

[EN] Microporous graphitic carbon (mp-C) derived from the pyrolysis of alpha-, beta-, and gamma-cyclodextrins exhibited photocatalytic activity in CO2-saturated acetonitrile-water upon irradiation with UV-Vis light and in the presence of triethanolamine, forming H-2 (19 mu mol h(-1)) and CO (23 mu mol h(-1)) accompanied by a lesser proportion of CH4 (4 mu mol h(-1)). The most efficient was the mp-C material derived from alpha-cyclodextrin (mp-C-alpha) and having a pore dimension of 0.68 nm. The process also occured, although to a much lesser extent, under simulated sunlight or with UV-Vis irradiation in the absence of a sacrificial agent, with H2O being the electron donor. The origin of the CO was proved by isotopic C-13 labelling experiments. Photocurrent measurements proved the occurrence of charge separation and the increase in photocurrent intensity in the presence of CO2. Transient absorption spectroscopy was used to detect the charge separate state decay in the microsecond time scale and proved that a fraction of the photogenerated electrons were able to react with CO2.Financial support by the Spanish Ministry of Science and Innovation (Severo Ochoa, PID-2021-12607OB-C21 and RTI2018-89237-CO2-1) and Generalitat Valenciana (Prometeo 2021/083) are gratefully acknowledged. A. G.-M. thanks the Spanish Ministry of Science and Innovation for a postgraduate scholarship.Garcia-Mulero, A.; Asiri, AM.; Albero-Sancho, J.; Primo Arnau, AM.; García Gómez, H. (2022). All-carbon microporous graphitic photocatalyst-promoted reduction of CO2 to CO in the absence of metals or dopant elements. Nanoscale. 14(32):11575-11582. https://doi.org/10.1039/d2nr02655d1157511582143

Plasma-Induced Defects Enhance the Visible-Light Photocatalytic Activity of MIL-125(Ti)-NH2 for Overall Water Splitting

