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This article reports a bipolar polymer cathode material bearing azo benzene and diamine moieties for affordable and sustainable sodium-ion batteries. 

Abstract High‐efficiency and low‐cost catalysts for oxygen evolution reaction (OER) are critical for electrochemical water splitting to generate hydrogen, which is a clean fuel for sustainable energy conversion and storage. Among the emerging OER catalysts, transition metal dichalcogenides have exhibited superior activity compared to commercial standards such as RuO₂, but inferior stability due to uncontrolled restructuring with OER. In this study, we create bimetallic sulfide catalysts by adapting the atomic ratio of Ni and Co in Co_xNi_1‐xS_yelectrocatalysts to investigate the intricate restructuring processes. Surface‐sensitive X‐ray photoelectron spectroscopy and bulk‐sensitive X‐ray absorption spectroscopy confirmed the favorable restructuring of transition metal sulfide material following OER processes. Our results indicate that a small amount of Ni substitution can reshape the Co local electronic structure, which regulates the restructuring process to optimize the balance between OER activity and stability. This work represents a significant advancement in the development of efficient and noble metal‐free OER electrocatalysts through a doping‐regulated restructuring approach. 

One step pore diffusion mechanism of lithium ion transport in the solid electrolyte interphase (SEI) layer with discrete inorganic components enables the fast lithium conduction without slow solid state diffusion process. 

Abstract Tuning the properties of a pair of entangled electron and hole in a light-induced exciton is a fundamentally intriguing inquiry for quantum science. Here, using semiconducting hybrid perovskite as an exploratory platform, we discover that Nd²⁺-doped CH₃NH₃PbI₃(MAPbI₃) perovskite exhibits a Kondo-like exciton-spin interaction under cryogenic and photoexcitation conditions. The feedback to such interaction between excitons in perovskite and the localized spins in Nd²⁺is observed as notably prolonged carrier lifetimes measured by time-resolved photoluminescence, ~10 times to that of pristine MAPbI₃without Nd²⁺dopant. From a mechanistic standpoint, such extended charge separation states are the consequence of the trap state enabled by the antiferromagnetic exchange interaction between the light-induced exciton and the localized 4 fspins of the Nd²⁺in the proximity. Importantly, this Kondo-like exciton-spin interaction can be modulated by either increasing Nd²⁺doping concentration that enhances the coupling between the exciton and Nd²⁺4 fspins as evidenced by elongated carrier lifetime, or by using an external magnetic field that can nullify the spin-dependent exchange interaction therein due to the unified orientations of Nd²⁺spin angular momentum, thereby leading to exciton recombination at the dynamics comparable to pristine MAPbI₃. 

Bipolar porous polymers bearing carbonyl and amine groups were designed and synthesized as cathode materials in Na-ion and K-ion batteries, demonstrating great promise for high-performance and sustainable batteries. 

Abstract Porous carbons are the active materials of choice for supercapacitor applications because of their power capability, long-term cycle stability, and wide operating temperatures. However, the development of carbon active materials with improved physicochemical and electrochemical properties is generally carried out via time-consuming and cost-ineffective experimental processes. In this regard, machine-learning technology provides a data-driven approach to examine previously reported research works to find the critical features for developing ideal carbon materials for supercapacitors. Here, we report the design of a machine-learning-derived activation strategy that uses sodium amide and cross-linked polymer precursors to synthesize highly porous carbons (i.e., with specific surface areas > 4000 m²/g). Tuning the pore size and oxygen content of the carbonaceous materials, we report a highly porous carbon-base electrode with 0.7 mg/cm²of electrode mass loading that exhibits a high specific capacitance of 610 F/g in 1 M H₂SO₄. This result approaches the specific capacitance of a porous carbon electrode predicted by the machine learning approach. We also investigate the charge storage mechanism and electrolyte transport properties via step potential electrochemical spectroscopy and quasielastic neutron scattering measurements. 

Abstract Realizing extreme fast charging (XFC) in lithium‐ion batteries for electric vehicles is still challenging due to the insufficient lithium‐ion transport kinetics, especially in the electrolyte. Herein, a novel high‐performance electrolyte (HPE) consisting of lithium bis(fluorosulfonyl)imide (LiFSI), lithium hexafluorophosphate (LiPF₆) and carbonates is proposed and tested in pilot‐scale, 2‐Ah pouch cells. Moreover, the origin of improved electrochemical performance is comprehensively studied via various characterizations, suggesting that the proposed HPE exhibits high ionic conductivity and excellent electrochemical stability at high charging rate of 6‐C. Therefore, the HPE‐based pouch cells deliver improved discharge specific capacity and excellent long‐term cyclability up to 1500 cycles under XFC conditions, which is superior to the conventional state‐of‐the‐art baseline electrolyte.