Energy & Environmental Materials最新文献

A heteronuclear dual transition metal atom catalyst is a promising strategy to solve and relieve the increasing energy and environment crisis. However, the role of each atom still does not efficiently differentiate due to the high activity but low detectability of each transition metal in the synergistic catalytic process when considering the influence of heteronuclear induced atomic difference for each transition metal atom, thus seriously hindering intrinsic mechanism finding. Herein, we proposed coordinate environment vary induced heterogenization of homonuclear dual-transition metal, which inherits the advantage of heteronuclear transition metal atom catalyst but also controls the variable of the two atoms to explore the underlying mechanism. Based on this proposal, employing density functional theory study and machine learning, 23 kinds of homonuclear transition metals are doping in four asymmetric C₃N for heterogenization to evaluate the underlying catalytic mechanism. Our results demonstrate that five catalysts exhibit excellent catalytic performance with a low limiting potential of −0.28 to −0.48 V. In the meantime, a new mechanism, “capture–charge distribution–recapture–charge redistribution”, is developed for both side-on and end-on configuration. More importantly, the pronate site of the first hydrogenation is identified based on this mechanism. Our work not only initially makes a deep understanding of the transition dual metal-based heteronuclear catalyst indirectly but also broadens the development of complicated homonuclear dual-atom catalysts in the future.

A comprehensive understanding of the dynamic processes at the catalyst/electrolyte interfaces is crucial for the development of advanced electrocatalysts for the oxygen evolution reaction (OER). However, the chemical processes related to surface corrosion and catalyst degradation have not been well understood so far. In this study, we employ LiCoO₂ as a model catalyst and observe distinct OER activities and surface stabilities in different alkaline solutions. Operando X-ray diffraction (XRD) and online mass spectroscopy (OMS) measurements prove the selective intercalation of alkali cations into the layered structure of LiCoO₂ during OER. It is proposed that the dynamic cation intercalations facilitate the chemical oxidation process between highly oxidative Co species and adsorbed water molecules, triggering the so-called electrochemical-chemical reaction mechanism (EC-mechanism). The results of this study emphasize the influence of cations on OER and provide insights into new strategies for achieving both high activity and stability in high-performance OER catalysts.

The search for safer next-generation lithium-ion batteries (LIBs) has driven significant research on non-toxic, non-flammable solid electrolytes. However, their electrochemical performance often falls short. This work presents a simple, one-step photopolymerization process for synthesizing biphasic liquid–solid ionogel electrolytes using acrylic acid monomer and P_111i4FSI ionic liquid. We investigated the impact of lithium salt concentration and temperature on ion diffusion, particularly lithium-ion (Li⁺) mobility, within these ionogels. Pulsed-field gradient nuclear magnetic resonance (PFG-NMR) revealed enhanced Li⁺ diffusion in the acrylic acid (AA)-based ionogels compared to their non-confined ionic liquid counterparts. Remarkably, Li⁺ diffusion remained favorable in the ionogels regardless of salt concentration. These AA-based ionogels demonstrate very good ionic conductivity (>1 mS cm⁻¹ at room temperature) and a wide electrochemical window (up to 5.3 V vs Li⁺/Li⁰). These findings suggest significant promise for AA-based ionogels as polymer solid electrolytes in future solid-state battery applications.

Water often presents significant challenges in catalysts by deactivating active sites, poisoning the reaction, and even degrading composite structure. These challenges are amplified when the water participates as a reactant and is fed as a liquid phase, such as trickle bed-type reactors in a hydrogen-water isotope exchange (HIE) reaction. The key balance in such multiphase reactions is the precise control of catalyst design to repel bulk liquid water while diffusing water vapor. Herein, a platinum-incorporated metal-organic framework (MIL-101) based bifunctional hydrophobic catalyst functionalized with long alkyl chains (C₁₂, dodecylamine) and further manufactured with poly(vinylidene fluoride), Pt@MIL-101-12/PVDF, has been developed which can show dramatically improved catalytic activity under multi-phase reactions involving hydrogen gas and liquid water. Pt@MIL-101-12/PVDF demonstrates enhanced macroscopic water-blocking properties, with a notable reduction of over 65% in water adsorption capacity and newly introduced liquid water repellency, while exhibiting a negligible increase in mass transfer resistance, i.e., bifunctional hydrophobicity. Excellent catalytic activity, evaluated via HIE reaction, and its durability underscore the impact of bifunctional hydrophobicity. In situ DRIFTS analysis elucidates water adsorption/desorption dynamics within the catalyst composite, highlighting reinforced water diffusion at the microscopic level, affirming the catalyst's bifunctionality in different length scales. With demonstrated radiation resistance, Pt@MIL-101-12/PVDF emerges as a promising candidate for isotope exchange reactions.