This is the peer reviewed version of the following article: M. Cabrero-Antonino, J. Albero, C. García-Vallés, M. Álvaro, S. Navalón, H. García, Chem. Eur. J. 2020, 26, 15682, which has been published in final form at https://doi.org/10.1002/chem.202003763. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] Defect engineering in metal-organic frameworks is commonly performed by using thermal or chemical treatments. Herein we report that oxygen plasma treatment generates structural defects on MIL-125(Ti)-NH2, leading to an increase in its photocatalytic activity. Characterization data indicate that plasma-treated materials retain most of their initial crystallinity, while exhibiting somewhat lower surface area and pore volume. XPS and FT-IR spectroscopy reveal that oxygen plasma induces MIL-125(Ti)-NH2 partial terephthalate decarboxylation and an increase in the Ti-OH population. Thermogravimetric analyses confirm the generation of structural defects by oxygen plasma and allowed an estimation of the resulting experimental formula of the treated MIL-125(Ti)-NH2 solids. SEM analyses show that oxygen plasma treatment of MIL-125(Ti)-NH2 gradually decreases its particle size. Importantly, diffuse reflectance UV/Vis spectroscopy and valence band measurements demonstrate that oxygen plasma treatment alters the MIL-125(Ti)-NH2 band gap and, more significantly, the alignment of highest occupied and lowest unoccupied crystal orbitals. An optimal oxygen plasma treatment to achieve the highest efficiency in water splitting with or without methanol as sacrificial electron donor under UV/Vis or simulated sunlight was determined. The optimized plasma-treated MIL-125(Ti)-NH2 photocatalyst acts as a truly heterogeneous photocatalyst and retains most of its initial photoactivity and crystallinity upon reuse.S.N. thanks the Fundacion Ramon Areces (XVIII Concurso Nacional para la Adjudicacion de Ayudas a la Investigacion en Ciencias de la Vida y de la Materia, 2016), the Ministerio de Ciencia, Innovacion y Universidades RTI 2018-099482-A-I00 project, the Generalitat Valenciana grupos de investigacion consolidables 2019 (ref: AICO/2019/214) project, and the AVI project (INNEST/2020/111) for financial support. Financial support by the European Union (LoterCO2M), Spanish Ministry of Science, Innovation and Universities (Severo Ochoa and RTI2018-098237-B-C21), and Generalitat Valenciana (Prometeo 2017-083) is also gratefully acknowledged.Cabrero-Antonino, M.; Albero-Sancho, J.; García-Vallés, C.; Alvaro Rodríguez, MM.; Navalón Oltra, S.; García Gómez, H. (2020). Plasma-Induced Defects Enhance the Visible-Light Photocatalytic Activity of MIL-125(Ti)-NH2 for Overall Water Splitting. Chemistry - A European Journal. 26(67):15682-15689. https://doi.org/10.1002/chem.202003763S15682156892667Dhakshinamoorthy, A., Asiri, A. M., & García, H. (2016). Metal–Organic Framework (MOF) Compounds: Photocatalysts for Redox Reactions and Solar Fuel Production. Angewandte Chemie International Edition, 55(18), 5414-5445. doi:10.1002/anie.201505581Dhakshinamoorthy, A., Asiri, A. M., & Garcia, H. (2016). Metall‐organische Gerüstverbindungen: Photokatalysatoren für Redoxreaktion und die Produktion von Solarbrennstoffen. Angewandte Chemie, 128(18), 5504-5535. doi:10.1002/ange.201505581Dhakshinamoorthy, A., Li, Z., & Garcia, H. (2018). Catalysis and photocatalysis by metal organic frameworks. Chemical Society Reviews, 47(22), 8134-8172. doi:10.1039/c8cs00256hZhang, T., & Lin, W. (2014). Metal–organic frameworks for artificial photosynthesis and photocatalysis. Chem. Soc. Rev., 43(16), 5982-5993. doi:10.1039/c4cs00103fWang, J.-L., Wang, C., & Lin, W. (2012). Metal–Organic Frameworks for Light Harvesting and Photocatalysis. ACS Catalysis, 2(12), 2630-2640. doi:10.1021/cs3005874Wen, M., Mori, K., Kuwahara, Y., An, T., & Yamashita, H. (2018). Design of Single-Site Photocatalysts by Using Metal-Organic Frameworks as a Matrix. Chemistry - An Asian Journal, 13(14), 1767-1779. doi:10.1002/asia.201800444Ding, M., Flaig, R. W., Jiang, H.-L., & Yaghi, O. M. (2019). Carbon capture and conversion using metal–organic frameworks and MOF-based materials. Chemical Society Reviews, 48(10), 2783-2828. doi:10.1039/c8cs00829aLi, D., Kassymova, M., Cai, X., Zang, S.-Q., & Jiang, H.-L. (2020). Photocatalytic CO2 reduction over metal-organic framework-based materials. Coordination Chemistry Reviews, 412, 213262. doi:10.1016/j.ccr.2020.213262Zhang, T., Jin, Y., Shi, Y., Li, M., Li, J., & Duan, C. (2019). Modulating photoelectronic performance of metal–organic frameworks for premium photocatalysis. Coordination Chemistry Reviews, 380, 201-229. doi:10.1016/j.ccr.2018.10.001Luo, H., Zeng, Z., Zeng, G., Zhang, C., Xiao, R., Huang, D., … Tian, S. (2020). Recent progress on metal-organic frameworks based- and derived-photocatalysts for water splitting. Chemical Engineering Journal, 383, 123196. doi:10.1016/j.cej.2019.123196Schneider, J., Matsuoka, M., Takeuchi, M., Zhang, J., Horiuchi, Y., Anpo, M., & Bahnemann, D. W. (2014). Understanding TiO2 Photocatalysis: Mechanisms and Materials. Chemical Reviews, 114(19), 9919-9986. doi:10.1021/cr5001892Fujishima, A., Rao, T. N., & Tryk, D. A. (2000). Titanium dioxide photocatalysis. Journal of Photochemistry and Photobiology C: Photochemistry Reviews, 1(1), 1-21. doi:10.1016/s1389-5567(00)00002-2FUJISHIMA, A., ZHANG, X., & TRYK, D. (2008). TiO2 photocatalysis and related surface phenomena. Surface Science Reports, 63(12), 515-582. doi:10.1016/j.surfrep.2008.10.001Zhu, J., Li, P.