查看更多>>摘要：Although metal halide perovskites are increasingly popular for the next generation of efficient photovoltaic devices,the inevitable defects from the preparation process have become the notorious barrier to further improvement of performance,which increases non-radiative recombination and lowers the power conversion efficiency of solar cells.Surface passivation strategies have been affirmed as one of the most practical approaches to suppress these defects.Therefore,it is necessary to have a detailed review on the surface passivation to reveal the improvements of the devices.Herein,the mechanism and recent advances of surface passivation have been systematically summarized with respect to various passivation approaches,including the Lewis acid-base,the low-dimensional perovskite,inorganic molecules,and polymers.Finally,the review also offers the research trend and prospects of surface passivation.
Dongwei MaDu YuanCarlos Ponce de LeónZheng Jiang...
25-42页
查看更多>>摘要：Aluminum-ion batteries(AIBs)with Al metal anode are attracting increasing research interest on account of their high safety,low cost,large volumetric energy density(≈8046 mA h cm-3),and environmental friendliness.Specifically,the reversible Al electrostripping/deposition is achieved with the rapid development of room temperature ionic liquids,and rapid progress has been made in fabricating high-performance and durable AIBs during the past decade.This review provides an integrated comprehension of the evolution of AIBs and highlights the development of various non-aqueous and aqueous electrolytes including high-temperature molten salts,room temperature ionic liquids,and gel-polymer electrolytes.The critical issues on the interplay of electrolytes are outlined in terms of the voltage window span,the effective ion species during charge storage(Al3+ or AlxCly-)and their underlying charge transfer(e.g.,interfacial transfer and diffusion),and the solid electrolyte interface formation and its role.Following the critical insight,future perspectives on how to practically design feasible AIBs are given.
查看更多>>摘要：The rapid progress of flexible electronics tremendously stimulates the urgent demands for the matching power supply systems.Flexible transparent electrochemical energy conversion and storage devices(FT-EECSDs),with endurable mechanical flexibility,outstanding optical transmittance,excellent electrochemical performance,and additional intelligent functions,are considered as preferable energy supplies for future self-powered flexible electronic systems.A comprehensive review of the reasonable design of flexible transparent electrode and recent progress on the FT-EECSDs is presented herein.The manufacturing techniques of generally classified three types of flexible transparent electrodes are systematically summarized.Emphasis is given to the recent developments in the transparent solid-state electrolyte,flexible transparent energy conversion,and storage devices.The standard evaluation methods and reasonable evaluation parameters to evaluate the flexibility and transparency of FT-EECSDs are highlighted.Additionally,the typical integrated applications of FT-EECSDs are also described.Finally,the current challenges and a future perspective on the research and development direction are further outlined.
查看更多>>摘要：Multivalent-ion(such as Zn2+,Mg2+,Al3+)batteries are considered as a prospective alternative for large-scale energy storage.However,the main problem of cathode materials for multivalent-ion batteries is the sluggish diffusion of multivalent ions.Many cathode materials will self-adjust under electrochemical conditions to achieve the optimal state for multivalent-ion storage.In this review,the significant role of electrochemical in situ structural reconstruction of cathode materials is suggested.The types,basic characteristics,and formation mechanisms of reconstructed phases have been systematically discussed and commented.The most important insight we pointed out is that the cathode materials with loose structures after in situ electrochemical activation are conducive to the reversible diffusion of multivalent ions.Moreover,several crucial issues of electrochemical activation and reconstruction were further analyzed and discussed.The challenges and future perspectives are presented in the final section.
查看更多>>摘要：Development and utilization of hydrogen energy is an effective way to achieve carbon neutrality,only hydrogen production through electrolytic water splitting meets the goal of zero carbon emission.To facilitate the large-scale commercialization of water splitting devices,the development of highly efficient and low-cost catalysts to reduce the energy consumption is essential.MoS2 has been regarded as a promising electrocatalyst to replace platinum in hydrogen evolution reaction due to its low price and unique 2D layered structure.However,the poor conductivity and inert basal planes of MoS2 limited its wide-spread application.Recently,researches have demonstrated that the conductivity and active sites of MoS2 can be improved by heteroatoms doping or constructing of heterogeneous structures.In this review,the recent progress of Mo-based catalysts are summarized centered on MoS2 based on interface engineering and anion engineering,including MoS2-MoO2,MoS2-Mo2C,MoS2-MoNx,MoS2-MoP,and MoS2-MoSe2.The preparation method,structure,and performance of the catalysts are introduced and the possible mechanism behind the improved catalytic activity are revealed to give readers an overall comprehension on the progress of the Mo-based electrocatalysts for hydrogen evolution reaction.In addition,an outlook on future opportunities and development directions of Mo-based catalysts are proposed to facilitate the development of Mo-based catalysts for hydrogen production.
查看更多>>摘要：Miniaturized sound generators are attractive to realize intriguing functions.Thermoacoustic device's application is seriously limited due to the frequency-doubling phenomenon.To address this issue,photoacoustic sound generator is considered as a promising alternative.Here,based on vertical single-wall carbon nanotubes(CNTs)array,we introduce a photoacoustic sound generator with internal nano-Helmholtz cavity.Different from traditional device that generates sound by periodically heating up the open space air around material,this sound generator produces an audio signal by forming a forced vibration of the air inside the CNTs.Interestingly,anomalous photoacoustic behavior is observed that the sound pressure level(SPL)curve has a resonance peak,the corresponding frequency of which is inversely proportional to the CNTs array's height.Furthermore,the energy conversion efficiency of this photoacoustic device is 1.64 times as large as that of a graphene sponge-based photoacoustic device.Most importantly,this device can be employed for music playing,bringing a new clew for the development of musical instruments in the future.
