Exsolution catalysts on perovskite oxides are useful in electrochemical energy conversion processes. Here, we report that the size and density of the exsolved metal nanoparticles can be manipulated by cotuning the temperature and voltage in operando, to improve the electrocatalytic activity of perovskite oxides. We show that the population density of the exsolved particles increases with shock voltage at a constant temperature. In addition, the size of the exsolved metal nanoparticles decreases and the number density increases upon voltage shock when the exsolution takes place at lower temperatures, due to higher nucleation rate and lower growth rate of nanoparticles. The perovskite oxide with the smaller size and higher density of exsolved catalysts shows the highest relative enhancement in electrocatalytic activity. For example, a factor of similar to 15x enhancement of the peak power density is achieved after voltage shock at a relatively low temperature of 700 degrees C. The ability to tune the particle size and population density as well as the electrocatalytic activity in operando improves the flexibility of the application of the exsolution-based materials in-but not limited to-fuel cells.

High-performance perovskite oxides are instrumental in catalytic processes and energy conversion. The exsolution of metallic nanoparticles from perovskite oxide hosts to form metal/oxide heterogeneous catalysts provides unprecedented opportunities for manipulating the catalytic activity of perovskites. Herein, we design and demonstrate a new approach to rapidly trigger exsolution and tune the electrochemical performance of perovskites. We show that by applying pulsed thermal shock several times (∼50 ms pulse width) and voltage shock for ∼40 s, exsolution-based products can be prepared on a timescale of seconds. With an increase in the number of pulses, the particle density increases first due to an increase in the concentration of oxygen vacancies that can serve as nucleation sites and then reaches a threshold governed primarily by the content of exsolvable metal atoms in the host lattice. Owing to the additionally generated active sites and conducting paths for active species, perovskite activity is significantly improved, thus eventually yielding a prominent enhancement in electrochemical performance.

Benefitted from the highly efficient and environmentally friendly characteristics, solid oxide fuel cell (SOFC) is a highly promising energy conversion device. For a SOFC, the eventual performance is greatly limited by the electrochemical activity of the cathode. Recently, multicomponent high-entropy perovskites have shown excellent performance as cathodes. However, there is still a gap in the exploration of their microscopic mechanism. This study systematically investigates the effects of configurational entropy and temperature on the structural evolution and oxygen ion transport performance of multi-component perovskites through molecular dynamics simulations. By changing the atomic ratio of A-site elements and the concentration of oxygen vacancies, three different high-entropy perovskite models are constructed. The structural characteristics are analyzed through density distribution, stress changes, and radial distribution functions, while the thermodynamic and kinetic properties are evaluated using methods such as mean square displacement, diffusion coefficient, ionic conductivity, vibrational density of states, and vibrational entropy. Results show that an increase in configurational entropy can bring about enhanced density fluctuations and more obvious local structural disorder, which is conducive to oxygen ion migration. The increase in temperature and configurational entropy significantly promotes oxygen ion diffusion, resulting in higher ionic conductivity. Moreover, the increase in temperature strengthens low-frequency vibration modes, which support the enhanced diffusion of oxygen ions. This study provides theoretical guidance for designing high-entropy perovskite materials with high performance for SOFCs.

High-temperature proton exchange membranes (HT-PEMs) are crucial to widen the working temperature window of proton exchange membrane fuel cells (PEMFCs). In this study, we propose doping clays, including kaolin, bentonite, and sepiolite, into polybenzimidazole (PBI) to regulate phosphoric acid (PA) uptake and retention. We report that the interaction between PA and surface -OH groups of the clays governs both PA uptake and electrochemical performance. Kaolin, with its rigid lamellar structure and abundant Si-OH/Al-OH groups, forms hydrogen bonding and interfacial coordination with PA, enabling uniform distribution and effective confinement of acid molecules. Consequently, the PA-kaolin/PBI composite PEM exhibits superior electrical and electrochemical properties. 145% enhancement of peak power density is achieved as compared to that of the pristine one at 200 degrees C. Concurrently, the PA retention improves similar to 23%. This work paves a new way to tune the thermal and electrochemical performance of HT-PEMFCs.

