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Transparent conductive oxide (TCO) film acts as the window layer and carrier transport layer of silicon heterojunction (SHJ) solar cells. The optoelectrical and contact properties of TCO films, as well as the sputtering damage, limit the further efficiency improvement. Herein, the microstructure, morphology, and optoelectrical properties of sputtering‐prepared zinc‐doped indium oxide (IZO) are analyzed. The substrate temperature has a significant impact on the film growth and the cell performance. The IZO film is amorphous when substrate temperature is below 200 °C, while it seems the emergence of nanocrystals with the increased temperature, resulting in the highest conductivity (3070 S cm−1) and carrier mobility (47.9 cm2 V−1 s−1). In addition, the low carrier concentration and surface potential of IZO promote less optical parasitic absorption and higher work function. The IZO films are applied as the contact layer of SHJ solar cells. An impressive efficiency of 24.02% on an M2‐sized wafer is achieved, indicating great potential for the mass production application after careful optimization. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries are deemed as optimal energy devices for the next generation of high‐energy‐density energy storage. However, several problems such as low energy density and short cycle life hinder their application in industry. Here, MoS2–MoN heterostructure nanosheets grown on carbon nanotube arrays as free‐standing cathodes are reported. In this heterostructure, MoN works as a promoter to provide coupled electrons to accelerate the redox reaction of polysulfides while the MoS2, with a two‐dimensional layered structure, provides smooth Li+ diffusion pathways. Through their respective advantages, both MoN and MoS2 could mutually boost the process of "adsorption‐diffusion‐conversion" of polysulfides, which have a synergy enhancement effect to restrain the lithium polysulfides from shuttling. The designed cathodes show excellent long‐term cycling performances of 1000 cycles at 1C with a low decay rate of 0.039% per cycle and a high rate capability up to 6C. A high initial areal capacity of 13.3 mAh cm−2 is also achieved under a low electrolyte volume/sulfur loading (E/S) ratio of 6.3 mL g−1. This strategy of promoting polysulfide conversion by heterostructure MoS2–MoN as presented in this work can provide a more structured design strategy for future advanced Li–S energy storage systems. [ABSTRACT FROM AUTHOR]

Room-temperature sodium-ion batteries have attracted great attentions for large-scale energy storage applications in renewable energy. However, exploring suitable anode materials with high reversible capacity and cyclic stability is still a challenge. The VS4, with parallel quasi-1D chains structure of V4+(S22-)2, which provides large interchain distance of 5.83 Å and high capacity, has showed great potential for sodium storage. Here, the uniform cuboid-shaped VS4 nanoparticles are prepared as anode for sodium-ion batteries by the controllable of graphene oxide (GO)-template contents. It exhibits superb electrochemical performances of high-specific charge capacity (≈580 mAh·g-1 at 0.1 A·g-1), long-cycle-life (≈98% retain at 0.5 A·g-1 after 300 cycles), and high rates (up to 20 A·g-1). In addition, electrolytes are optimized to understand the sodium storage mechanism. It is thus demonstrated that the findings have great potentials for the applications in high-performance sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Si nanoparticle (Si-NP) composite anode with high rate and long cycle life is an attractive anode material for lithium-ion battery (LIB) in hybrid electric vehicle (HEV)/pure electric vehicle (PEV). In this work, a carbon nanotube (CNT)/reduced graphene oxide (rGO)/Si nanoparticle composite with alternated structure as Li-ion battery anode is prepared. In this structure, rGO completely wraps the entire Si/CNT networks by different layers and CNT networks provide fast electron transport pathways with reduced solid-state diffusion, so that the stable solid-electrolyte interphase layer can form on the whole surface of the matrix instead of on single Si nanoparticle, which ensure the high cycle stability to achieve the excellent cycle performance. As a result, the CNT/rGO/Si-NP anode exhibits high performances with long cycle life (≈455 mAh g−1 at 15 A g−1 after 2000 cycles), high specific charge capacity (≈2250 mAh g−1 at 0.2 A g−1, ≈650 mAh g−1 at 15 A g−1), and fast charge/discharge rates (up to 16 A g−1). This nanostructure anode with facile and low-cost synthesis method, as well as excellent electrochemical performances, makes it attractive for the long life cycles at high rate of the next generation LIB applications in HEV/PEV. [ABSTRACT FROM AUTHOR]

The inherent low ionic conductivity of PVDF‐based electrolytes at room temperature and lithium dendrite penetration hinder its further application. Herein, a LaF3 doped Poly(vinylidene fluoride‐chlorotrifluoroethylene) (P(VDF‐ctfe)) quasi‐solid electrolyte is developed. High‐flux channels are created due to the optimization of the lithium environment that lanthanum preferentially competes coordination with anionic species for relaxing lithium hopping. Lithium carriers are therefore highly free and unbound at the molecular level, resulting in a high ionic conductivity (σ) of 0.7 mS cm−1 and a transfer number (tLi+) of 0.79 at 25 °C. Moreover, the in situ organic–inorganic LiF‐rich dielectric layer effectively improves the stability and compatibility of the electrode/electrolyte interface, ensuring interfacial lithium conduction while facilitating stable Li+ plating/stripping. As a result, the optimized Li/ATCSE‐3%/Li can deliver favorable compatibility at 0.1 and 0.3 mA cm−2 for stable Li+ plating/stripping for 2000 and 1200 h, respectively. The high‐mass loading (6.4 mg cm−2) pouch cell delivers a stable cycling performance over 100 cycles with a capacity retention of 85.8% at 0.3 °C. This work is anticipated to provide considerable insight into the creative design of lithium transport of polymer‐based for practical quasi‐solid‐state lithium metal batteries. [ABSTRACT FROM AUTHOR]