Exciton tuning and strain imaging in WS2supported on PDMS micropillars

Since the raise of 2D materials, significant research has been dedicated to their strain-dependent electronic and mechanical properties. In this work, we studied exciton energies and low-frequency phonon modes in CVD-grown mono- and few-layer WS2 transferred on PDMS micropillars. The modification of the band structure under strain was investigated by photoluminescence (PL) spectroscopy at room temperature. Machine learning (ML) methods were used to analyze the PL spatial maps and facilitate the spectral deconvolution. For monolayer (1L) WS2, red shift in the exciton energy was detected as a function of the position, which was ascribed to the presence of residual strain. For three-layer (3L) strained WS2, a significant increase in the PL intensity corresponding to direct (K-K) band transition together with a change of exciton energy was observed. From the PL spectra, strain distribution maps were extracted for both studied samples, which strongly resembled the ML clustering results. Finally, the low-frequency Raman modes of WS2 were studied on both Si/SiO2 and PDMS substrates and no significant change of their frequency was observed for the 3L-WS2.This work has been supported by the Severo Ochoa Program (No. SEV-2017-0706 funded by MCIN/AEI/10.13039/501100011033), by the Spanish Ministry of Economy and Competitiveness (MINECO) under Contract Nos. PGC2018-095032-B-I00 and PID2021-124568NB-I00, and by the CERCA Programme/Generalitat de Catalunya. The authors acknowledge the European Union's H2020 FET Proactive Project TOCHA (Grant No. 824140) and the ERC-AdG Project LEIT (Grant No. 885689)

Exploring the Potential of Green Hydrogen Production and Application in the Antofagasta Region of Chile

Green hydrogen is gaining increasing attention as a key component of the global energy transition towards a more sustainable industry. Chile, with its vast renewable energy potential, is well positioned to become a major producer and exporter of green hydrogen. In this context, this paper explores the prospects for green hydrogen production and use in Chile. The perspectives presented in this study are primarily based on a compilation of government reports and data from the scientific literature, which primarily offer a theoretical perspective on the efficiency and cost of hydrogen production. To address the need for experimental data, an ongoing experimental project was initiated in March 2023. This project aims to assess the efficiency of hydrogen production and consumption in the Atacama Desert through the deployment of a mobile on-site laboratory for hydrogen generation. The facility is mainly composed by solar panels, electrolyzers, fuel cells, and a battery bank, and it moves through the Atacama Desert in Chile at different altitudes, from the sea level, to measure the efficiency of hydrogen generation through the energy approach. The challenges and opportunities in Chile for developing a robust green hydrogen economy are also analyzed. According to the results, Chile has remarkable renewable energy resources, particularly in solar and wind power, that could be harnessed to produce green hydrogen. Chile has also established a supportive policy framework that promotes the development of renewable energy and the adoption of green hydrogen technologies. However, there are challenges that need to be addressed, such as the high capital costs of green hydrogen production and the need for supportive infrastructure. Despite these challenges, we argue that Chile has the potential to become a leading producer and exporter of green hydrogen or derivatives such as ammonia or methanol. The country’s strategic location, political stability, and strong commitment to renewable energy provide a favorable environment for the development of a green hydrogen industry. The growing demand for clean energy and the increasing interest in decarbonization present significant opportunities for Chile to capitalize on its renewable energy resources and become a major player in the global green hydrogen market.We acknowledge financial support from for Gobierno Regional de Antofagasta and FIC-R project código BIP: 40033431-0. CICITEM is supported by the Gobierno regional de Antofagasta. ICN2 is supported by the Severo Ochoa program from the Spanish Research Agency (AEI, grant no. SEV-2017-0706) and by the CERCA Programme/Generalitat de Catalunya.Peer reviewe

Dataset related to the publication "Thermal properties of nanocrystalline silicon nanobeams"

Versión 1. El artículo en el que se basan los datos fue publicado en Advanced Functional Materials 32(4): 2105767 (2022)Dataset contains the raw data from which the graphs in paper "Thermal properties of nanocrystalline silicon nanobeams".Grants: European Commission: PHENOMEN - All-Phononic circuits Enabled by Opto-mechanics (713450) NANOPOLY - Artificial permittivity and permeability engineering for future generation sub wavelength analogue integrated circuits and systems (829061)Peer reviewe