Latest ArticlesHydrogen (H2) is considered to be a promising substitute for fossil fuels. Two-dimensional (2D) nanomaterials have exhibited an efficient electrocatalytic capacity to catalyze hydrogen evolution reaction (HER). Particularly, phase engineering of 2D nanomaterials is opening a novel research direction to endow 2D nanostructures with fascinating properties for deep applications in catalyzing HER. In this review, we briefly summarize the research progress and present the current challenges on phase engineering of 2D nanomaterials for their applications in electrocatalytic HER. Our summary will be of significance to provide fundamental understanding for designing novel 2D nanomaterials with unconventional phases to electrochemically catalyze HER.
Lithium–sulfur (Li-S) batteries are regarded as one of the most promising energy storage devices because of their low cost, high energy density, and environmental friendliness. However, Li-S batteries suffer from sluggish reaction kinetics and serious "shuttle effect" of lithium polysulfides (LiPSs), which causes rapid decay of battery capacity and prevent their practical application. To address these problems, introducing single-atom catalysts (SACs) is an effective method to improve the electrochemical performance of Li-S batteries, due to their high catalytic efficiency and definite active sites for LiPSs. In this paper, we summarized the latest developments in enhancing the electrochemical performance of cathode for Li-S batteries through introducing different SACs. Furthermore, we briefly introduced the catalytic mechanism of SACs and discussed the strategies of synthesizing SACs, including the spatial confinement strategy and the coordination design strategy. Finally, the challenges and prospects in this field are proposed. We believe that this review would help to design and fabricate high-performance Li-S batteries via introducing SACs and boost their practical application.
Fast-charging is considered to be a key factor in the successful expansion and use of electric vehicles. Current lithium-ion batteries (LIBs) exhibit high energy density, enabling them to be used in electric vehicles (EVs) over long distances, but they take too long to charge. In addition to modifying the electrode and battery structure, the composition of the electrolyte also affects the fast-charging capability of LIBs. This review provides a comprehensive and in-depth overview of the research progress, basic mechanism, scientific challenges and design strategies of the new fast-charging solution system, focusing on the influences that the compositions of liquid and solid electrolytes have on the fast-charging performance of LIBs. Finally, new insights, promising directions and potential solutions for the electrolytes of fast-charging systems are proposed to stimulate further research on revolutionary next-generation fast-charging LIB chemistry.
Sluggish kinetics of lithium/sulfur (Li/S) conversion chemistry and the ion channels formation in the cathode is still a bottleneck for developing future Li/S batteries with high-rate, long-cycling and high-energy. Here, a rational cathode structure design of an oxygen (O) and nitrogen (N) tailoring carbon fiber aerogel (OCNF) as a host material integrated with platinum (Pt) electrocatalysis interface is employed to regulate Li/S conversion chemistry and ion channel. The Pt nanoparticles were uniformly sprayed onto the S surface to construct the electrocatalysis interface (Pt/S/OCNF) for generating ion channels to promote the effective penetration of electrolyte into the cathode. This Pt/S/OCNF gives the cathode a high sulfur utilization of 77.5%, an excellent rate capacity of 813.2 mAh/g (2 C), and an outstanding long-cycling performance with a capacitance retention of 82.6% and a decay of 0.086% per cycle after 200 cycles at 0.5 C. Density functional theory (DFT) calculations reveal that the Pt electrocatalysis interface makes the cathode a high density of state (DOS) at Fermi level to facilitate the electrical conductivity, charge transfer kinetics and electrocatalysis to accelerate the lithium polysulfides (LiPSs) electrochemical conversion. Furthermore, the unique chemisorption structure and adsorption ability of Li2Sn (n = 1, 2, 4, 6, 8) and S8 on OCNF are attributed to the bridging effects of interfacial Pt and the bonding of N-Li. The Pt electrocatalysis interface combined with the unique 3D hierarchical porous structure and abundant functional active sites at OCNF guarantee strong adsorption confinement, fast Li/S electrocatalytic conversion and unblocked ion channels for electrolyte permeation in cathode.
Fabricating an efficient charge transfer pathway at the compact interface between two kinds of semiconductors is an important strategy for designing hydrogen production heterojunction photocatalysts. In this work, we prepared a compact, stable and oxygen vacancy-rich photocatalyst (SnO2/TiO2 heterostructure) via a simple and reasonable in-situ synthesis method. Briefly, SnCl2–2H2O is hydrolyzed on the TiO2 precursor. After the pyrolysis process, SnO2 nanoparticles (5 nm) were dispersed on the surface of ultrathin TiO2 nanosheets uniformly. Herein, the heterojunction system can offer abundant oxygen vacancies, which can act as active sites for catalytic reactions. Meanwhile, the interfacial contact of SnO2/TiO2 grading semiconductor oxide is uniform and tight, which can promote the separation and migration of photogenerated carriers. As shown in the experimental results, the hydrogen production rate of SnO2/TiO2 is 16.7 mmol h−1 g−1 (4.4 times higher than that of TiO2), which is owing to its good dynamical properties. This work demonstrates an efficient strategy of tight combining SnO2/TiO2 with abundant oxygen vacancies to improve catalytic efficiency.
