Departamento de Física Aplicada
Universidad de Córdoba
Dolores G. Gil-Gavilán, Daniel Cosano, Juan Amaro-Gahete, Miguel Castillo-Rodríguez, Dolores Esquivel, José R. Ruiz, and Francisco J. Romero-Salguero MDPI AG
Carbon dioxide is the main gas responsible for the greenhouse effect. Over the last few years, the research focus of many studies has been to transform CO2 into valuable products (CO, HCOOH, HCHO, CH3OH and CH4), since it would contribute to mitigating global warming and environmental pollution. Layered double hydroxides (LDHs) are two-dimensional materials with high CO2 adsorption capacity and compositional flexibility with potential catalytic properties to be applied in CO2 reduction processes. Herein, Zn-Cr LDH-based materials with different metal ratio and interlayer anions, i.e., chloride (Cl−), graphene quantum dots (GQDs), sodium dodecyl sulfate (SDS) and sodium deoxycholate (SDC), have been prepared by a co-precipitation method and characterized by different techniques. The influence of the interlayer inorganic and organic anions and the metal ratio on the application of Zn-Cr LDHs as catalysts for the photocatalytic CO2 reduction reaction under visible light irradiation is unprecedentedly reported. The catalytic tests have been carried out with Ru(bpy)32+ as photosensitizer (PS) and triethanolamine as sacrificial electron donor (ED) at λ = 450 nm. All LDHs materials exhibited good photocatalytic activity towards CO. Among them, LDH3-SDC showed the best catalytic performance, achieving 10,977 µmol CO g−1 at 24 h under visible light irradiation with a CO selectivity of 88%. This study provides pertinent findings about the modified physicochemical features of Zn-Cr LDHs, such as particle size, surface area and the nature of the interlayer anion, and how they influence the catalytic activity in CO2 photoreduction.
Shawkat Imam Shakil, Leandro González-Rovira, Leticia Cabrera-Correa, Juan de Dios López-Castro, Miguel Castillo-Rodríguez, F. Javier Botana, and Meysam Haghshenas Elsevier BV
Dolores G. Gil-Gavilán, Daniel Cosano, Miguel Castillo-Rodríguez, Gustavo de Miguel, Dolores Esquivel, César Jiménez-Sanchidrián, José R. Ruiz, and Francisco J. Romero-Salguero Elsevier BV
Raúl Rojas-Luna, Juan Amaro-Gahete, Dolores G. Gil-Gavilán, Miguel Castillo-Rodríguez, César Jiménez-Sanchidrián, José Rafael Ruiz, Dolores Esquivel, and Francisco José Romero-Salguero Elsevier BV
M. Carmen Herrera-Beurnio, Francisco J. López-Tenllado, Jesús Hidalgo-Carrillo, Juan Martín-Gómez, Rafael Estévez, Miguel Castillo-Rodríguez, Gustavo de Miguel, Francisco J. Urbano, and Alberto Marinas Elsevier BV
Juan Martín-Gómez, Juan Carlos Escamilla, Jesús Hidalgo-Carrillo, Francisco J. López-Tenllado, Rafael C. Estévez-Toledano, M. Carmen Herrera-Beurnio, Miguel Castillo-Rodríguez, Francisco J. Urbano, and Alberto Marinas Elsevier BV
Leticia Cabrera-Correa, Leandro González-Rovira, Juan de Dios López-Castro, Miguel Castillo-Rodríguez, and F. Javier Botana Elsevier BV
Raúl Rojas-Luna, Miguel Castillo-Rodríguez, José R. Ruiz, César Jiménez-Sanchidrián, Dolores Esquivel, and Francisco J. Romero-Salguero Royal Society of Chemistry (RSC)
Novel artificial photosynthetic systems based on PMOs containing surface Ru- and Ir-complexes as photosensitizers and Pt nanoparticles as catalysts act as efficient heterogeneous photocatalysts in the hydrogen evolution reaction.
Mewin Vincent, Venkata Sai Avvaru, Miguel Castillo Rodríguez, Maciej Haranczyk, and Vinodkumar Etacheri Elsevier BV
Wenliang Feng, Venkata Sai Avvaru, Rudi Ruben Maça, Steven J. Hinder, Miguel Castillo Rodríguez, and Vinodkumar Etacheri American Chemical Society (ACS)
Sodium-ion hybrid capacitors (SHCs) have attracted great attention owing to the improved power density and cycling stability in comparison with sodium-ion batteries. Nevertheless, the energy density (<100 Wh·kg-1) is usually limited by low specific capacity anodes (<150 mAh·g-1) and "kinetics mismatch" between the electrodes. Hence, we report a high energy density (153 Wh·kg-1) SHC based on a highly pseudocapacitive interface-engineered 3D-CoO-NrGO anode. This high-performance anode (445 mAh·g-1 @0.025 A·g-1, 135 mAh·g-1 @5.0 A·g-1) consists of CoO (∼6 nm) nanoparticles chemically bonded to the NrGO network through Co-O-C bonds. Exceptional pseudocapacitive charge storage (up to ∼81%) and capacity retention (∼80% after 5000 cycles) are also identified for this SHC. Excellent performance of the 3D-CoO-NrGO anode and SHC is owing to the synergistic effect of the CoO conversion reaction and pseudocapacitive sodium-ion storage induced by numerous Na2O/Co/NrGO nanointerfaces. Co-O-C bonds and the 3D microstructure facilitating efficient strain relaxation and charge-transfer correspondingly are also identified as vital factors accountable for the excellent electrochemical performance. The interface-engineering strategy demonstrated provides opportunities to design high-performance transition metal oxide-based anodes for advanced SHCs.
