EnergyChem最新文献

Organic-inorganic hybrid perovskite materials as a super star in the optoelectronics have showed great potential to lead a new photovoltaic technology revolution in the future. The main challenge blocking perovskite solar cells from industrialization is the instability issue, especially under heat, moisture, light or electric field conditions. The underlying mechanism for the current unsatisfactory stability performance is highly related to the defects in the solar cells. In particular, suppressing the defects evolvement in the perovskite absorbing layer is the key to maintain high power conversion efficiency (PCE) of solar cells due to the vulnerable and sensitive nature of perovskite materials. In this review, we analyzed the origins of defects in perovskite materials in the whole life cycle of perovskite devices and systematically discussed the effective strategies to eliminate or suppress the various intrinsic defects at three pivotal stages, namely, precursors, film fabrication and device operation. This review could potentially provide a new perspective for our peers to fabricate high-efficiency perovskite-based solar cells with stable performance, and further promoting the optimization and stabilization of perovskite related optoelectronics.

Redox polymers have the advantages of potentially low-cost, flexibility, sustainability, high redox activity, good electrochemical reversibility and high energy density, which have been widely reported in energy storage devices. Their electrochemical properties can be easily tailored by molecular engineering. Herein, the polymers including conducting polymers, organosulfur polymers, radical polymers, carbonyl polymers, polymers of arylamines, polymers based on unsaturated C-N and C-C bonds are overviewed and their applications in various metal-ion (Li⁺, Na⁺, K⁺, Zn²⁺, Mg²⁺, Ca²⁺, Al³⁺) batteries are comprehensively summarized. By virtue of the advantage of molecular design, conjugated porous polymers are specifically highlighted due to the further enhancement of ionic diffusion and accommodation of inserted ions, which combine the merits of flexibility of organic/polymeric materials and the advantages of porous structures. In the last section, strategies for improving electrochemical properties of metal-ion batteries are discussed, followed by the prospects of key challenges and future trends of redox polymers as electrode materials for advanced electrochemical energy storage devices.

Metal-organic frameworks (MOFs) / porous coordination polymers (PCPs) have emerged as a new family of conductive solid materials with outstanding performances in a wide variety of applications, including fuel cells, batteries, supercapacitors, catalysts, sensors, electronics, thermoelectrics, and spintronics. Only in past 10 years, novel strategies have been developed, which allowed for the rational design of both electronically and proton-conductive MOFs. In this review, the recent progress of MOF-based electronic and protic conductors, including materials preparations, conductivity measurements, conductive mechanisms, and applications is summarized and highlighted. Besides, the important breakthroughs of the MOF-based conductors for charge and proton transport, as well as the current status and challenges in this arena are elaborated.

Metal–organic frameworks (MOFs), an emerging class of porous materials, have shown intriguing and promising properties in a wide range of applications due to their versatile structures, large surface areas, tunable porosity and tailorable chemistry. In recent years one of the most active research fields is to explore energy applications of MOF-based materials. In this review, we present a critical overview on the recent progress of the use of MOF-based materials for gaseous fuel storage, chemical hydrogen storage, solar and electrochemical energy storage and conversion. The challenges and opportunities towards advanced energy technologies with the MOF-based materials are discussed.

Room-temperature nonaqueous rechargeable sodium ion batteries (SIBs) were first studied in 1980s, which had undergone rapid revival since 2010 and could be considered as the most promising candidate for alternative to lithium ion batteries (LIBs) because of their similar chemistry and the abundant sodium reserves. Extensive efforts have been devoted in the last decade to the development of advanced SIBs including cathodes, anodes, electrolytes, as well as electrode/electrolyte interphases. Nowadays the development of SIBs comes at a critical period. Considerable encouraging works have been reported, however, several challenges still hinder their practical applications. In this review, we summarize and discuss the current progress on electrode materials and electrolytes for SIBs. To push forward their practical applications, several promising materials as well as the electrolytes are highlighted. At the end of this review, the crucial challenges and perspectives for advanced nonaqueous SIBs are also proposed.