Arsenic emissions from coal combustion pose significant environmental, and their effective removal under oxygen-rich flue gas conditions remains difficult. In this study, density functional theory calculations were employed to systematically investigate the adsorption behavior of As2O3 on Fe2O3 (001) surfaces doped with eight different transition metals. In addition to analyzing the direct adsorption of arsenic, the influence of pre-adsorbed oxygen on the arsenic capture process was also understood from the perspectives of thermodynamics and kinetics. The findings show that the adsorption of As2O3 is stronger than O2 on all doped surfaces, indicating a thermodynamic preference for arsenic adsorption. The linear correlation indicates that certain surfaces can simultaneously be beneficial for both the thermodynamic and kinetic aspects of the direct and indirect adsorption of As2O3. Among the dopants, Cr, Mn, and Co notably improve both the thermodynamic stability and kinetic feasibility of As2O3 adsorption. In particular, Cr doping causes significant electronic structure changes, which promote O2 activation and dissociation and enhance AsO interactions. This research offers theoretical guidance for designing efficient adsorbents for arsenic removal .

Perovskite-type heterogeneous catalysts are useful in diverse fields especially for the gas-solid catalysis system. However, because of the intrinsically low catalytic activity of the perovskite catalyst, the system's catalytic efficiency is usually low. In this study, we propose to rapidly switch the activity of the perovskite catalyst by plasma treatment. We report that by hydrogen plasma treatment for ∼13 min, a large number of nanoparticles with a small size appear on the surface of the La0.33Ca0.46Ce0.01Ti0.94Ni0.06O3-δ (LCCTN) perovskite, resulting in a significant enhancement of activity. Moreover, it is demonstrated that the exsolved nanoparticles can be successfully dissolved after oxygen plasma treatment for ∼18 min, primarily attributed to the strong driving force provided to the system. By alternative treatments of hydrogen and oxygen plasma, the LCCTN activity can be well switched. When applying LCCTN as a symmetrical solid-oxide fuel cell's electrode, the performance is prominently improved via switching the catalytic activity. At 900 °C, a peak power density of 1.1 W cm-2 is acquired for the plasma-switched LCCTN, which is more than 7 times higher than that of the pristine one. Also, the cell shows good reversibility. This work explores a way to switch the perovskite catalyst's activity and polarity in a rapid manner.

Electrical energy and chemical energy play an important role in developing the emerging intelligent vehicle and artificial intelligence. Essentially, in well‐designed energy devices, they can be converted with each other and stored based on electrochemical reactions. Since the eventual performance relates closely with the physiochemical properties of the electrode catalysts, it is crucial to tune their microstructure to enhance the reaction kinetics and performance of energy devices. Benefitted from its superb spatial distribution of exsolved nanoparticles and uniquely anchored architecture, exsolution is a robust technique to improve performance for energy conversion and storage. Here, we review the characteristics and mechanisms of exsolution to provide solid knowledge on rationally designing and fabricating of novel exsolution‐derived energy products with excellent properties. Moreover, to trigger inspirations to create new types of energy devices and widen the application window, the recent advances in the exsolution application in energy areas covering fuel cells, electrolysers and batteries, and the fundamental principles of the exsolution effect on tuning their performance are comprehensively reviewed and analyzed. Lastly, the potential directions to further improve the energy devices' performance are discussed.