Traditional methods of preparing metal-organic frameworks (MOFs) compounds have the disadvantages such as poor dispersion, inefficient and discontinuous process. In this work, microchannel reactor is used to prepare MOFs-derived zeolite-imidazole material via flash nanoprecipitation to form ZIF-67 + PEI(FNP), which reduces the MOF synthesis time down to millisecond time interval while keeping the synthesized ZIF-67 + PEI(FNP) highly dispersed. The Co@N–C(FNP)catalyst obtained by flash nanoprecipitation and carbonization has a higher Co content and thus more active sites for oxygen reduction reaction than the Co@N–C(DM) catalyst prepared by direct mixing method. Electrochemical tests show that the Co@N–C(FNP) catalyst prepared by this method has excellent oxygen reduction performance, good methanol resistance and high stability. The onset potential and half-wave potential of Co@N–C(FNP) are 0.92 VRHE and 0.83 VRHE, respectively, which are higher than that of Co@N–C(DM) (Eonset = 0.90 VRHE and E1/2 = 0.83 VRHE). Moreover, the Zn-air battery assembled with Co@N–C(FNP) as the cathode catalyst has high open circuit voltage, high power density and large specific capacity. The performance of these batteries has been comparable to that of Pt/C assembled batteries. Density functional theory (DFT) calculations confirm that the Co (220) crystal plane present in Co@N–C(FNP) have stronger adsorption energy than that of Co (111) crystal plane in Co@N–C(DM), leading to better electrocatalytic performance of the former.
A lithium-sulfur (Li-S) system is an important candidate for future lithium-ion system due to its low cost and high specific theoretical capacity (1675 mAh/g, 2600 Wh/kg), which is greatly hindered by the poor conductivity of sulfur, large volume change and dissolution of lithium polysulfides. Two-dimensional (2D) materials with monolayers or few-layers usually have peculiar structures and physical/chemical properties, which can resolve the critical issues in Li-S batteries. Especially, the metal-based 2D nanomaterials, including ferrum, cobalt or other metal-based composites with various anions, can provide high conductivity, large surface area and abundant reaction sites for restraining the diffusion for lithium polysulfides. In this mini-review, we will present an overview of recent developments on metal-based 2D nanomaterials with various anions as the electrode materials for Li-S batteries. Since the main bottleneck for the Li-S system is the shuttle of polysulfides, emphasis is placed on the structure and components, physical/chemical interaction and interaction mechanisms of the 2D materials. Finally, the challenges and prospects of metal-based 2D nanomaterials for Li-S batteries are discussed and proposed.
Efficient CO2 reduction reaction (CO2RR) is one of the important topics in energy and environment field, but improving the electrochemical selectivity of specific product is a great challenge. Herein, we reported a unprecedented two-dimensional (2D) metal−organic framework with CuO4 unit (denoted as Cu-HHTT, HHTT = 9, 10-dihydro-9, 10-[1,2]benzenoanthracene-2, 3, 6, 7, 14, 15-hexaol) as the electrocatalyst for CO2RR. Cu-HHTT exhibits high performance for CO2RR to produce CO, namely Faradaic efficiency of 96.6% toward CO with a current density of 18 mA/cm2 at the potential of −0.6 V vs. RHE. Density function theory reveals that the desorption of CO species exhibits a lower energy barrier than that of hydrogenation of *CO intermediate, resulting in CO as the main product instead of alcohols or hydrocarbons.
Nickel cobalt bimetallic heterogeneous sulfides are attractive battery-type materials for electrochemical energy storage. However, the precise synthesis of electrode materials that integrate highly efficient ions/electrons diffusion with abundant charge transfer channels has always been challenging. Herein, an effective and concise controllable hydrothermal approach is reported for tuning the crystalline and integrated structures of MOF-derived bimetallic sulfides to accelerate the charge transfer kinetics, and thus enabling rich Faradaic redox reaction. The as-obtained low-crystalline heterogeneous NiCo2S4/Co3S4 nanocages exhibit a high specific capacity (1023 C/g at 1 A/g), remarkable rate performance (560 C/g at 10 A/g), and outstanding cycling stability (89.6% retention after 5000 cycles). Furthermore, hybrid supercapacitors fabricated with NiCo2S4/Co3S4 and nitrogen-doped reduced graphene oxide display an outstanding energy density of 40.8 Wh/kg at a power density of 806.3 W/kg, with an excellent capacity retention of 88.3% after 10000 charge-discharge cycles.
Thanks to tunable physical and chemical properties, two-dimensional (2D) materials have received intensive interest, endowing their excellent electrocatalytic performances for applications in energy conversion. However, their catalytic activities are largely determined by poor adsorption energy and limited active edge sites. Herein, a one-step electrochemical exfoliation strategy was developed to fabricate 2D Ni-doped MoS2 nanosheets (Ni-EX-MoS2) with a lateral size of ~500 nm and thickness of ~3.5 nm. Profiting from high electrical conductivity and abundant exposing active sites, Ni-EX-MoS2 catalyst displayed an admirable performance for electrochemical hydrogen evolution reaction (HER) with a low overpotential of 145 mV at 10 mA/cm2 as well as a small Tafel slope of 89 mV/dec in alkaline media, which are superior to those of the most reported MoS2-based electrocatalysts. The formed Ni species with tuning electronic structure played a crucial role as primary active center of Ni-EX-MoS2, as well as the forming stable 1T/2H phase MoS2 interface demonstrated a synergistic effect on electrocatalytic HER performance. Further, Ni-EX-MoS2 was employed as a cathode electrode for alkaline Zn-H2O battery, which displayed a high power density of 3.3 mW/cm2 with excellent stability. This work will provide a simple and effective guideline for design of electrochemically exfoliated transition metal-doped MoS2 nanosheets to inspire their practical applications in energy catalytic and storage.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62662699(Operation and Technical Support)
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