-Z., Guo, W., Zhao, Y., & Zou, R. (2018). Titanium-based metal–organic frameworks for photocatalytic applications. Coordination Chemistry Reviews, 359, 80-101. doi:10.1016/j.ccr.2017.12.013Chen, X., Peng, X., Jiang, L., Yuan, X., Yu, H., Wang, H., … Xia, Q. (2020). Recent advances in titanium metal–organic frameworks and their derived materials: Features, fabrication, and photocatalytic applications. Chemical Engineering Journal, 395, 125080. doi:10.1016/j.cej.2020.125080Remiro-Buenamañana, S., Cabrero-Antonino, M., Martínez-Guanter, M., Álvaro, M., Navalón, S., & García, H. (2019). Influence of co-catalysts on the photocatalytic activity of MIL-125(Ti)-NH2 in the overall water splitting. Applied Catalysis B: Environmental, 254, 677-684. doi:10.1016/j.apcatb.2019.05.027An, Y., Xu, B., Liu, Y., Wang, Z., Wang, P., Dai, Y., … Huang, B. (2017). Photocatalytic Overall Water Splitting over MIL-125(Ti) upon CoPi and Pt Co-catalyst Deposition. ChemistryOpen, 6(6), 701-705. doi:10.1002/open.201700100Hendon, C. H., Tiana, D., Fontecave, M., Sanchez, C., D’arras, L., Sassoye, C., … Walsh, A. (2013). Engineering the Optical Response of the Titanium-MIL-125 Metal–Organic Framework through Ligand Functionalization. Journal of the American Chemical Society, 135(30), 10942-10945. doi:10.1021/ja405350uHisatomi, T., & Domen, K. (2019). Reaction systems for solar hydrogen production via water splitting with particulate semiconductor photocatalysts. Nature Catalysis, 2(5), 387-399. doi:10.1038/s41929-019-0242-6Nasalevich, M. A., Hendon, C. H., Santaclara, J. G., Svane, K., van der Linden, B., Veber, S. L., … Gascon, J. (2016). Electronic origins of photocatalytic activity in d0 metal organic frameworks. Scientific Reports, 6(1). doi:10.1038/srep23676Ma, X., Wang, L., Zhang, Q., & Jiang, H. (2019). Switching on the Photocatalysis of Metal–Organic Frameworks by Engineering Structural Defects. Angewandte Chemie International Edition, 58(35), 12175-12179. doi:10.1002/anie.201907074Ma, X., Wang, L., Zhang, Q., & Jiang, H. (2019). Switching on the Photocatalysis of Metal–Organic Frameworks by Engineering Structural Defects. Angewandte Chemie, 131(35), 12303-12307. doi:10.1002/ange.201907074De Vos, A., Hendrickx, K., Van Der Voort, P., Van Speybroeck, V., & Lejaeghere, K. (2017). Missing Linkers: An Alternative Pathway to UiO-66 Electronic Structure Engineering. Chemistry of Materials, 29(7), 3006-3019. doi:10.1021/acs.chemmater.6b05444Taddei, M., Schukraft, G. M., Warwick, M. E. A., Tiana, D., McPherson, M. J., Jones, D. R., & Petit, C. (2019). Band gap modulation in zirconium-based metal–organic frameworks by defect engineering. Journal of Materials Chemistry A, 7(41), 23781-23786. doi:10.1039/c9ta05216jSvane, K. L., Bristow, J. K., Gale, J. D., & Walsh, A. (2018). Vacancy defect configurations in the metal–organic framework UiO-66: energetics and electronic structure. Journal of Materials Chemistry A, 6(18), 8507-8513. doi:10.1039/c7ta11155jHendrickx, K., Vanpoucke, D. E. P., Leus, K., Lejaeghere, K., Van Yperen-De Deyne, A., Van Speybroeck, V., … Hemelsoet, K. (2015). Understanding Intrinsic Light Absorption Properties of UiO-66 Frameworks: A Combined Theoretical and Experimental Study. Inorganic Chemistry, 54(22), 10701-10710. doi:10.1021/acs.inorgchem.5b01593Wang, Z., Zhang, Y., Neyts, E. C., Cao, X., Zhang, X., Jang, B. W.-L., & Liu, C. (2018). Catalyst Preparation with Plasmas: How Does It Work? ACS Catalysis, 8(3), 2093-2110. doi:10.1021/acscatal.7b03723Jiang, Z., Ge, L., Zhuang, L., Li, M., Wang, Z., & Zhu, Z. (2019). Fine-Tuning the Coordinatively Unsaturated Metal Sites of Metal–Organic Frameworks by Plasma Engraving for Enhanced Electrocatalytic Activity. ACS Applied Materials & Interfaces, 11(47), 44300-44307. doi:10.1021/acsami.9b15794Xiang, W., Ren, J., Chen, S., Shen, C., Chen, Y., Zhang, M., & Liu, C. (2020). The metal–organic framework UiO-66 with missing-linker defects: A highly active catalyst for carbon dioxide cycloaddition. Applied Energy, 277, 115560. doi:10.1016/j.apenergy.2020.115560Primo, A., Franconetti, A., Magureanu, M., Mandache, N. B., Bucur, C., Rizescu, C., … Garcia, H. (2018). Engineering active sites on reduced graphene oxide by hydrogen plasma irradiation: mimicking bifunctional metal/supported catalysts in hydrogenation reactions. Green Chemistry, 20(11), 2611-2623. doi:10.1039/c7gc03397dGuo, Y., Gao, X., Zhang, C., Wu, Y., Chang, X., Wang, T., … Li, X. (2019). Plasma modification of a Ni based metal–organic framework for efficient hydrogen evolution. Journal of Materials Chemistry A, 7(14), 8129-8135. doi:10.1039/c9ta00696fDan-Hardi, M., Serre, C., Frot, T., Rozes, L., Maurin, G., Sanchez, C., & Férey, G. (2009). A New Photoactive Crystalline Highly Porous Titanium(IV) Dicarboxylate. Journal of the American Chemical Society, 131(31), 10857-10859. doi:10.1021/ja903726mPeng, Y., Rendón-Patiño, A., Franconetti, A., Albero, J., Primo, A., & García, H. (2020). Photocatalytic Overall Water Splitting Activity of Templateless Structured Graphitic Nanoparticles Obtained from Cyclodextrins. ACS Applied Energy Materials, 3(7), 6623-6632. doi:10.1021/acsaem.0c00789Melillo, A., Cabrero-Antonino, M., Navalón, S., Álvaro, M., Ferrer, B., & García, H. (2020). Enhancing visible-light photocatalytic activity for overall water splitting in UiO-66 by controlling metal node composition. Applied Catalysis B: Environmental, 278, 119345. doi:10.1016/j.apcatb.2020.119345Ebbesen, T. W., & Ferraudi, G. (1983). Photochemistry of methyl viologen in aqueous and methanolic solutions. The Journal of Physical Chemistry, 87(19), 3717-3721. doi:10.1021/j100242a028García, H., & Navalón, S. (Eds.). (2018). 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Long-Term Photostability in Terephthalate Metal-Organic Frameworks

