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Benefiting from the creation of new photovoltaic materials and innovations in device architectures, organic photovoltaic (OPV) cells are booming. Nonetheless, their prosperity is also accompanied by challenges, such as tedious synthetic routes, increasing costs and insufficient operational stability under practical stresses. Polythiophene, with a simple chemical structure, high scalability and excellent charge transport ability, is expected to be the most promising candidate among all kinds of polymer donors. Ternary mixing, as a simple and effective method for improving the efficiency and stability of OPVs, has attracted significant attention in recent decades. This review provides an overview of the recent advances in ternary OPVs based on polythiophene and discusses the role of various third components in three types of OPV active layers, where polythiophene serves as either the host material or additive, and also clarifies how the third component plays a role in determining morphology and device performance, and finally proposes future research directions for ternary OPVs featuring polythiophene. In short, this review provides insights into polythiophene-based multicomponent systems and helps readers better understand the relationships between morphology, efficiency and stability. LESS      Full article

Lithium (Li) metal batteries (LMBs) have emerged as the most prospective candidates for post-Li-ion batteries. However, the practical deployment of LMBs is frustrated by the notorious Li dendrite growth on hostless Li metal anodes. Herein, a protonated Li manganese (Mn) oxide with a high Mn³⁺/Mn⁴⁺ ratio is used as a Li adsorbent for constructing highly stable Li metal anodes. In addition to the Mn³⁺ sites with high Li affinity that afford an ultralow Li nucleation overpotential, the decrease in the average Mnⁿ⁺ oxidation state also induces a disordered adsorbent structure via the Jahn-Teller effect, resulting in improved Li transfer kinetics with a significantly reduced Li electroplating overpotential. Based on the mutually improved Li diffusion and adsorption kinetics, the Li adsorbent is used as a versatile host to enable dendrite-free and stable Li metal anodes in LMBs. Consequently, a modified Li||LiNi_0.8Mn_0.1Co_0.1O₂ (NMC811) coin cell with a high NMC811 loading of 4.3 mAh cm^-2 delivers a high Coulombic efficiency of 99.85% over 200 cycles and the modified Li||NMC811 pouch cell also achieves a remarkable improvement in electrochemical performance. This work demonstrates a novel approach for the preparation of highly efficient Li protection structures for safe LMBs with long lifespans. LESS      Full article

Although carbon-supported platinum (Pt/C) has been generally used as a catalyst for the oxygen reduction reaction (ORR) in fuel cells, its practical application is limited by the corrosion reaction of the carbon support. Therefore, it is essential to develop new self-supported catalysts for the ORR. Noble metal aerogels represent highly promising self-supported catalysts with large specific surface area and excellent electrocatalytic activity. Classic sol-gel processes for aerogel synthesis usually take days due to the slow gelation kinetics. Here, we report a straightforward strategy to synthesize platinum-copper (PtCu) aerogels by reducing the metal salt solution with an excess of sodium borohydride at room temperature. The PtCu aerogels are formed in a relatively short time of 1 h through a rapid nucleation mechanism. The obtained PtCu aerogels have a highly porous structure with an appreciable topological surface area of 33.0 m²/g and mainly exposed (111) facets, which are favorable for the ORR. Consequently, the PtCu aerogels exhibit excellent ORR activity with a mass activity of 369.4 mA/mg_Pt and a specific activity of 0.847 mA/cm², which are 2.6 and 3.3 times greater than those of Pt/C, respectively. The PtCu aerogels show remarkable ORR catalysis among all the noble metal aerogels that have been reported. The porous morphology and outstanding electrocatalytic activities of the PtCu aerogels illustrate their promising applications in fuel cells. LESS      Full article

Despite the low cost, safety and high theoretical capacity of metallic zinc, zinc anodes face chronic problems, including zinc dendrites, corrosion and side reactions in aqueous zinc-ion batteries (ZIBs). Herein, a nitrogen-doped carbon nanoparticle coating layer derived from discarded cigarette filters is constructed to suppress parasitic side reactions and zinc dendrite growth. The dense coating layer isolates water from the zinc anode, effectively inhibiting side reactions. Furthermore, the special micro-mesoporous structure and sufficient zincophilic groups guarantee uniform Zn stripping/plating. Consequently, durable cycle stability (2400 cycles at a current density of 1 mA cm^-2) with a stable polarization potential is achieved for symmetrical cells. The coating layer derived in this study therefore has the potential to improve the electrochemical performance of ZIBs. LESS      Full article

Commercial carbonate electrolytes with poor oxidation stability and high flammability limit the operating voltage of Li-ion batteries (LIBs) to ~4.3 V. As one of the most promising candidates for electrolyte solvents, sulfolane (SL) has received significant interest because of its wide electrochemical window, low flammability and high dielectric permittivity. Unfortunately, SL-based electrolytes with normal concentrations cannot achieve highly reversible Li⁺ intercalation/deintercalation in graphite anodes due to an ineffective solid electrolyte interface, thus undermining their potential application in LIBs. Here, a low-concentration SL-based electrolyte (LSLE) is developed for high-voltage graphite||LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) full cells. A highly reversible graphite anode can be achieved through the preferential decomposition of the dual-salt LiDFOB-LiBF₄ in the LSLE. The addition of fluorobenzene further restrains the decomposition of SL, endowing uniform, robust and inorganic-rich interphases on the electrode surfaces. As a result, the LSLE with improved thermal stability can support the MCMB||NCM811 full cells at 4.4 V, evidenced by an excellent cycling performance with capacity retentions of 83% after 500 cycles at 25 ℃ and 82% after 400 cycles at 60 ℃. We believe that the design of this fluorobenzene-containing LSLE offers an effective routine for next-generation low-cost and safe electrolytes for high-voltage LIBs. LESS      Full article

Semiconductor membrane fuel cells are a new promising R&D for solid oxide fuel cells and proton ceramic fuel cells. There is a challenge of the electronic short circuit issue by using semiconductor to replace conventional electrolyte membrane. In this work, type II band alignment of the semiconductor heterostructure based on Mg-doped ZnO and ZnO can, on one hand, block electrons passing through the junction, and on the other hand, trigger the ionic properties of membrane to boost the fuel cell performance. The Mg doping into ZnO creates more oxygen vacancies at the surface of ZnO, leading to enhanced ionic transport, and meaningful fuel cell performance of 673 mW/cm²; while the Mg-doped ZnO/ZnO heterostructure fuel cell has delivered 997 mW/cm² and OCV 1.04 V at 520 ^oC. It is worth highlighting that the constructed heterostructure interface, especially the band bending and constituted build-in electric field, plays a pivotal role in enhancing the ionic transport and suppressing the electron passing through the internal device. First principal calculations using density functional theory confirmed the doping of Mg and the formation of heterostructure with ZnO to help for enhancing charge carriers and separations. This work suggests that the constructed type II band alignment or the semiconductor heterostructure is useful for developing advanced fuel cells. LESS      Full article