The chemical looping process for hydrogen production is garnering increased attention due to its capability to directly generate high-purity hydrogen (H-2) with minimal energy expenditure. Within the chemical looping hydrogen generation (CLHG) framework, achieving high H-2 yields and fuel conversion rates is crucial for enhancing energy efficiency, thus propelling the innovation of oxygen carriers (OCs). In this study, we decorated Fe2O3-Al2O3 by incorporating minor amounts of copper oxide (CuO) and nickel oxide (NiO) and assessed its efficacy in the biomass gasification gas-fueled CLHG process. Comprehensive characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), hydrogen/methane temperature-programmed reduction (H-2/CH4-TPR), and steam temperature-programmed oxidation (H2O-TPO), were employed to elucidate the underlying reaction mechanisms. Our findings reveal that Fe2O3-Al2O3, with the co-addition of CuO and NiO (4.55 wt%), outperforms both unmodified Fe2O3-Al2O3 and those with single metal oxide additions in the CLHG process. Notably, the fuel conversion, H-2 yield, steam conversion, and H-2 energy efficiency were markedly improved, achieving peak values of >99%, 6.35 mmol per g Fe2O3, >70%, and 77.9%, respectively. XPS and XRD analyses indicate a robust interaction among Fe2O3, CuO, and NiO, leading to the formation of a spinel ferrite phase during OC calcination. Additionally, H-2/CH4-TPR and H2O-TPO analyses confirm the enhanced redox reactivity of Fe2O3-Al2O3 with the co-addition of CuO and NiO. Time-resolved studies on OC conversion and phase evolution during the reduction process highlight the synergistic effects of CuO and NiO in boosting the OC reduction rate. The formation of FeNi and Cu in the early stage of the OC reduction process reduces oxygen vacancy formation energy, further promoting the deep reduction of the OC.

Solid oxide fuel cell (SOFC) is a useful electrochemical device that can directly convert chemical energy into electrical energy. Benefitted from their mixed ionic and electronic conducting property and good stability in a wide oxygen partial pressure (pO2) window, perovskite oxides are widely applied in SOFCs. However, due to the intrinsically low electrochemical activity, perovskite-based cells usually show inferior output at low temperatures. Herein, it is proposed to engineer both the surface and the bulk of perovskite to improve its electrocatalytic performance. First, it is demonstrated that by progressive extreme processing (extreme plasma ≈5 min + extreme voltage shock ≈50 s), the activity of perovskite anode La0.35Ca0.45Ti0.84Fe0.08Ni0.08O3- δ (LCTFN) can be significantly enhanced, primarily attributed to the increased concentration of oxygen vacancy and the improved conductivity after engineering the surface and the bulk of LCTFN, and thus bringing about an enhanced kinetics of hydrogen oxidation reaction. At a relatively low temperature of 700 °C, a favorable peak power density of 1.2 W cm-2 is obtained for the bulk-engineered LCTFN, which is ≈24 times higher than that of the pristine LCTFN. This study establishes a new method to effectively activate the perovskite oxide in a rapid manner and lower the working temperature of perovskite anode-based SOFCs.

Solid-state lithium-ion batteries are widely accepted as the promising next-generation energy storage technology due to higher energy density and improved safety compared to conventional lithium-ion batteries with liquid electrolytes. Large-area solid-state electrolyte (SSE) films with adequate thickness control, improved ionic conductivity, and good interfacial contact can reduce internal resistance, increase the real energy density of batteries, and reduce manufacturing costs. Optimization of SSE properties at the particle scale and large-scale preparation of SSE films are key to the development of high-performance solid-state lithium-ion batteries and their industrialization. Therefore, this paper provides a comprehensive review of SSE, covering both particle-level features like the effects of particle size, density, and air stability on the electrochemical performance, as well as four major routes for large-scale preparation and relevant strategies for structural optimization of SSE films. In addition, the effects of large-area SSE films on the electrochemical performance of solid-state batteries and their applications in pouch solid-state lithium-ion battery systems are discussed in detail. Finally, the design principles of SSE particles and SSE films are summarized and the development direction of thin SSEs is envisaged. In this paper, the effects of SSE on the electrochemical performance of batteries at the particle scale and optimization strategies, followed by four mainstream and other methods for large-area preparation of SSE films are introduced. The aim is to provide a comprehensive overview of SSE film design and to promote the development of solid-state batteries.image

>Symmetrical solid oxide cells （SSOCs） are very useful for energy generation and conversion. To fabricate the electrode of SSOC, it is very time-consuming to use the conventional approach. In this work, we design and develop a novel method, extreme heat treatment （EHT）, to rapidly fabricate electrodes for SSOC. We show that by using the EHT method, the electrode can be fabricated in seconds （the fastest method to date）, benefiting from enhanced reaction kinetics. The EHT-fabricated electrode presents a porous structure and good adhesion with the electrolyte. In contrast, tens of hours are needed to prepare the electrode by the conventional approach, and the prepared electrode exhibits a dense structure with a larger particle size due to the lengthy treatment. The EHT-fabricated electrode shows desirable electrochemical performance. Moreover, we show that the electrocatalytic activity of the perovskite electrode can be tuned by the vigorous approach of fast exsolution,deriving from the increased active sites for enhancing the electrochemical reactions. At 900℃, a promising peak power density of 966mWcm -2 is reached. Our work exploits a new territory to fabricate and develop advanced electrodes for SSOCs in a rapid and high-throughput manner.