Proton exchange membrane fuel cells (PEMFCs) have attracted significant attention in the past three decades as a very promising power source for transportation applications. After tremendous efforts worldwide, fuel cell vehicles are now being pushed to the market. At the early stage of fuel cell vehicle pre-commercialization, however, the performance, cost, and durability of PEM fuel cells are still in the process of improvement. Understanding fundamentals of fuel cell electrocatalysis provides new insight into the choice and design of fuel cell materials and components with higher performance and durability. State of the art Pt based catalysts, carbon supports, proton conductive ionomers, and their structure effects are discussed in this review. The primary effort is made on the catalysts to increase oxygen reduction reaction (ORR) activity and durability by using low platinum-group metal (PGM) catalysts. The size effect and a variety of nanostructures (e.g., core-shell, Pt skin, dealloyed, monolayer, polyhedron facets, ligand, and strain effects) are comprehensively discussed to design and synthesize PGM catalysts for the cathode in PEMFCs. Using ionomer as the binder and proton conductors in the catalyst layer, the catalyst layer structure, ink preparation and deposition techniques, and ink drying process are also discussed. Due to the additional local transport resistance observed in fuel cell performance, the morphology and confinement effect of the ionomer thin film are also taken into account. In addition, the electrochemistry of the Pt/ionomer interface, as well as interfacial water and sulfonate poisoning are summarized.

Metal-organic frameworks (MOFs), also quoted as porous coordination polymers (PCPs), are causing great concern in supercapacitors (SCs) field owing to their ultra-high surface-areas, tailorable pore-sizes and shapes, and diverse structural architectures. This review mainly focuses on the recent progress in various branches of MOFs materials including porous coordination networks, two-dimensional (2D) MOFs, entangled MOFs, polyoxometalate MOFs (POMOFs), heterometallic MOFs, and some new emerging MOFs, as well as their applications in SCs. The superiority and the deficiency of various MOF types were systematically introduced and summarized. Additionally, the challenges and perspectives relate to pristine MOFs and MOFs-based composites for the applications in SCs have also been discussed. We hope that our review could provide guiding frameworks to design and fabricate MOFs materials with more practical energy-storage applications.

Due to the unsustainable fossil fuels, those conventional energy sources are diminishing and getting expensive. Since sun can provide insolation levels of 150–300 W/m², or 3.5–7.0 kWh/m² per day in most of the world's population live in areas, efficient utilization of the enormous energy source is continued to pursue. Solar energy can be usually harvested in a couple of different ways, among which harvesting solar energy by photon absorption in band gap materials and the subsequent collection of photo-induced charge carrier has been actively explored as promising strategy to store the abundant energy source. Halide perovskite materials, having optically high absorption characteristics and balanced charge transport properties, are considered a most potential light harvester to photovoltaics, as well as for solar energy conversion. Compared to charge transport, light harvesting capability is a must for high conversion efficiency of solar energy. In this review, we summarize the recent research progress in enhancing and modulating light harvesting capability of halide perovskite for PV devices and solar to fuel conversion from the perspectives of atomic level, crystal film level and device level, respectively.

Electrochemical CO₂ reduction reaction converts CO₂ into valuable chemical fuels, and has attracted quickly growing attention as a possible solution to mitigate the increasing atmospheric CO₂ concentration and close the broken carbon cycle. Its practical viability relies on the rational design and development of active, selective and durable electrocatalyst materials, preferably composed of earth abundant ingredients. Among different candidates, carbonaceous materials are of particular interest due to their earth abundance and low cost. In this review article, we overview the recent progress, current status and possible future research direction of carbonaceous materials for electrochemical CO₂ reduction. We start with fundamentals about electrochemical CO₂ reduction. They are then followed by detailed discussion about the research progresses of heteroatom (e.g., N, P, B and F) doped carbons and metal-nitrogen-carbon (e.g. Co-N-C and Fe-N-C) type materials. At last, a short perspective is offered to highlight possible future research directions. With this review, we hope to provide our readers a comprehensive picture of this quickly developing field.

In order to relieve current energy crisis and the related environment pollutions arising with fossil fuel, the development and application of sustainable and clean energy, such as solar and hydrogen, is anticipated as a prospective issue. It is urgent and significant to develop and construct various energy storage and conversion technologies and materials for the generation and utilization of clean energy sources. Polyoxometalates (POMs), a class of metal oxide polyanion clusters, can serve as outstanding candidates in energy-related fields like electrocatalysis, rechargeable battery, photocatalysis, and proton conduction, based on their plentiful redox property, semiconductor-like feature and acidity. Here, the selected recent and significant advances in the development of POM-based materials for sustainable and clean energy conversion and storage are reviewed and summarized, and special emphases are shown to the applications of POMs as platforms for hydrogen production, water oxidation, carbon dioxide reduction, Li-ion rechargeable batteries, supercapacitors, proton-exchange membrane fuel cells, dye-sensitized solar cells and so on. The results obtained from different catalytic/energy storage systems have been compared and we try to give a better understanding on catalytic reactivity-catalysts structure correlation as well as to put a picture for the rational design of electrochemical electrodes.