This study introduces a cut-to-fit methodology for customizing bulk aramid aerogels into form factors suitable for wearable energy storage. Owing to strong intercomponent bonds within aramid-based building blocks, it is possible to delaminate layered bulk aerogel into flexible and thinner sheets, enabling efficient mass production. This process allows for precise customization of aerogel dimensions, shape, and elasticity, ensuring high resilience to deformation along with excellent thermal and impact resistance. Incorporation of conductive carbon nanotubes on the surface significantly enhances electrical conductivity and multi-catalytic activity while retaining the inherent advantages of aramids. These advancements facilitate the use of flexible and conductive electrodes as air cathodes in solid-state zinc–air batteries (ZABs), which demonstrate superior cyclic performance and lifecycles exceeding 160 h. Furthermore, aramid-based packaging provides superior protection for pouch-type ZABs, ensuring a consistent power supply even in severe conditions. These batteries are capable of withstanding structural deformations and absorbing physical and thermal shocks, such as impacts and exposure to fire. Moreover, the innovative reassembly of custom-cut single-pouch cells into battery modules allows for enhanced power output, tailored to wearable applications. This highlights the potential of the technology for a wide array of wearable devices requiring dependable energy sources in demanding environments.

This study first demonstrates the potential of organic photoabsorbing blends in overcoming a critical limitation of metal oxide photoanodes in tandem modules: insufficient photogenerated current. Various organic blends, including PTB7-Th:FOIC, PTB7-Th:O6T-4F, PM6:Y6, and PM6:FM, were systematically tested. When coupled with electron transport layer (ETL) contacts, these blends exhibit exceptional charge separation and extraction, with PM6:Y6 achieving saturation photocurrents up to 16.8 mA cm⁻² at 1.23 V_RHE (oxygen evolution thermodynamic potential). For the first time, a tandem structure utilizing organic photoanodes has been computationally designed and fabricated and the implementation of a double PM6:Y6 photoanode/photovoltaic structure resulted in photogenerated currents exceeding 7 mA cm⁻² at 0 V_RHE (hydrogen evolution thermodynamic potential) and anodic current onset potentials as low as −0.5 V_RHE. The herein-presented organic-based approach paves the way for further exploration of different blend combinations to target specific oxidative reactions by selecting precise donor/acceptor candidates among the multiple existing ones.

Arising from the increasing demand for electric vehicles (EVs), Ni-rich LiNi_xCo_yMn_zO₂ (NCM, x + y + z = 1, x ≥ 0.8) cathode with greatly increased energy density are being researched and commercialized for lithium-ion batteries (LIBs). However, parasitic crack formation during the discharge–charge cycling process remains as a major degradation mechanism. Cracking leads to increase in the specific surface area, loss of electrical contact between the primary particles, and facilitates liquid electrolyte infiltration into the cathode active material, accelerating capacity fading and decrease in lifetime. In contrast, Ni-rich NCM when used as a single crystal exhibits superior cycling performances due to its rigid mechanical property that resists cracking during long charge–discharge process even under harsh conditions. In this paper, we present comparative investigation between single crystal Ni-rich LiNi_0.92Co_0.04Mn_0.04O₂ (SC) and polycrystalline Ni-rich LiNi_0.92Co_0.04Mn_0.04O₂ (PC). The relatively improved cycling performances of SC are attributed to smaller anisotropic volume change, higher reversibility of phase transition, and resistance to crack formation. The superior properties of SC are demonstrated by in situ characterization and battery tests. Consequently, it is inferred from the results obtained that optimization of preparation conditions can be regarded as a key approach to obtain well crystallized and superior electrochemical performances.