Production of electrical energy in an environmental-friendly manner is important for meeting the increasing demand of electricity in smart vehicles and energy devices. Benefitted from its moderate working temperatures and high conversion efficiency, proton exchange membrane fuel cell (PEMFC) has received broad attention and commercialized rapidly in the past decades. Herein, we comprehensively review the advanced types of electrolytes and their underlying working mechanisms to offer a considerate guidance to develop novel electrolytes with high proton conductivity and wide working temperature window. Moreover, to rationally design cost-effective and robust electrodes, the well-developed anode and cathode and their fundamental working principles are elaborately reviewed and discussed. Furthermore, from the viewpoint of overall structure, fabricating approaches of functional components of PEMFC and their corresponding influencing factors are minutely reviewed and analyzed with the aim of tuning cell performance and preparing PEMFC in a high-throughput way. Lastly, we highlight the conclusions of this review and present the penitential developing directions.

Electrospun nanofibers (NFs) have shown excellent properties including high porosity, abundant active sites, controllable diameter, uniform and designable structure, high mechanical strength, and superior resistance to external destruction, which are ideal nanoreactors for in situ characterizations. Among various techniques, in situ transmission electron microscopy (TEM) has enabled operando observation at the atomic level due to its high temporal and spatial resolution combined with excellent sensitivity, which is of great importance for rational materials design and performance improvement. In this review, the basic knowledge of in situ TEM techniques and the advantages of electrospun nanoreactors for in situ TEM characterization are first introduced. The recent development in electrospun nanoreactors for studying the physical properties, structural evolution, phase transition, and formation mechanisms of materials using in situ TEM is then summarized. The electrochemical behaviors of carbon nanofibers (CNFs), metal/metal oxide NFs, and solid‐electrolyte interphase for different rechargeable batteries are highlighted. Finally, challenges faced by electrospun nanoreactors for in situ TEM characterization are discussed and potential solutions are proposed to advance this field. image

Potassium-ion batteries (PIBs) have attracted ever-increasing interest due to the abundant potassium resources and low cost, which are considered a sustainable energy storage technology. However, the graphite anodes employed in PIBs suffer from low capacity and sluggish reaction kinetics caused by the large radius of potassium ions. Herein, we report nitrogen-doped, defect-rich hollow carbon nanospheres with contact curved interfaces (CCIs) on carbon nanotubes (CNTs), namely CCI-CNS/CNT, to boost both electron transfer and potassium-ion adsorption. Density functional theory calculations validate that engineering CCIs significantly augments the electronic state near the Fermi level, thus promoting electron transfer. In addition, the CCIs exhibit a pronounced affinity for potassium ions, promoting their adsorption and subsequently benefiting potassium storage. As a result, the rationally designed CCI-CNS/CNT anode shows remarkable cyclic stability and rate capability. This work provides a strategy for enhancing the potassium storage performance of carbonaceous materials through CCI engineering, which can be further extended to other battery systems.

Exsolution-based nanoparticle-decorated materials can be rapidly fabricated in several minutes by plasma treatment.

The indiscriminate utilization of nondegradable polyethylene terephthalate (PET)‐based products has triggered serious environmental pollution that has to be resolved vigorously. A simple synthesis of N‐doped carbon nanotubes from recycled PET (NCNTs r‐PET ) was developed by a nitric acid‐assisted hydrothermal method. Experimental results and theoretical calculations show that the intrinsic defects in CNTs r‐PET would induce N‐doping by NH 3 generated from nitric acid during the hydrothermal process, thus producing the NCNTs r‐PET . The life cycle assessment proves that the developed method for N‐doped CNTs using r‐PET as the carbon source is more environmentally friendly than the conventional chemical vapor deposition using acetylene as the carbon source. As a typical application, the NCNTs r‐PET delivered an impressive sodium storage capacity with an ultralong lifespan. This work not only provides a new route to upcycling waste plastics into valuable carbonaceous materials in an ecofriendly manner, but also reveals a basic understanding of the N‐doping mechanism in carbonaceous materials.

