Scientific Papers in SCI
2022
2022
Materiales de Diseño para la Energía y Medioambiente
Iron-catalyzed graphitization for the synthesis of nanostructured graphitic carbons
Hunter, RD; Ramirez-Rico, J; Schnepp, ZJournal of Materials Chemistry A, 10 (2022) 4489-4516
Show abstract ▽
![](https://icms.us-csic.es/sites/icms.us-csic.es/files/Ram-1.png)
Carbons are versatile and diverse materials that have numerous applications across energy and environmental sciences. Carbons with a graphitic structure are particularly appealing due to their high chemical stability, large surface areas and high thermal and electronic conductivity. Numerous methods exist to produce nanostructured graphitic carbons but some of these can be energy-intensive and/or have problems with scalability. One option that is being increasingly explored is the process of iron-catalyzed graphitization. This simply involves the pyrolysis of carbon-rich precursors in the presence of an iron catalyst and has been used to produce carbons with a wide range of structures and properties. This review will examine the current field of iron-catalyzed graphitization, with a focus on molecular organic or biomass precursors. Bio-derived precursors are particularly attractive as a potential option for sustainable production of graphitic carbons. We start with a brief introduction to some key carbon structures, the current applications in which they are employed and some of the key methods that have been developed to produce nanostructured graphitic carbons. We will then review the history of catalytic graphitization before evaluating the wide range of conditions and precursors that have been employed in catalytic graphitization. Finally, this review will investigate the current challenges facing iron-catalyzed graphitization, looking particularly at the limitations of the current understanding of the mechanistic aspects of graphitization, with a view to outlining where research in this field might progress.
February, 2022 | DOI: 10.1039/d1ta09654k
Nanotecnología en Superficies y Plasma
Plasma assisted CO2 dissociation in pure and gas mixture streams with a ferroelectric packed-bed reactor in ambient conditions
Navascues, P; Cotrino, J; Gonzalez-Elipe, AR; Gomez-Ramirez, AChemical Engineering Journal, 430 (2022) 133066
Show abstract ▽
![](https://icms.us-csic.es/sites/icms.us-csic.es/files/1-s2_334.png)
Carbon dioxide decomposition is a challenging target to combat climate change. Nonthermal plasmas are advantageous for this purpose because they operate at ambient conditions and can be easily scaled-up. In this study, we attempt the CO2 splitting into CO and O-2 in a parallel plate packed-bed plasma reactor moderated with Lead Zirconate Titanate (PZT) as fermelectric component, achieving conversion rates and energy efficiencies higher than those obtained with BaTiO3 in our experimental device. The analysis of the reaction mechanisms with optical emission spectroscopy under various operating conditions has shown a direct correlation between energy efficiency and intensity of CO* emission bands. These results and those obtained with a LiNbO3 plate placed onto the active electrode suggest that high temperature electrons contribute to the splitting of CO2 through an enhancement in the formation of CO2+ intermediate species. Results obtained for CO2 + O-2 mixtures confirm this view and suggest that back recombination processes involving CO and O-2 may reduce the overall splitting efficiency. The study of mixtures of CO2 and dry air has proved the capacity of fermelectric packed-bed reactors to efficiently decompose CO2 with no formation of harmful NxOy subproducts in conditions close to those in real facilities. The found enhancement in energy efficiency with respect to that found for the pure gas decomposition supports that new reaction pathways involving nitrogen molecules are contributing to the dissociation reaction. We conclude that PZT moderated packed-bed plasma reactors is an optimum alternative for the decompositon of CO2 in real gas flows and ambient conditions.
February, 2022 | DOI: 10.1016/j.cej.2021.133066
Materiales Ópticos Multifuncionales
Optoelectronic Devices Based on Scaffold Stabilized Black-Phase CsPbI3 Nanocrystals
Romero-Perez, C; Rubino, A; Calio, L; Calvo, ME; Miguez, HAdvanced Optical Materials (2022) 2102112
Show abstract ▽
The optoelectronic properties of lead halide perovskites are intimately related to their crystalline phase. For the case of cesium lead iodide (CsPbI3) several polymorphs meet the Goldschmidt tolerance factor, which determines their stability, and form broad band absorber and luminescent phases. However, at room temperature none of them are stable, which prevents their use in optoelectronics. In this work, bare CsPbI3 nanocrystals are synthesized in the sub-10 nm range in the "black", light emitting, crystalline phase, using a pore controlled SiO2 matrix that limits crystal size and confers a certain degree of strain that favors their stability. Quantum confinement effects allow the tuning of the optical properties of the CsPbI3 nanocrystals by means of the crystal size. Their suitability as optoelectronic materials is demonstrated by building scaffold supported CsPbI3 quantum dot based photovoltaic and light emitting devices.
January, 2022 | DOI: 10.1002/adom.202102112
Reactividad de Sólidos
Effect of Steam Injection during Carbonation on the Multicyclic Performance of Limestone (CaCO3) under Different Calcium Looping Conditions: A Comparative Study
Troya, JJA; Moreno, V; Sánchez-Jiménez, PE; Perejon, A; Valverde, JM; Perez-Maqueda, LAACS Sustanaible Chemistry & Engineering, 10 (2022) 850-859
Show abstract ▽
![](https://icms.us-csic.es/sites/icms.us-csic.es/files/sc1c06314_0012.png)
This study explores the effect of steam addition during carbonation on the multicyclic performance of limestone under calcium looping conditions compatible with (i) CO2 capture from postcombustion gases (CCS) and with (ii) thermochemical energy storage (TCES). Steam injection has been proposed to improve the CO2 uptake capacity of CaO-based sorbents when the calcination and carbonation loops are carried out in CCS conditions: at moderate carbonation temperatures (similar to 650 degrees C) under low CO2 concentration (typically similar to 15% at atmospheric pressure). However, the recent proposal of calcium-looping as a TCES system for integration into concentrated solar power (CSP) plants has aroused interest in higher carbonation temperatures (similar to 800-850 degrees C) in pure CO2. Here, we show that steam benefits the multicyclic behavior in the milder conditions required for CCS. However, at the more aggressive conditions required in TCES, steam essentially has a neutral net effect as the CO2 uptake promoted by the reduced CO2 partial pressure but also is offset by the substantial steam-promoted mineralization in the high temperature range. Finally, we also demonstrate that the carbonation rate depends exclusively on the partial pressure of CO2, regardless of the diluting gas employed.
January, 2022 | DOI: 10.1021/acssuschemeng.1c06314
Química de Superficies y Catálisis
Structured and micro-structured catalysts: A fascinating future for a sustainable world – A special issue in tribute to the careers of Professors Mario Montes and José Antonio Odriozola
M.A.Centeno; L.M.Gandía; F.Romero-Sarria; O.SanzCatalysis Today, 383 (2022) 1-4
Show abstract ▽
- ‹ previous
- 67 of 420
- next ›