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Technologically useful and robust graphene-based interfaces for devices require the introduction of highly selective, stable, and covalently bonded functionalities on the graphene surface, whilst essentially retaining the electronic properties of the pristine layer. This work demonstrates that highly controlled, ultrahigh vacuum covalent chemical functionalization of graphene sheets with a thiol-terminated molecule provides a robust and tunable platform for the development of hybrid nanostructures in different environments. We employ this facile strategy to covalently couple two representative systems of broad interest: metal nanoparticles, via S–metal bonds, and thiol-modified DNA aptamers, via disulfide bridges. Both systems, which have been characterized by a multitechnique approach, remain firmly anchored to the graphene surface even after several washing cycles. Atomic force microscopy images demonstrate that the conjugated aptamer retains the functionality required to recognize a target protein. This methodology opens a new route to the integration of high-quality graphene layers into diverse technological platforms, including plasmonics, optoelectronics, or biosensing. With respect to the latter, the viability of a thiol-functionalized chemical vapor deposition graphene-based solution-gated field-effect transistor array was assessed., This work was supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement No 696656 (Graphene Flagship-core 1) and no 785219 (Graphene Flagship −core 2); UE FP7 ideas: ERC (grant ERC-2013-SYG-610256 Nanocosmos) and Spanish MINECO grants MAT2014-54231-C4-1-P, MAT2014-54231-C4-4-P, MAT2017-85089-C2-1-R, MAT2014-59772-C2-2-P, and BIO2016-79618-R (funded by EU under the FEDER programme), as well as the Nanoavansens program from the Community of Madrid (S2013/MIT-3029). This work has made use of the Spanish ICTS Network MICRONANOFABS partially supported by MINECO and also the ICTS NANBIOSIS, more specifically the Micro-Nano Technology Unit of the CIBER in Bioengineering, Biomaterials & Nanomedicine (CIBER-BBN) at the IMB-CNM. We are grateful to Matthias Muntwiler for his assistance with experiments in the PEARL beamline in the SLS facility. Finally, we acknowledge the TEM and ICP services at the CNB and ICMM institutes, respectively. CSS acknowledges the MINECO for a Juan de la Cierva Incorporación grant (IJCI-2014-19291). M. Marciello is grateful to the Comunidad de Madrid (CM) and European Social Fund (ESF) for supporting her research work through the I+D Collaborative Programme in Biomedicine NIETO-CM (B2017-BMD3731).

[EN] The report of the Meissner effect in annealed samples of K3Tp (Tp = p-terphenyl) above 120 K has raised the interest in this deceptively simple material concerning superconductivity. We have investigated the structural integrity of the Tp framework in the annealed samples of KxTp at increasing processing time and temperature T. Our experimental studies show that both K2Tp and K3Tp mixing stoichiometries have identical Raman (solid state) and UV–vis (1,2-dimethoxyethane solution) spectra, being consistent with the molecular dianion by density functional theory and time-dependent density functional theory simulations. Magnetization vs T plots show no signs of superconductivity and neither do conductance vs T plots. Searching for potentially active minor byproducts formed during thermal processing, the role of K-doped poly(p-phenylene) has been examined, but it does not seem to explain the reported effects either. Further efforts are needed to explain the nature of this elusive phenomenon., Financial support by the Spanish Ministry of Economy and Competitiveness (FIS2015-64222-C2-1-P, MAT2014-52405-C2-2-R, and MAT2016-78625-C2-1-2-P), the Generalitat Valenciana (Grant PROMETEO/2017/139), and the University of Alicante (VIGROB-285) is gratefully acknowledged. M.C. thanks the VIDI of the University of Alicante for a predoctoral grant. A.G. greatly appreciates the computational resources provided by the Department of Applied Physics of the University of Alicante.

The design of artificial vortex pinning landscapes is a major goal toward large scale applications of cuprate superconductors. Although disordered nanometric inclusions have shown to modify their vortex phase diagram and to produce enhancements of the critical current (MacManus-Driscoll, J. L.; Foltyn, S. R.; Jia, Q. X.; Wang, H.; Serquis, A.; Civale, L.; Maiorov, B.; Hawley, M. E.; Maley, M. P.; Peterson, D. E. Nat. Mater. 2004, 3, 439?443 and Yamada, Y.; Takahashi, K.; Kobayashi, H.; Konishi, M.; Watanabe, T.; Ibi, A.; Muroga, T.; Miyata, S.; Kato, T.; Hirayama, T.; Shiohara, Y. Appl. Phys. Lett. 2005, 87, 1-3), the effect of ordered oxide nanostructures remains essentially unexplored. This is due to the very small nanostructure size imposed by the short coherence length, and to the technological difficulties in the nanofabrication process. Yet, the novel phenomena occurring at oxide interfaces open a wide spectrum of technological opportunities to interplay with the superconductivity in cuprates. Here, we show that the unusual long-range suppression of the superconductivity occurring at the interface between manganites and cuprates affects vortex nucleation and provides a novel vortex pinning mechanism. In particular, we show evidence of commensurate pinning in YBCO films with ordered arrays of LCMO ferromagnetic nanodots. Vortex pinning results from the proximity induced reduction of the condensation energy at the vicinity of the magnetic nanodots, and yields an enhanced friction between the nanodot array and the moving vortex lattice in the liquid phase. This result shows that all-oxide ordered nanostructures constitute a powerful, new route for the artificial manipulation of vortex matter in cuprates., Work at UCM supported by grants MAT2014-52405-C02-01 and Consolider Ingenio 2010-CSD2009-00013 (Imagine), by CAM through grant CAM S2013/MIT-2740. Work done at ICMM supported by Spanish MINECO (Ministry for Economy and Competitiveness) grants MAT2011-27470-C02-02, MAT2014-52405-C02-02, and Consolider Ingenio CSD2009-00013 (Imagine). J.V. acknowledges European Research Council, ERC, grant No. 647100 “SUSPINTRONICS”.

Ti-doped BiFeO3 ceramics prepared by a mixed-oxide route were structurally characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM), giving evidence of the formation of an inner structure at the nanometric scale. The observed nanograins are separated by Ti-rich areas that originate due to the tendency of the titanium dopant to segregate from the perovskite lattice. Such a peculiar nanostructure is responsible for the changes produced in both the electrical and the magnetic properties of BiFeO3 upon titanium doping: the Ti-rich interfaces act as resistive layers that increase the direct-current (dc) resistivity of the material, while the existence of structural domains in the scale of tens of nanometers causes a ferrimagnetic-like behavior with a huge coercive field (on the order of 20 kOe), even at room temperature., This work has been conducted within the CICYT MAT 2010-16614, CSD2009-00013, and MAT-27470-C02-02 projects. M.S.B. also acknowledges the Spanish Ministry of Education for the financial support (FPU Program, No. AP2008-00053). T.J. acknowledges the JAE-Doc contract of the Spanish National Research Council (CSIC) and European Science Foundation (ESF). M.P. also acknowledges the Ramón y Cajal Program of MINECO for the financial support.