Porous electrodes that conduct electrons, protons, and oxygen ions with dramatically expanded catalytic active sites can replace conventional electrodes with sluggish kinetics in protonic ceramic electrochemical cells. In this work, a strategy is utilized to promote triple conduction by facilitating proton conduction in praseodymium cobaltite perovskite through engineering non-equivalent B-site Ni/Co occupancy. Surface infrared spectroscopy is used to study the dehydration behavior, which proves the existence of protons in the perovskite lattice. The proton mobility and proton stability are investigated by hydrogen/deuterium (H/D) isotope exchange and temperature-programmed desorption. It is observed that the increased nickel replacement on the B-site has a positive impact on proton defect stability, catalytic activity, and electrochemical performance. This doping strategy is demonstrated to be a promising pathway to increase catalytic activity toward the oxygen reduction and water splitting reactions. The chosen PrNi0.7 Co0.3 O3- δ oxygen electrode demonstrates excellent full-cell performance with high electrolysis current density of -1.48 A cm-2 at 1.3 V and a peak fuel-cell power density of 0.95 W cm-2 at 600 °C and also enables lower-temperature operations down to 350 °C, and superior long-term durability.

目的 对比腹膜外与腹膜腔途径腹腔镜精索静脉高位结扎术治疗精索静脉曲张(VC)的临床疗效.方法 130例精索静脉曲张患者,按照就诊次序随机分为观察组(66例)和对照组(64例).观察组采用腹膜外途径腹腔镜精索静脉高位结扎术治疗,对照组采用腹膜腔途径腹腔镜精索静脉高位结扎术治疗.比较两组患者手术时间、排气时间、起床活动时间及住院时间,并发症发生情况及复发情况,手术前及术后6个月精液质量及精索静脉内径,分析术后情况.结果 两组手术时间比较,差异无统计学意义(P>0.05);观察组排气时间(5.1±2.4)h、起床活动时间(10.2±2.7)h及住院时间(2.1±1.3)d均短于对照组的(7.5±1.5)h、(12.2±2.2)h、(4.2±2.7)d,差异有统计学意义(P<0.05).两组阴囊水肿、急性附睾炎、 睾丸鞘膜积液发生率及复发率比较,差异无统计学意义(P>0.05).手术前及术后6个月,两组精子密度、活率、畸形率及精索静脉内径组间比较,差异无统计学意义(P>0.05);术后6个月,两组精子密度、活率、畸形率及精索静脉内径均优于手术前,差异有统计学意义(P<0.05).两组患者症状、体征全部缓解,无漏扎静脉;其中术前精液异常、婚后不育的31例患者术后6个月复查精液常规,精子密度、活率升高及畸形率下降,精液质量好转,1年后生育者12例.结论 腹膜外与腹膜腔途径腹腔镜精索静脉结扎术治疗精索静脉曲张疗效同样可靠有效,但腹膜外途径腹腔镜精索静脉高位结扎术有恢复快、腹腔干扰少等优势.

Ceramic fuel/electrolysis cells are key energy/material conversion devices. Here, we report that, by thermal shock, mixed ionic and electronic conducting electrode powders with a perovskite structure can be successfully synthesized within 2 min, while this procedure requires a two-step calcination and almost 40 h when a conventional furnace is used. This benefits from the high temperature supplied to the system, greatly enhancing the reaction kinetics among the raw materials. Moreover, typical electrolyte powders with a fluorite structure, such as (Y2O3)(0.08)(ZrO2)(0.92) (YSZ) and Sm0.2Ce0.8O1.95 (SDC), are also synthesized in several minutes through a thermal shock, which significantly reduces the fabrication time of a solid oxide cell. Also, one can easily prepare multiple samples at one time via tailoring the carbon support size. The availability of fast synthesis of the thermal-shock technique enables the development of new functional ceramic powders for solid-oxide cells in a high-throughput and economical manner.