This is the peer reviewed version of the following article: Mateo, Diego, et al. Long-Term Photostability in Terephthalate Metal-Organic Frameworks. Angewandte Chemie (International Ed.), vol. 58, no. 49, Wiley, 2019, pp. 17843 48, doi:10.1002/anie.201911600, which has been published in final form at https://doi.org/10. 1002/anie.201911600. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] Prolonged (weeks) UV/Vis irradiation under Ar of UiO-66(Zr), UiO66 Zr-NO2, MIL101 Fe, MIL125 Ti-NH2, MIL101 Cr and MIL101 Cr(Pt) shows that these MOFs undergo photodecarboxylation of benzenedicarboxylate (BDC) linker in a significant percentage depending on the structure and composition of the material. Routine characterization techniques such as XRD, UV/Vis spectroscopy and TGA fail to detect changes in the material, although porosity and surface area change upon irradiation of powders. In contrast to BCD-containing MOFs, zeolitic imidazolate ZIF-8 does not evolve CO2 or any other gas upon irradiation.Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa, and CTQ2015-69563-CO2-R1) and by the Generalitat Valenciana (Prometeo 2013-014) is gratefully acknowledged. J.A. thanks the Universitat Politecnica de Valencia for a postdoctoral scholarship. D.M. also thanks Spanish Ministry of Science for PhD Scholarship.Mateo-Mateo, D.; Santiago-Portillo, A.; Albero-Sancho, J.; Navalón Oltra, S.; Alvaro Rodríguez, MM.; García Gómez, H. (2019). Long-Term Photostability in Terephthalate Metal-Organic Frameworks. Angewandte Chemie International Edition. 58(49):17843-17848. https://doi.org/10.1002/anie.201911600S1784317848584

