The rapid development of electrochemical energy storage (EES) systems requires novel electrode materials with high performance. A typical 2D nanomaterial, layered transition metal dichalcogenides ...(TMDs) are regarded as promising materials used for EES systems due to their large specific surface areas and layer structures benefiting fast ion transport. The typical methods for the preparation of TMDs and TMD‐based nanohybrids are first summarized. Then, in order to improve the electrochemical performance of various kinds of rechargeable batteries, such as lithium‐ion batteries, lithium–sulfur batteries, sodium‐ion batteries, and other types of emerging batteries, the strategies for the design and fabrication of layered TMD‐based electrode materials are discussed. Furthermore, the applications of layered TMD‐based nanomaterials in supercapacitors, especially in untraditional supercapacitors, are presented. Finally, the existing challenges and promising future research directions in this field are proposed.
A typical 2D nanomaterial, layered transition metal dichalcogenides (TMDs) are emerging as promising materials for electrochemical energy storage systems. The typical methods for preparation of layered TMD‐based nanomaterials, as well as their applications in various kinds of rechargeable batteries and supercapacitors, are summarized. Moreover, current challenges and future research directions in this field are proposed.
The continuous exploration of clean‐energy technology is critical for the sustainable development of society. The recent work on the electric energy harvesting from water evaporation has made a ...significant contribution to the utilization of clean energy for self‐powering systems. Here, a novel metal–organic‐framework‐based hybrid nanomaterial is delicately designed and synthesized by the growth of UIO‐66 nanoparticles on 2D AlOOH nanoflakes. Due to the combined merits from the 2D morphology, which is inherited from the AlOOH nanoflakes, and the high surface potential, which originates from the UIO‐66 nanoparticles, the device made of the AlOOH/UIO‐66 hybrid nanomaterials can harvest electric energy from natural water evaporation. An open‐circuit voltage of 1.63 ± 0.10 V can be achieved on the prototype devices made of the hybrid nanomaterial. As a proof‐of‐concept application, a small electric appliance, e.g., a digital calculator, is powered up by a 3 × 3 device array connected in a combined series–parallel configuration.
A metal–organic framework (MOF)‐based hybrid nanomaterial is rationally designed and synthesized. Due to the 2D morphology and high surface potential, a prototype device made of MOF‐based hybrid nanomaterials can efficiently harvest the electric energy from water evaporation.
Transition‐metal dichalcogenides (TMDs) have attracted considerable attention in recent years because of their unique properties and promising applications in electrochemical energy storage and ...conversion. However, the limited number of active sites as well as blocked ion and mass transport severely impair their electrochemical performance. The construction of three‐dimensional (3D) architectures from TMD nanomaterials has been proven to be an effective strategy to solve the aforementioned problems as a result of their large specific surface areas and short ion and mass transport distances. This Review summarizes the commonly used routes to build 3D TMD architectures and highlights their applications in electrochemical energy storage and conversion, including batteries, supercapacitors, and electrocatalytic hydrogen evolution. The challenges and outlook in this research area are also discussed.
Electrochemistry in 3D: Three‐dimensional transition‐metal dichalcogenide architectures have shown great promise for electrochemical energy storage and conversion. This Review summarizes the commonly used strategies for the construction of such architectures, as well as their application in rechargeable batteries, supercapacitors, and electrocatalytic hydrogen evolution.
Since the discovery of graphene, diverse kinds of 2D nanomaterials have been explored and exhibited great promise for application in electrochemical energy storage and conversion. However, the ...restacking of 2D nanomaterials severely reduces their exposed active sites and thus impairs their electrochemical performance. Moreover, except for graphene, a large number of 2D nanomaterials normally possess unsatisfactory electrical conductivity. One of the effective strategies to address the aforementioned shortcomings is to hybridize 2D nanomaterials with 3D graphene architectures since large specific surface area and rapid transport pathways for electrons, ions, and mass can be achieved in the obtained hybrid materials. This review summarizes the typical strategies to hybridize 2D nanomaterials with 3D graphene architectures and then highlights the application of these hybrid materials in rechargeable batteries, supercapacitors, and electrocatalytic water splitting. The challenges and future research directions in this research area are also discussed.
The hybridization of 2D nanomaterials with 3D graphene architectures has offered a promising strategy to prepare high‐performance hybrid materials for electrochemical energy storage and conversion. This review summarizes the typical methods to hybridize 2D nanomaterials with 3D graphene architectures, as well as their application in rechargeable batteries, supercapacitors, and electrocatalytic water splitting.
Various kinds of amorphous materials, such as transition metal dichalcogenides, metal oxides, and metal phosphates, have demonstrated superior electrocatalytic performance compared with their ...crystalline counterparts. Compared to other materials for electrocatalysis, noble metals exhibit intrinsically high activity and excellent durability. However, it is still very challenging to prepare amorphous noble‐metal nanomaterials due to the strong interatomic metallic bonding. Herein, the discovery of a unique thiol molecule is reported, namely bismuthiol I, which can induce the transformation of Pd nanomaterials from face‐centered‐cubic (fcc) phase into amorphous phase without destroying their integrity. This ligand‐induced amorphization is realized by post‐synthetic ligand exchange under ambient conditions, and is applicable to fcc Pd nanomaterials with different capping ligands. Importantly, the obtained amorphous Pd nanoparticles exhibit remarkably enhanced activity and excellent stability toward electrocatalytic hydrogen evolution in acidic solution. This work provides a facile and effective method for preparing amorphous Pd nanomaterials, and demonstrates their promising electrocatalytic application.