Homogeneous films with tailored microporous structures are crucial for several applications; however, fabricating such films presents significant challenges. This is primarily because most microporous materials have crystal sizes in the nano- and micrometer ranges, which inevitably generates intergranular spaces in the films, thereby complicating the fabrication of these thin films. In this study, functionalized metal–organic polyhedra (MOPs) are used as discrete microporous units and assembled into homogenous microporous films. The generation of intergranular spaces is avoided while controlling packing parameters and film thicknesses. Initially, the MOP units, influenced by van der Waals forces between carbon chains of functionalized adipic acids, display an affinity to form spindle-shaped blocks and islands. As the MOP concentration increases, these structures self-assembled into a hexagonally packed structure with an in-plane orientation and a maximum stacking of two layers of MOPs. By contrast, un-functionalized MOPs form a disordered film structure owing to random agglomeration. Evidently, functionalized adipic acid influences the orientation of the MOP network films with uniformly distributed micropores, effectively preventing the formation of intergranular spaces. Additionally, formaldehyde adsorption and desorption experiments revealed that the MOP network films possess superior adsorption and desorption capacities. The proposed approach signifies a breakthrough in the fabrication of homogenous microporous films.

The conversion of sound vibration into electrical potential is a critical function performed by cochlear hair cells. Unlike the regenerative capacity found in various other cells throughout the body, cochlear sensory cells lack the ability to regenerate once damaged. Furthermore, a decline in the quantity of these cells results in a deterioration of auditory function. Piezoelectric materials can generate electric charge in response to sound wave vibration, making them theoretically suitable for replacing hair cell function. This study explores an innovative approach using piezoelectric nanocomposite filaments, namely poly(vinylidene fluoride), poly(vinylidene fluoride)/barium titanate, and poly(vinylidene fluoride)/reduced graphene oxide, as self-powered acoustic sensors designed to function in place of cochlear hair cells. These flexible filaments demonstrate a unique ability to generate electricity in response to frequency sounds from 50 up to 1000 Hz at moderate sound pressure levels (60–95 dB), approaching the audible range with an overall acoustoelectric energy conversion efficiency of 3.25%. Serving as self-powered acoustic sensors, these flexible filaments hold promise for potential applications in cochlear implants, with a high sensitivity of 117.5 mV (Pa·cm²)⁻¹. The cytocompatibility of these filaments was assessed through in vitro viability tests conducted on three cell lines, serving as a model for inner ear cells.

In recent years, perovskite light-emitting diodes have witnessed a remarkable evolution in both efficiency and luminance levels. Nonetheless, the production of such devices typically relies on protracted synthesis procedures at elevated temperatures and vacuum/inert conditions (e.g. hot-injection synthesis), thus rendering them technically unsuitable for extensive display and/or lighting applications manufacturing. Although alternative synthetic protocols have been proposed, e.g. ligand-assisted reprecipitation, ultrasonic and microwave-based methods, their suitability for the construction of high-performing light-emitting diodes has been reported in only a few studies. In this study, we demonstrate the fabrication of highly efficient lighting devices based on CsPbBr₃ colloidal perovskite nanocrystals synthesized by a fast, energetically efficient, and up-scalable microwave-assisted method. These nanocrystals exhibit an impressive photoluminescence quantum yield of 66.8% after purification, with a very narrow PL spectrum centered at 514 nm with a full width at half-maximum of 20 nm. Similarly, the PeLEDs achieve a maximum external quantum efficiency of 23.4%, a maximum current efficiency of 71.6 Cd A⁻¹, and a maximum luminance level that exceeds 4.7 × 10⁴ Cd m⁻². Additionally, a significantly lower energy consumption for microwave-mediated synthesis compared with hot injection is demonstrated. These findings suggest that this synthetic procedure emerges as an outstanding and promising method towards a scalable and sustainable fabrication of high-quality perovskite light-emitting diodes.