Glutathione-Triggered catalytic response of Copper-Iron mixed oxide Nanoparticles. Leveraging tumor microenvironment conditions for chemodynamic therapy

Heterogeneous catalysis has emerged as a promising alternative for the development of new cancer therapies. In addition, regarding the tumor microenvironment as a reactor with very specific chemical features has provided a new perspective in the search for catalytic nanoarchitectures with specific action against chemical species playing a key role in tumor metabolism. One of these species is glutathione (GSH), whose depletion is the cornerstone of emerging strategies in oncology, since this metabolite plays a pivotal regulatory role as antioxidant agent, dampening the harmful effects of intracellular reactive oxidative species (ROS). Herein, we present copper-iron oxide spinel nanoparticles that exhibit a versatile and selective catalytic response to reduce GSH levels while generating ROS in a cascade reaction. We demonstrate a clear correlation between GSH depletion and apoptotic cell death in tumor cells in the presence of the copper-iron nanocatalyst. Furthermore, we also provide a novel analytical protocol, alternative to state-of-the-art commercial kits, to accurately monitoring the concentration of GSH intracellular levels in both tumor and healthy cells. We observe a selective action of the nanoparticles, with lower toxicity in healthy cell lines, whose intrinsic GSH levels are lower, and intense apoptosis in tumor cells accompanied by a fast reduction of GSH levels

Gas-Phase Photochemical Overall H2 S Splitting by UV Light Irradiation

[EN] Splitting of hydrogen sulfide is achieved to produce valueadded chemicals. Upon irradiation at 254 nm in the gas phase and in the absence of catalysts or photocatalysts at near room temperature, H2S splits into stoichiometric amounts of H2 and S with a quantum efficiency close to 50%. No influence of the presence of CH4 and CO2 (typical components in natural gas and biogas in which H2S is an unwanted component) on the efficiency of overall H2S splitting was observed. A mechanism for the H2 and S formation is proposed.Financial support by the Spanish Ministry of Economy and R1) and Generalitat Valenciana (Prometeo 2013-014) is gratefully acknowledged. Thanks are due to Dr. J. A. Agullo-Macia for performing a preliminary experiment.Garcia-Baldovi, H.; Albero-Sancho, J.; Ferrer Ribera, RB.; Mateo-Mateo, D.; Alvaro Rodríguez, MM.; García Gómez, H. (2017). Gas-Phase Photochemical Overall H2 S Splitting by UV Light Irradiation. ChemSusChem. 10(9):1996-2000. https://doi.org/10.1002/cssc.201700294S1996200010

Non-destructive production of exosomes loaded with ultrathin Palladium nanosheets for targeted bioorthogonal catalysis

