Major research efforts are being carried out for the technological advancement to an energetically sustainable society. However, for the full commercial integration of electrochemical energy storage devices, not only materials with higher performance should be designed and manufactured but also more competitive production techniques need to be developed.
The laser processing technology is well extended at the industrial sector for the versatile and high throughput modification of a wide range of materials. In this work, a method based on laser processing is presented for the fabrication of hybrid electrodes composed of graphene nanowalls (GNWs) coated with different transition-metal oxide nanostructures for electrochemical capacitor (EC) applications. GNW/stainless steel electrodes grown by plasma enhanced chemical vapor deposition were decorated with metal oxide nanostructures by means of their laser surface processing while immersed in aqueous organometallic solutions. The pseudocapacitive nature of the laser-induced crystallized oxide materials prompted an increase of the GNW electrodes' capacitance by 3 orders of magnitude, up to ca. 28 F/cm3 at 10 mV/s, at both the positive and negative voltages. Finally, asymmetric aqueous and solid-state ECs revealed excellent stability upon tens of thousands of charge-discharge cycles.
Sustainable energy conversion & storage systems
Boost of Charge Storage Performance of Graphene Nanowall Electrodes by Laser-Induced Crystallization of Metal Oxide Nanostructures
Yasmín Esqueda-Barrón, Angel Pérez Del Pino, Pablo García Lebière, Arevik Musheghyan-Avetisyan, Enric Bertran-Serra, Enikö György, Constantin Logofatu
ACS Appl Mater Interfaces. 21;13(15):17957-17970. Doi: 10.1021/acsami.1c00951. 2021 Erratum in: ACS Appl Mater Interfaces. 2021 May 20;: PMID: 33843185.
The discovery of novel high-performing materials such as non-fullerene acceptors and low band gap donor polymers underlines the steady increase of record efficiencies in organic solar cells witnessed during the past years. Nowadays, the resulting catalogue of organic photovoltaic materials is becoming unaffordably vast to be evaluated following classical experimentation methodologies: their requirements in terms of human workforce time and resources are prohibitively high, which slows momentum to the evolution of the organic photovoltaic technology.
Recently synthesized hexagonal group IV materials are a promising platform to realize efficient light emission that is closely integrated with electronics. A high crystal quality is essential to assess the intrinsic electronic and optical properties of these materials unaffected by structural defects. Here, we identify a previously unknown partial planar defect in materials with a type I3 basal stacking fault and investigate its structural and electronic properties.
The advanced materials industry is one of the leading technology sectors worldwide. The development of such materials is at the core of the technological innovations and has been possible in the last century thanks to the transition from “observational” science to “control” science.
Transition metal carbides have gathered increasing attention in energy and electrochemistry applications, mainly due to their high structural and physicochemical properties. Their high refractory properties have made them an ideal candidate coating technology and more recently their electronic similarity to the platinum group has expanded their use to energy and catalysis. Here, we demonstrate that the nanostructuring and stoichiometry control of the highest melting point material to this date (Ta-Hf-C) results in outstanding electrochemical stability.
There is an increasing interest in synthetic systems that can execute bioinspired chemical reactions without requiring the complex structures that characterize enzymes in their components. The hierarchical self-assembly of peptides provides a means to create catalytic microenvironments. Ideally, as it occurs in enzymes, the catalytic activity of peptide nanostructures should be reversibly regulated. In a typical enzyme mimetic design, the peptide’s self-assembling and catalytic activities are segregated into different regions of the sequence.