Frontiers in Energy最新文献

Due to its fascinating and tunable optoelectronic properties, semiconductor nanomaterials are the best choices for multidisciplinary applications. Particularly, the use of semiconductor photocatalysts is one of the promising ways to harness solar energy for useful applications in the field of energy and environment. In recent years, metal oxide-based tailored semiconductor photocatalysts have extensively been used for photocatalytic conversion of carbon dioxide (CO₂) into fuels and other useful products utilizing solar energy. This is very significant not only from renewable energy consumption but also from reducing global warming point of view. Such current research activities are promising for a better future of society. The present mini-review is focused on recent developments (2–3 years) in metal oxide semiconductor hybrid photocatalysts-based photo-electrochemical conversion of CO₂ into fuels and other useful products. First, general mechanism of photo-electrochemical conversion of CO₂ into fuels or other useful products has been discussed. Then, various metal oxide-based emerging hybrid photocatalysts including tailoring of their morphological, compositional, and optoelectronic properties have been discussed with emphasis on their role in enhancing photo-electrochemical efficienty. Afterwards, mechanism of their photo-electrochemical reactions and applications in CO₂ conversion into fuels/other useful products have been discussed. Finally, challenges and future prospects have been discussed followed by a summary.

The use of two-dimensional (2D) layered metal-organic frameworks (MOFs) as self-sacrificial templates has been proven to be a successful method to create high-efficiency Selenium (Se)-containing electrocatalysts for overall water splitting. Herein, two strategies are then utilized to introduce Se element into the Co–Fe MOF, one being the etching of as-prepared MOF by SeO₂ solution, and the other, the replacing of SCN⁻ with SeCN⁻ as the construction unit. The electrochemical activity of the pristine 2D MOF and their calcinated derivatives for catalyzing the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is evaluated and further discussed. It is found that the effect of introducing Se on improving electrochemical catalytic activity is significant for the HER process. Specifically, the calcinated derivative in the replacing method exhibits an overpotential of 235 mV for HER and 270 mV for OER at a current density of 10 mA/cm². For comparing the two methods of introducing Se element into MOF, similar electrocatalytic activity can be achieved on the their calcinated derivatives. The high electrochemical performance of 2D CoFe-MOF derivatives may be resulted from the unique 2D hierarchical porous structure and strong synergistic effect between different components in the material.

Great progress has been made in the electrochromic (EC) technology with potential applications in various fields. As one of the most promising EC materials, Prussian blue (PB) has attracted great attention due to its excellent EC performance, such as low cost, easy synthesis, rich color states, chemical stability, suitable redox potential, and fast color-switching kinetics. This review summarizes the recent progress in PB electrodes and devices, including several typical preparation techniques of PB electrodes, as well as the recent key strategies for enhancing EC performance of PB electrodes. Specifically, PB-based electrochromic devices (ECDs) have been widely used in various fields, such as smart windows, electrochromic energy storage devices (EESDs), wearable electronics, smart displays, military camouflage, and other fields. Several opportunities and obstacles are suggested for advancing the development of PB-based ECDs. This comprehensive review is expected to offer valuable insights for the design and fabrication of sophisticated PB-based ECDs, enabling their practical integration into real-world applications.

The electrochemistry of cathode materials for sodium-ion batteries differs significantly from lithium-ion batteries and offers distinct advantages. Overall, the progress of commercializing sodium-ion batteries is currently impeded by the inherent inefficiencies exhibited by these cathode materials, which include insufficient conductivity, slow kinetics, and substantial volume changes throughout the process of intercalation and deintercalation cycles. Consequently, numerous methodologies have been utilized to tackle these challenges, encompassing structural modulation, surface modification, and elemental doping. This paper aims to highlight fundamental principles and strategies for the development of sodium transition metal oxide cathodes. Specifically, it emphasizes the role of various elemental doping techniques in initiating anionic redox reactions, improving cathode stability, and enhancing the operational voltage of these cathodes, aiming to provide readers with novel perspectives on the design of sodium metal oxide cathodes through the doping approach, as well as address the current obstacles that can be overcome/alleviated through these dopant strategies.

Exploring advanced platinum (Pt)-based electrocatalysts is vital for the widespread implementation of proton exchange membrane fuel cells (PEMFCs). Morphology control represents an effective strategy to optimize the behavior of Pt catalysts. In this work, an attempt is made to comprehensively review the effect of morphology control on the catalytic behavior of catalysts in the oxygen reduction reaction (ORR). First, the fundamental physicochemical changes behind morphology control, including exposing more active sites, generating appropriate lattice strains, and forming different crystalline surfaces, are highlighted. Then, recently developed strategies for tuning the morphologies of electrocatalysts, including core-shell structures, hollow structures, nanocages, nanowires, and nanosheets, are comprehensively summarized. Finally, an outlook on the future development of morphology control of Pt catalysts is presented, including rational design strategies, advanced in situ characterization techniques, novel artificial intelligence, and mechanical learning. This work is intended to provide valuable insights into designing the morphology and technological innovation of efficient redox electrocatalysts in fuel cells.

Proton exchange membrane fuel cells (PEMFCs) are playing irreplaceable roles in the construction of the future sustainable energy system. However, the insufficient performance of platinum (Pt)-based electrocatalysts for oxygen reduction reaction (ORR) hinders the overall efficiency of PEMFCs. Engineering the surface strain of catalysts is considered an effective way to tune their electronic structures and therefore optimize catalytic behavior. In this paper, insights into strain engineering for improving Pt-based catalysts toward ORR are elaborated in detail. First, recent advances in understanding the strain effects on ORR catalysts are comprehensively discussed. Then, strain engineering methodologies for adjusting Pt-based catalysts are comprehensively discussed. Finally, further information on the various challenges and potential prospects for strain modulation of Pt-based catalysts is provided.