Search

The escalating urgency to mitigate climate change and enhance energy security has prompted heightened exploration of hydrogen production via electrocatalysis as a viable alternative to conventional fossil fuels. Among the myriad of electrocatalysts under investigation, two-dimensional (2D) metal–organic frameworks (MOFs) stand out as a particularly appealing option. Their unique properties, including a large active specific surface area, distinctive pore structure, ample metal active sites, ultra-thin thickness, superior ion transport efficiency, fast electron transfer rate, and the ability to control the morphological synthesis, endow these frameworks with exceptional versatility and promising potential for electrocatalytic applications. In this review, we delineate the structural features and advantages of 2D MOFs and their derivatives. We proceed to summarize the latest advancements in the synthesis and utilization of these materials for electrocatalytic hydrogen evolution reactions (HER) and oxygen evolution reactions (OER). Finally, we scrutinize the potential and challenges inherent to 2D MOFs and their derivatives in practical applications, underscoring the imperative for continued research in this captivating field of electrocatalysis. [ABSTRACT FROM AUTHOR]

Photocatalysis is considered to be a green and environment‐friendly technology since it can convert solar energy into other types of chemical energies. Over the past several years, metal‐organic frameworks (MOFs)‐based photocatalysts have received remarkable research interest due to their unique morphology, high photocatalytic performance, good chemical stability, easy synthesis, and low cost. In this review, the synthetic strategies of developing MOFs‐based photocatalysts are first introduced. Second, the recent progress in the fabrication of various types of MOFs composites photocatalysts is summarized. Third, the different applications including hydrogen evolution reaction, oxygen evolution reaction, overall water splitting, nitrogen reduction reaction, carbon dioxide reduction reaction as well as photodegradation of organic pollutants of MOFs‐based photocatalysts are summed up. Finally, the challenges and some suggestions for the future development of MOFs‐ and their composites‐based photocatalysts are also highlighted. It is expected that this report will help researchers to systematically devise and develop highly efficient photocatalysts based on MOFs and their composites. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis of cactus-shaped CdS-Cu 9 S 5 heterostructure on copper foam (CdS-Cu 9 S 5 -CF) through a cost-effective strategy. The as-prepared CdS-Cu 9 S 5 -CF is demonstrated to be a highly efficient catalyst for photoelectrochemical (PEC) water splitting, and its high performance is attributed to its unique cactus-shaped structure, which provides abundant surface catalytic active sites, and numerous charge transfer channels, thereby enhancing the transport and separation of photoinduced charge carriers during the PEC process. The optimized 3% CdS-Cu 9 S 5 -CF (the mole ratio of CdS: Cu 9 S 5 = 3: 100) exhibits higher photocurrent density than those of pure Cu 9 S 5 and other CdS-Cu 9 S 5 -CF catalysts because the synergetic effects between Cu 9 S 5 and CdS can significantly inhibit the recombination of photoinduced charge carriers during the PEC process. We believe that the new synthetic route developed in this study will enable the facile preparation of metal sulfide-based catalysts for high-efficiency PEC water splitting. Unlabelled Image • The cactus-shaped CdS-Cu 9 S 5 heterostructure was successfully fabricated. • Such cactus-shaped structure can offer more carrier charges transfer channel. • PEC performance enhancement of Cu 9 S 5 through optimized the CdS content. [ABSTRACT FROM AUTHOR]

Abstract In this work, nanosheet-shaped CuS (NS CuS) is successfully grown on carbon cloth (CC) by a two-step route in combination with electrodeposition and hydrothermal treatment via in situ sulfidations of Cu 2 O and Cu with exposure to thiourea at 120 °C or 24 h. Transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffractometry are performed to characterize the microstructure, morphology, composition, and crystal structure of the NS CuS CC samples. The electrochemical measurements demonstrate that the synthesized NS CuS CC electrocatalysts possess outstanding oxygen evolution reaction (OER) performance and superior long-term durability in 1 M KOH electrolyte. In particular, the NS CuS CC synthesized via the electrodeposition process at an applied current of 1.5 mA shows a low overpotential for the OER (358 mV at 10 mA/cm2), which is close to that of commercial IrO 2 (346 mV at 10 mA/cm2). The exceptional OER property is ascribed to the NS CuS having a large surface area to offer abundant reaction active sites and to the CC network structures supplying more ions and charge transfer channels during the electrocatalytic process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchical CoS 2 /MoS 2 nanoflakes were successfully grown on graphene (CMSGr). • Hierarchical morphology provides more reaction sites and abundant charge transfer pathways. • The optimized CMSGr catalyst presents low overpotentials of 53 and 255 mV for HER and OER. • The optimized CMSGr catalyst shows a low voltage of 1.55 V for water splitting. Construction of cost-efficient and high-performance overall water splitting electrocatalysts for generating hydrogen and oxygen has recently received increasing research attention. Herein, hierarchical CoS 2 /MoS 2 (CMS) nanoflakes were successfully decorated on graphene (denoted as CMSGr) as an efficient electrocatalyst for overall water splitting. Owing to the distinct hierarchical flakes morphology, and optimized interfacial microenvironment between CoS 2 and MoS 2 , the fabricated CMSGr composites exhibit enhanced hydrogen and oxygen evolution reaction (HER/OER) activity. In particular, the optimized CMSGr-3 electrocatalyst presents the small overpotentials of 53 and 255 mV for HER and OER, and a low voltage of 1.55 V for overall water splitting in alkaline media under 10 mA cm−2. Theoretical calculations confirm that introducing CoS 2 into MoS 2 can greatly tune the electronic structure and optimize the adsorption energy during the water splitting. This work demonstrates that tuning the interfacial microenvironment of the binary metal sulfide composites is an effective route for developing high-performance water splitting electrocatalysts. [ABSTRACT FROM AUTHOR]

Recently, metal-organic framework (MOF)-derived composites have emerged as a promising class of materials for energy conversion systems due to their tunable pore size, large surface area, and high catalytic performance. In this review, the different types of synthesis approaches for MOF-derived composites are first summarized. Recent advances in the use of MOF-derived composites for various energy conversion applications, such as oxygen evolution reaction, hydrogen evolution reaction, overall water splitting, nitrogen reduction reaction, as well as oxygen reduction reaction, are summed up. Finally, some challenges and views for the future development of MOF-derived composites in the field of energy conversion systems are discussed. We hope this review will provide inspiration and guidance for the design and development of high-quality MOF-derived composites for energy conversion systems. [Display omitted] • The different types of synthesis approaches of MOF-derived composites are summarized. • Various energy conversion applications of MOF-derived composites are discussed. • Some challenges and views for the future development of MOF-derived composites are highlighted. [ABSTRACT FROM AUTHOR]