The use of exosomes as selective delivery vehicles of therapeutic agents, such as drugs or hyperthermia-capable nanoparticles, is being intensely investigated on account of their preferential tropism toward their parental cells. However, the methods used to introduce a therapeutic load inside exosomes often involve disruption of their membrane, which may jeopardize their targeting capabilities, attributed to their surface integrins. On the other hand, in recent years bio-orthogonal catalysis has emerged as a new tool with a myriad of potential applications in medicine. These bio-orthogonal processes, often based on Pd-catalyzed chemistry, would benefit from systems capable of delivering the catalyst to target cells. It is therefore highly attractive to combine the targeting capabilities of exosomes and the bio-orthogonal potential of Pd nanoparticles to create new therapeutic vectors. In this protocol, we provide detailed information on an efficient procedure to achieve a high load of catalytically active Pd nanosheets inside exosomes, without disrupting their membranes. The protocol involves a multistage process in which exosomes are first harvested, subjected to impregnation with a Pd salt precursor followed by a mild reduction process using gas-phase CO, which acts as both a reducing and growth-directing agent to produce the desired nanosheets. The technology is scalable, and the protocol can be conducted by any researcher having basic biology and chemistry skills in ~3 d.We gratefully acknowledge financial support from the ERC Advanced Grant CADENCE (grant no. ERC-2016-ADG-742684) and the EPSRC (Healthcare Technology Challenge award no. EP/N021134/1). M.S.-A. thanks the Spanish Government for an FPU PhD research fellowship. B.R.-R. thanks the EC (grant no. H2020-MSCA-IF-2014–658833). V.S. acknowledges the financial support of Ministerio de Ciencia, Innovación y Universidades, Programa Retos Investigación, Proyecto REF: RTI2018-099019-A-I00. M.A. acknowledges the financial support of the ERC Consolidator Grant programme (grant no. ERC-2013-CoG-614715). P.M.-D. also thanks Instituto de Salud Carlos III (PI19/01007). We also thank CIBER-BBN, an initiative funded by the VI National R&D&i Plan 2008–2011 financed by the Instituto de Salud Carlos III and by Fondo Europeo de Desarrollo Regional (Feder) ‘Una manera de hacer Europa’, with the assistance of the European Regional Development Fund. This study is also partially funded by the Aragon Government (T57_17R p) cofounded by Feder 2014–2020 ‘Building Europe from Aragon’.Peer reviewe

Efficient encapsulation of theranostic nanoparticles in cell-derived exosomes: leveraging the exosomal biogenesis pathway to obtain hollow gold nanoparticle-hybrids

Exosomes can be considered natural targeted delivery systems able to carry exogenous payloads, drugs or theranostic nanoparticles (NPs). This work aims to combine the therapeutic capabilities of hollow gold nanoparticles (HGNs) with the unique tumor targeting properties provided by exosomes. Here, we tested different methods to encapsulate HGNs (capable of absorbing light in the NIR region for selective thermal ablation) into murine melanoma cells derived exosomes (B16-F10-exos), including electroporation, passive loading by diffusion, thermal shock, sonication and saponin-assisted loading. These methods gave less than satisfactory results: although internalization of relatively large NPs into B16-F10-exos was achieved by almost all the physicochemical methods tested, only about 15% of the exosomes were loaded with NPs and several of those processes had a negative effect regarding the morphology and integrity of the loaded exosomes. In a different approach, B16-F10 cells were pre-incubated with PEGylated HGNs (PEG-HGNs) in an attempt to incorporate the NPs into the exosomal biogenesis pathway. The results were highly successful: exosomes recovered from the supernatant of the cell culture showed up to 50% of HGNs internalization. The obtained hybrid HGN-exosome vectors were characterized with a battery of techniques to make sure that internalization of HGNs did not affect exosome characteristics compared with other strategies. PEG-HGNs were released through the endosomal-exosome biogenesis pathway confirming that the isolated vesicles were exosomes

High-current water electrolysis performance of metal phosphides grafted on porous 3D N-doped graphene prepared without using phosphine