A unique thiol molecule, namely bismuthiol I, is discovered, which can induce the amorphization of Pd nanomaterials by ligand exchange under ambient conditions. This method is applicable to different kinds of Pd nanomaterials without destroying their integrity. Notably, the obtained amorphous Pd nanoparticles show dramatically enhanced electrocatalytic activity and excellent durability toward the hydrogen evolution reaction.
Similar to heterostructures composed of different materials, possessing unique properties due to the synergistic effect between different components, the crystal‐phase heterostructures, one variety ...of hetero‐phase structures, composed of different crystal phases in monometallic nanomaterials are herein developed, in order to explore crystal‐phase‐based applications. As novel hetero‐phase structures, amorphous/crystalline heterostructures are highly desired, since they often exhibit unique properties, and hold promise in various applications, but these structures have rarely been studied in noble metals. Herein, via a one‐pot wet‐chemical method, a series of amorphous/crystalline hetero‐phase Pd nanosheets is synthesized with different crystallinities for the catalytic 4‐nitrostyrene hydrogenation. The chemoselectivity and activity can be fine‐tuned by controlling the crystallinity of the as‐synthesized Pd nanosheets. This work might pave the way to preparing various hetero‐phase nanostructures for promising applications.
Amorphous/crystalline heterophase Pd nanosheets exhibit crystallinity‐dependent chemoselectivity and catalytic activity.
A 3D porous Cu current collector is fabricated through chemical dealloying from a commerial Cu–Zn alloy tape. The interlinked porous framework naturally integrated can accommodate Li deposition, ...suppressing dendrite growth and alleviating the huge volume change during cycling. The Li metal anode combined with such a porous Cu collector demonstrates excellent performance and commerial potentials in Li‐based secondary batteries.
As the best electrocatalysts for alcohol oxidation reactions in direct alcohol fuel cells (DAFCs), Pt‐based nanomaterials still face the challenges of low utilization efficiency of Pt atoms and poor ...reaction kinetics. To address these issues, a self‐etching strategy is developed to prepare PtBi nanorings (NRs) with abundant low‐coordinated atoms and inhomogeneous tensile strain (≈4%). The obtained PtBi NRs exhibit superior activity toward methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR) in alkaline media. Particularly, the mass activities of PtBi NRs for MOR and EOR are 9.4 and 8.5 times higher than those of commercial Pt/C, respectively, which are among the best in the reported Pt‐based catalysts. The highly open structure of PtBi NRs is believed to provide plentiful catalytic active sites and increase the utilization of Pt atoms. Theoretical calculations show that the two important factors, i.e., adsorption energy with the key reaction intermediates and the energy barrier for the potential‐determining step, are significantly optimized owing to the synergy of tensile strain and the ligand effect in PtBi NRs. This study offers a promising strategy for the rational design and preparation of highly efficient catalysts for DAFCs.
PtBi nanorings with abundant low‐coordinated atoms and inhomogeneous tensile strain (≈4%) are prepared based on a self‐etching strategy. The obtained PtBi nanorings exhibit outstanding electrocatalytic activity and stability toward methanol oxidation reaction and ethanol oxidation reaction in alkaline media.
Developing a sustainable technology to produce hydrogen efficiently is crucial to realize the "hydrogen economy", which may address the growing energy crisis and environmental pollution nowadays. ...Electrocatalytic and photocatalytic hydrogen evolution reactions have received great attention during the past few decades since they can realize hydrogen production from the water splitting reaction directly. Although platinum has been widely used as a catalyst for the electrocatalytic and photocatalytic hydrogen evolution reaction (HER), its high cost and limited supply make it imperative to develop alternative high-performance catalysts. Ruthenium (Ru), the cheapest one among platinum-group metals, has been emerging as a promising candidate recently. Until now, tremendous efforts have been devoted to improving the HER performance of metallic Ru-based catalysts through the rational design and synthesis of Ru nanomaterials, in which the size, morphology, chemical composition and crystal phase could be controlled. In this review, we summarized the synthesis of various metallic Ru-based nanomaterials as catalysts for the HER, including pure Ru nanocrystals, Ru-based bimetallic nanomaterials and Ru/non-metal nanocomposites. Then, we covered the recent progress in the utilization of metallic Ru-based nanomaterials as catalysts for the electro- and photo-catalytic HER; meanwhile, the mechanisms and fundamental science behind morphology/composition/crystal structure-performance relationships were discussed in detail. Finally, the challenges and outlook are provided for guiding the development of metallic Ru-based electro- and photo-catalysts for further fundamental research and practical applications in renewable energy-related areas.
This review summarizes the recent progress on metallic Ru-based catalysts, including the preparation strategies, performance of electrocatalytic and photocatalytic hydrogen evolution.