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The solid-state Li-ion battery (SSB) is regarded as one of the most promising next-generation batteries due to its intrinsic safety and high energy density. Unfortunately, its development is plagued by the poor interface compatibility between the electrode and solid-state electrolyte. Herein, flame-retardant trimethyl phosphate (TMP) solvent along with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt and fuoroethylene carbonate (FEC) additive is utilized as a smart wetting agent to improve the interface compatibility between the Li-metal anode and the Li1.5Al0.5Ge1.5(PO4)(3) (LAGP) solid electrolyte. By taking advantage of such wetting agent, highly stable anodic and cathodic interfaces with improved physical contact and chemical stability are realized. As a result, the solid-state Li/LAGP/Li symmetrical cell with such wetting agent exhibits superior cycling performance over 1000 h with small polarization voltages. When adding such wetting agent to the solid-state Li/LAGP/LiFePO4 battery, we achieved a favorable initial capacity of about 140 mAh g(-1) at 0.5 C and can retain 80% of its initial capacity even after 700 cycles. Additionally, the solid-state Li-air battery with such wetting agent also shows stable cycling performance over 100 h. The strategy demonstrated here will encourage more research works on developing functional and safe wetting agents for solid-state batteries.

Due to the low material cost, simple preparation process, and no pollution to the environment, dye-sensitized solar cells (DSSCs) have become one of the important power conversion devices. The counter electrode (CE, also called cathode), an important part of DSSCs, plays a critical role in the photovoltaic performance of DSSCs. Platinum (Pt) with high electrocatalytic activity is the most commonly used CE material in DSSCs, which suffers from the problems of high price and poor stability, highlighting the importance of developing novel low-cost, active, and stable Pt-free CEs. In this work, a series of A-site deficient (La0.8Sr0.2)1–xFeO3-δ (x = 0, 0.02, 0.05, 0.1) perovskite oxides are designed to serve as CEs in DSSCs. Through investigating the influence of the A-site deficiency on the power conversion efficiency (PCE), it is found that the introduction of an appropriate deficiency in perovskite oxides is beneficial for catalytic activity of triiodide (I3–) reduction reaction (IRR) of the CE, thus improving the photovoltaic performance of DSSCs. Consequently, the (La0.8Sr0.2)0.98FeO3−δ/multiwalled carbon nanotubes (MWCNTs) CE-based device exhibits the highest PCE of 8.22%, while the Pt-based device only yields a PCE of 7.21%. The significantly enhanced efficiency of DSSCs is mainly attributed to the synergistic effect between the high oxygen vacancy concentration and the appropriate amount of Fe4+ as well as reduced particle size, which enhances the charge transfer capability and the I3– diffusion capability simultaneously. Furthermore, the decent IRR durability of (La0.8Sr0.2)0.98FeO3−δ/MWCNTs composites confers the corresponding DSSCs an excellent long-term stability. This work provides a facile way to design active and durable Pt-free perovskite oxide-based CEs in DSSCs, which may lay the foundation for the commercialization of DSSC technology.

Solid oxide fuel cells (SOFCs) based on Ni-based cermet anodes suffer from severe sulfur poisoning when operated on H2S-containing fuels (

Proton-conducting fuel cells (PCFCs) with a perovskite-type proton-conducting electrolyte show many advantages over conventional oxygen-ion-conducting ceramic fuel cells. Both electrode catalytic a...

Solid oxide fuel cells (SOFCs) as one of the clean electrochemical energy conversion devices have acquired increasing attention recently due to the high efficiency, low emission, and excellent fuel...

Although lead-based inorganic–organic perovskite solar cells (PSCs) have delivered the highest power conversion efficiency (PCE) to date of 25.2%, the toxic nature of lead and poor stability are th...

The cycling performance of lithium-sulfur (Li-S) batteries, which is a major parameter determining the practical application of such an advanced high-energy-density battery system (1675 mA h g(-1)), is strongly affected by the properties of the cathodic sulfur hosts. As a desirable sulfur host, it should possess high surface area, good electronic conductivity, and superior physisorption and chemisorption to polysulfides. Here, by taking advantage of the magnesiothermic denitriding technology, the graphitic carbon nitride (GCN) with a tunable nitrogen content, surface area, and pore volume has been designed as a sulfur host for high-performance Li-S batteries. With a nitrogen content of similar to 6%, a surface area of 594 m(2) g(-1), and a pore volume of about 2 cm(3) g(-1), the GCN-based host can retain sulfur and allow its reversible convention within cathodic region, thereby delivering a high capacity of 852.2 mA h g(-1) at 0.5 C with a low capacity decay of 0.12% per cycle within 300 cycles. This work provides a feasible way to design nitrogen-doped carbon materials with tunable nitrogen content and enlightens the host material design for practical Li-S batteries.

Renewable and clean energy supplies are highly critical for the reduction of greenhouse emissions and environmental pollution to realize a sustainable society. Among various techniques for using sustainable energy sources, such as solar energy, photocatalysis plays a crucial role in solving global problems, such as the energy crisis and environmental pollution. Thus, the design and development of Earth-abundant, low-cost, high-performance photocatalysts for water splitting and wastewater treatment are critical. Among these photocatalysts, Ruddlesden–Popper (RP) perovskites have attracted increasing attention in photocatalysis as a result of their unique structural, electronic, and optical characteristics. In this review, the recent advances of RP perovskites in photocatalysis are presented. The review begins with an introduction of the unique features of RP perovskites that are suitable for photocatalysis, which is followed by a discussion of the use of typical RP-type perovskite oxides as photocatalysts by highlighting several useful design strategies. Finally, the conclusions of this review, along with current challenges and future directions for the design of RP perovskites for photocatalysis, are presented and discussed. This review aims to provide helpful guidance for the future development of RP-type perovskite oxides for photocatalysis-based water splitting and wastewater treatment.

Solid-state Li-ion batteries (SSBs) have been regarded as the most promising systems to power electronic devices and electric vehicles because of their high energy density and safety. As the key co...

Advanced symmetric solid oxide fuel cells (SOFCs) with a reducible electrode were proposed. Specifically, La2NiO4 + La0.9Sr0.1Ga0.8Mg0.2O3−δ (LSGM) [or Sm0.2Ce0.8O1.9 (SDC)] composite electrodes were successfully fabricated by an infiltration method and tested for power generation. X-ray diffraction (XRD) results demonstrated there was no noticeable phase reaction between infiltrated La2NiO4 and LSGM (or SDC) scaffold, and scanning electron microscopy (SEM) analysis indicated that the La2NiO4 phase formed as nanoparticles that decorated the surface of the scaffold. Different from conventional symmetric SOFCs, the electrode material La2NiO4 of current cells was reduced under an anode atmosphere to form metallic nickel as a high active catalyst for fuel oxidation. After the reduction, the electrode morphology and geometric integrity were maintained for the infiltrated electrode. For thick electrolyte-supported symmetric SOFCs with infiltrated La2NiO4 electrodes, an attractive maximum power density of ∼550 m...