[EN] Development of efficient and stable electrodes for hydrogen and oxygen evolution from water constituted of abundant elements and prepared by sustainable and scalable procedures is of considerable importance for producing green hydrogen from renewable electricity. Herein, a method for the preparation of Ni2P, Fe2P, and FeP supported on N-doped graphene (NiP/NG and FeP/NG) is reported. The procedure uses metal salts, phosphorous oxide, and chitosan as precursors of metal phosphide and N-doped graphene, avoiding the use of undesirable and hazardous precursors, such as PH3 or NaH2PO2, and rendering a material with a strong metal phosphide-graphene interaction. Moreover, NiP/NG and FeP/NG electrodes are demonstrated to be more efficient than the benchmark catalysts Pt/C and RuO2, for hydrogen evolution reaction and oxygen evolution reaction, respectively, at a large current density (300 mA/cm(2)). In addition, water electrolysis was carried out using NiP/NG//FeP/NG electrodes, also demonstrating improved efficiency and stability compared with Pt/C//RuO2 at a current density (400 mA/cm(2)) near industrial requirements.Financial support by the "MCIN/AEI/10.13039/501100011033/y por FEDER Una manera de hacer Europa'' (RTI2018-098237-B-C21) and Generalitat Valenciana (Prometeo 2021-038) are gratefully acknowledged. The European Union project H2020-LC-SC3-2020-RES-RIA "EcoFuel''(grant agreement 101006701) is also gratefully acknowledged. J.H. thanks the Chinese Scholarship Council for doctoral fellowship. L.P. also thanks the Generalitat Valenciana for a Grisolia postgraduate scholarship.Hu, HJ.; Peng, L.; Primo Arnau, AM.; Albero-Sancho, J.; García Gómez, H. (2022). High-current water electrolysis performance of metal phosphides grafted on porous 3D N-doped graphene prepared without using phosphine. Cell Reports (Online). 3(5):1-16. https://doi.org/10.1016/j.xcrp.2022.1008731163

Extracellular Vesicles-Mediated Bio-Orthogonal Catalysis in Growing Tumors

Several studies have reported the successful use of bio-orthogonal catalyst nanoparticles (NPs) for cancer therapy. However, the delivery of the catalysts to the target tissues in vivo remains an unsolved challenge. The combination of catalytic NPs with extracellular vesicles (EVs) has been proposed as a promising approach to improve the delivery of therapeutic nanomaterials to the desired organs. In this study, we have developed a nanoscale bio-hybrid vector using a CO-mediated reduction at low temperature to generate ultrathin catalytic Pd nanosheets (PdNSs) as catalysts directly inside cancer-derived EVs. We have also compared their biodistribution with that of PEGylated PdNSs delivered by the EPR effect. Our results indicate that the accumulation of PdNSs in the tumour tissue was significantly higher when they were administered within the EVs compared to the PEGylated PdNSs. Conversely, the amount of Pd found in non-target organs (i.e., liver) was lowered. Once the Pd-based catalytic EVs were accumulated in the tumours, they enabled the activation of a paclitaxel prodrug demonstrating their ability to carry out bio-orthogonal uncaging chemistries in vivo for cancer therapy

Photocatalytic Overall Water Splitting Activity of Templateless Structured Graphitic Nanoparticles Obtained from Cyclodextrins

[EN] Pyrolysis of alpha-, beta-, and gamma-cyclodextrins at 900 degrees C under Ar forms porous 3D graphitic carbon nanoparticles with remarkable crystallinity, in which the pore dimensions range from 0.74 to 1.1 nm in the ultra/micropore range as determined by N-2, Ar, and CO2 adsorption. These materials behave as semiconductors with the potential energy of the conduction and valence bands being remarkably dependent in as much as 0.57 eV on the dimensions of the micropores. The photogeneration of electrons and holes was confirmed by photodeposition of Pt (electrons) and PbO2 (holes) nanoparticles by reduction and oxidation, respectively. Importantly, these 3D porous graphitic carbons generate H-2 and O-2 from H2O in the absence of any metal cocatalyst. Theoretical calculations at the DFT level confirm in models the influence of the dimensions of the pores, the presence of defects, and residual oxygen on the band energy and that the occurrence of H2O dissociation is favored inside the pores by a confinement effect. Considering the interest in developing metal-free photocatalyst, the present results show the possibility to tune the band alignment of porous carbon semiconductors by appropriate selection of precursors and the convenient generation of defects.Financial support by the Spanish Ministry of Science and Innovation (Severo Ochoa and CTQ2018-98237-CO2-1) and Generalitat Valenciana (Prometeo 2017-083) is gratefully acknowledged. We also thank the Center of Supercomputing of Galicia (CESGA) for the computational facilities. A.P. thanks the Spanish Ministry of Science and Innovation for a Ramon y Cajal research associate contract.Peng, Y.; Rendon-Patiño, A.; Franconetti, A.; Albero-Sancho, J.; Primo Arnau, AM.; García Gómez, H. 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