Venkata Sai Avvaru, Ivan Jimenez Fernandez, Wenliang Feng, Steven J. Hinder, Miguel Castillo Rodríguez, and Vinodkumar Etacheri Elsevier BV
M.A. Monclús, L. Yang, I. López-Cabañas, M. Castillo-Rodríguez, A. Zaman, J. Wang, E.I. Meletis, R. González-Arrabal, J. Llorca, and J.M. Molina-Aldareguía Elsevier BV
Qi Wang, Jing Zhang, Wen Shi, Miguel Castillo-Rodríguez, Dang Sheng Su, and De-Yi Wang Elsevier BV
Rudi Ruben Maça, Daniel Cíntora Juárez, Miguel Castillo Rodríguez, and Vinodkumar Etacheri Elsevier BV
Jaime S. Sanchez, Rudi Ruben Maça, Afshin Pendashteh, Vinodkumar Etacheri, Víctor A. de la Peña O'Shea, Miguel Castillo-Rodríguez, Jesus Palma, and Rebeca Marcilla Royal Society of Chemistry (RSC)
The electrocatalytic activity of the N-rGO/Co3O4 nanocomposites was tuned towards highly efficient bifunctional air-cathodes for Zn–Air batteries.
Lu Zhang, Wei Liu, Xin Wen, Jiayin Chen, Chenshou Zhao, Miguel Castillo-Rodríguez, Lingwei Yang, Xiu-Qin Zhang, Rui Wang, and De-Yi Wang Elsevier BV
Saúl Rubio, Rudi Ruben Maça, María J. Aragón, Marta Cabello, Miguel Castillo-Rodríguez, Pedro Lavela, José L. Tirado, Vinodkumar Etacheri, and Gregorio F. Ortiz Elsevier BV
Zhilin Liu, Ioannis Papadimitriou, Miguel Castillo-Rodríguez, Chuanyun Wang, Gustavo Esteban-Manzanares, Xiaoming Yuan, Hark H. Tan, Jon M. Molina-Aldareguía, and Javier Llorca American Chemical Society (ACS)
Taper-free InP twinning superlattice (TSL) nanowires with an average twin spacing of ~ 13 nm were grown along the zinc-blende close-packed  direction using metalorganic vapor phase epitaxy. The mechanical properties and fracture mechanisms of individual InP TSL nanowires in tension were ascertained by means of in situ uniaxial tensile tests in a transmission electron microscope. The elastic modulus, failure strain and tensile strength along the  were determined. No evidence of inelastic deformation mechanisms was found before fracture, that took place in a brittle manner along the twin boundary. The experimental results were supported by molecular dynamics simulations of the tensile deformation of the nanowires, which also showed that the fracture of twinned nanowires occurred in the absence of inelastic deformation mechanisms by the propagation of a crack from the nanowire surface along the twin boundary.
Qian Liu, Miguel Castillo-Rodríguez, Antonio Galisteo, Roberto Guzmán de Villoria, and José Torralba MDPI AG
Copper–graphite composites with 0–4 wt % graphite were fabricated by field-assisted hot pressing with the aim of studying the effect of graphite content on microhardness and tribological properties. Experimental results reveal that hardness decreases with the graphite content. Wear testing was carried out using a ball-on-disc tribometer with a normal load of 8 N at a constant sliding velocity of 0.16 m/s. The friction coefficient of composites decreases significantly from 0.92 to 0.29 with the increase in graphite content, resulting in a friction coefficient for the 4 wt % graphite composite that is 68.5% lower than pure copper. The wear rate first increases when the graphite content is 1 wt %; it then decreases as the graphite content is further increased until a certain critical threshold concentration of graphite, which seems to be around 3 wt %. Plastic deformation in conjunction with some oxidative wear is the wear mechanism observed in pure copper, while abrasive wear is the main wear mechanism in copper–graphite composites.
C.M. Cepeda-Jiménez, M. Castillo-Rodríguez, and M.T. Pérez-Prado Elsevier BV
Peikang Xia, F. Vercruysse, Roumen Petrov, Ilchat Sabirov, Miguel Castillo-Rodríguez, and Patricia Verleysen Elsevier BV
Ivan Lomakin, Miguel Castillo-Rodríguez, and Xavier Sauvage Elsevier BV
N. Ur Rahman, L. Capuano, A. van der Meer, M.B. de Rooij, D.T.A. Matthews, G. Walmag, M. Sinnaeve, A. Garcia-Junceda, M. Castillo, and G.R.B.E. Römer Elsevier BV
Miguel Castillo-Rodríguez, Antonio Muñoz, and Arturo Domínguez-Rodríguez Elsevier BV
Z. Liu, M.A. Monclús, L.W. Yang, M. Castillo-Rodríguez, J.M. Molina-Aldareguía, and J. LLorca Elsevier BV