查看更多>>摘要：MIL-101(Cr)is a promising moisture absorbent for solar-driven water harvesting from moisture to tackle the worldwide water shortage issue.However,the MIL-101(Cr)powder suffers from a long ab/desorption cycle due to the crystal aggregation caused by its inherent powder properties.Here,we demonstrate a MIL-101(Cr)nanofibrous composite membrane with a nanofibrous matrix where MIL-101(Cr)is monodisperse in the 3D porous nanofibrous matrix through a simple spray-electrospinning strategy.The continuous porous nanofibrous matrix not only offers sufficient sites for MIL-101(Cr)loading but also provides rapid moisture transport channels,resulting in a super-rapid ab/desorption duration of 50 min(including an absorption process for 40 min and a desorption process for 10 min)and multicycle daily water production of 15.9 L kg-1 d-1.Besides,the MIL-101(Cr)nanofibrous composite membrane establishes a high solar absorption of 92.8％,and excellent photothermal conversion with the surface temperature of 70.7 ℃ under one-sun irradiation.In addition,the MIL-101(Cr)nanofibrous composite membrane shows excellent potential for practical application due to its flexibility,portability,and use stability.This work provides a new perspective of shortening MOF ab/desorption duration by introducing a porous nanofibrous matrix to improve the specific water production for the solar-driven ab/desorption water harvesting technique.
查看更多>>摘要：The"battery type"inorganic electrode has been demonstrated the highly efficient sodium ion intercalation capacity for capacitive deionization.In this work,the CoMn2O4(CMO)microspheres with porous core-shell structure are prepared via co-precipitation and followed by annealing.The effects of annealing temperatures on the morphology,pore structure,valence state,and electrochemical behavior of CMO are explored.As electrode for capacitive deionization,the salt removal capacity and current efficiency of optimized AC ‖ CMO device reaches up to 60.7 mg g-1 and 97.6％,respectively,and the capacity retention rate is 74.1％after 50 cycles.Remarkably,both the in-situ X-ray diffraction and ex-situ X-ray diffraction analysis features that the intercalation/de-intercalation of sodium ions are governed by(103)and(221)crystal planes of CMO.Accordingly,the density functional theory calculations realize that the adsorption energies of Na+onto(103)and(221)crystal planes are higher than that of any other crystal planes,manifesting the priorities in adsorption of sodium atoms.Furthermore,the X-ray photoelectron spectra of pristine and post-CMO electrode highlights that the reversible conversion of Mn3+/Mn4+couple is resulted from the intercalation/de-intercalation of Na+,while this is irreversible for Co3+/Co2+couple.Beyond that,the CMO electrode has been proven the selectivity removal of Na+over K+and Mg2+in a multi-cation stream.
查看更多>>摘要：Lithium-air battery has emerged as a viable electrochemical energy technology;yet a substantial overpotential is typically observed,due to the insulating nature of the discharge product Li2O2 that hinders the reaction kinetics and device performance.Furthermore,finite solid-solid/-liquid interfaces are formed between Li2O2 and catalysts and limit the activity of the electrocatalysts in battery reactions,leading to inadequate electrolytic efficiency.Herein,in-situ doping of Li2O2 by select metal ions is found to significantly enhance the lithium-air battery performance,and Co2+stands out as the most effective dopant among the series.This is ascribed to the unique catalytic activity of the resulting Co-Ox sites towards oxygen electrocatalysis,rendering the lithium-air battery self-catalytically active.Theoretical studies based on density functional theory calculations show that structural compression occurs upon Co2+doping,which lowers the energy barrier of Li2O2 decomposition.Results from this study highlight the significance of in situ electrochemical doping of the discharge product in enhancing the performance of lithium-air battery.
查看更多>>摘要：Two-dimensional materials with active sites are expected to replace platinum as large-scale hydrogen production catalysts.However,the rapid discovery of excellent two-dimensional hydrogen evolution reaction catalysts is seriously hindered due to the long experiment cycle and the huge cost of high-throughput calculations of adsorption energies.Considering that the traditional regression models cannot consider all the potential sites on the surface of catalysts,we use a deep learning method with crystal graph convolutional neural networks to accelerate the discovery of high-performance two-dimensional hydrogen evolution reaction catalysts from two-dimensional materials database,with the prediction accuracy as high as 95.2％.The proposed method considers all active sites,screens out 38 high performance catalysts from 6,531 two-dimensional materials,predicts their adsorption energies at different active sites,and determines the potential strongest adsorption sites.The prediction accuracy of the two-dimensional hydrogen evolution reaction catalysts screening strategy proposed in this work is at the density-functional-theory level,but the prediction speed is 10.19 years ahead of the high-throughput screening,demonstrating the capability of crystal graph convolutional neural networks-deep learning method for efficiently discovering high-performance new structures over a wide catalytic materials space.
万方数据
维普