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Abstract Lithium-ion batteries (LIBs) have solidified their position as primary energy storage solutions for applications ranging from portable electronics to electric vehicles. As power-intensive applications expand, achieving fast charging/discharging performance is increasingly critical for high-energy-density batteries. However, the increased thickness of electrodes in LIBs presents significant challenges for charge (Li⁺ and electron) transfer kinetics, as longer charge migration distances hinder fast charging and discharging performance. Enormous efforts have been made to summarize advancements in materials chemistry—optimizing ionic pathways and crystal structure—to enhance Li⁺ transfer within the bulk of electrode materials. Yet, materials design and modifications fall short of fully addressing Li⁺and electron transport limitations in thick electrodes. Despite the significance of potentially offering a solution to these constraints, the strategic engineering of electrode architecture has been rarely discussed. In this mini-review, we highlight recent innovations in electrode structural design for fast-charging applications, examining gradient architectures, low-tortuosity structures, and novel current collector designs. By exploring these advanced approaches and offering perspectives on future developments, we aim to promote further advancements toward achieving high-energy-density, fast-charging LIBs. 

Enhanced Zn anode kinetics and reversibility are achieved at a high ZUR by guiding Zn²⁺plating underlying the SnO_1.17interphase with a regulated (101) orientation, surpassing those achieved by inducing Zn(002) plating overlying the interphase. 

This work demonstrates the design protocols for high-energy-density solid-state Li–S batteries (SSLSBs). Also, it highlights the challenging issues for achieving practical SSLSBs towards the application in next-level electric transportation. 

Despite the outstanding achievements in multiple areas such as displays and energy, oxide electronics has been limited to single-polar (n-type) applications due to the facile generation of oxygen vacancies as native donors. On the contrary, the processing of p-type oxides is restrained due to the high formation energy of native acceptors. Furthermore, the oxygen 2p orbitals of the majority of oxide semiconductors are anisotropic and localized to the valence band maximum (VBM), resulting in a large effective mass of holes and hence low carrier mobility. Hybrid orbital electronic configurations with cation d10 (closed shell structure) and cation s2 (pseudo-closed structure) have been suggested initially in complex oxides (e.g., CuMO2 where M= Al, Ga, and In; and SrCu2O2) to delocalize the oxygen 2p orbitals from the VBM. However, these complex oxides require high temperatures to process and are difficult to engineer the electrical properties of carrier density and carrier mobility due to the correlated nature of multi-cation species. Several single-cation p-type oxides such as PbO, Bi2O3, and SnO have emerged as well, where the energy level of a unique s-orbital of cations is similar to oxygen 2p orbitals, forming strong hybrid structures. In addition, a simpler single-cation structure leads to easier control of electrical properties required in practical device applications such as thin film transistors (TFT) and complementary logic inverters. We previously reported scalable processing of p-type SnOx through thermodynamic-based interfacial reactions as well as reactive sputtering.¹More recently, we also suggested multi-modal encapsulation to enhance TFT on- and off-state behaviors and identified a defect complex as an effective p-type doping agent.²However, challenges remain since the TFT off-state current is large, and the defect/trap state density is high. In this presentation, we share our approaches to engineer the off-state current and passivate the defect/trap states. In addition to channel thickness optimization, intrinsic (Sn vacancy or oxygen interstitial) and extrinsic (H-related species) doping strategies to adjust channel carrier density will be compared. The performance of several surface treatments (oxygen plasma and UV) and TFT back channel encapsulations (SiO2 and Al2O3) will be systematically compared. Then, the device performance of optimized p-type SnO TFTs and complementary inverters with n-type InZnO TFTs will be discussed. ReferencesLee et al., ACS Applied Materials & Interfaces, 13 (46), 55676–55686 (2021)Lee et al., ACS Applied Materials & Interfaces, 14 (48), 53999–54011 (2022) Acknowledgments This work was partially supported by National Science Foundation, Award number ECCS-1931088 and CBET-2207302. 

Electronic and optoelectronic devices often require multifunctional properties combined with conductivity that are not achieved from a single species of molecules. The capability to tune chain length, shape, and physicochemical characteristics of conductive copolymers provides substantial benefits for a wide range of scientific areas that require unique and engineered optical, electrical, or optoelectronic properties. Although efforts have been made to develop synthetic routes to realize such promising copolymers, an understanding of the process–structure–property relationship of the synthesis methods needs to be further enhanced. In addition, since traditional methods are often limited to achieving pinhole-free, large-area coverage, and conformal coating of copolymer films with thickness controllability, unconventional synthetic strategies to address these issues need to be established. This Perspective article intends to enhance knowledge on the process–structure–property relationship of functional copolymers by providing the definition of copolymers, polymerization mechanisms, and a comparison of traditional and emerging synthetic methods with reaction parameters and tuned physical properties. In parallel, practical applications featuring the desired copolymers in electronic, optical, and sensing devices are showcased. Last, a pathway toward further advancement of unique copolymers for next-generation device applications is discussed. 

Finite element analysis provides visual insights into conductive path evolution in a SiO₂-based memristor. Electrochemical impedance spectroscopy experimentally validated the theoretical findings by interpreting with an equivalent circuit. 

Abstract We report on the enhancement of electrical properties of unsubstituted polythiophene (PT) through oxidative chemical vapor deposition (oCVD) and mild plasma treatment. The work function of p-type oCVD PT increases after the treatment, indicating the Fermi level shift toward the valence band edge and an increase in carrier density. In addition, regardless of initial values, nearly the same work function is obtained for all the plasma-treated oCVD PT films as high as ∼5.25 eV, suggesting the pseudo-equilibrium state is reached in the oCVD PT from the plasma treatment. This increase in carrier density after plasma treatment is attributed to the activation of initially not-activated dopant species (i.e. neutrally charged Br), which is analogous to the release of trapped charge carriers to the valence band of the oCVD PT. The enhancement of electrical properties of oCVD PT is directly related to the improvement of the thin film transistor performance such as drain current on/off ratio, ∼10³and field effect mobility, 2.25 × 10⁻²cm²Vs⁻¹, compared to untreated counterparts of 10²and 0.09 × 10⁻²cm Vs⁻¹, respectively.