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Aqueous zinc‐based energy storage devices have competitive advantages such as high power density, good safety, and wide source. However, because of the direct touch among zinc anode and aqueous electrolyte, dendrite growth and electrode side reactions are easy to occur in the plating and striping process, which seriously hinders the further development of aqueous zinc‐based energy storage devices. Therefore, it is urgent to solve the above problems to expand the existing energy storage devices. In this work, by adding an imidazo[1,2‐b]pyridazine (IP) electrolyte additive, the dendrites' growth and corrosion on the zinc anode surface could be effectively inhibited by the shielding‐anchoring double effects, which are verified by the comprehensive in situ and ex situ characterization techniques as well as the theoretical calculation support. Accordingly, the IP‐based electrolyte encourages extremely high stable zinc anode (cycling 2200 h at 1 mA cm−2) with high average Coulombic efficiency (98.72%). Moreover, the IP‐based Zn‐V2O5 full battery also exhibits excellent reversible capacity, reaching 160.8 mAh g−1 after 400 cycles at 2 A g−1. Through a straightforward alteration to the Zn anode surface, this study considerably enhances the use of highly stable and secure aqueous zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Designing efficient multifunctional electrocatalysts for water and urea splitting to produce green hydrogen presents a significant yet worthwhile challenge. Herein, the morphology and electronic structure of cobalt metaphosphate (Co2P4O12) by vanadium (V) doping, resulting in improved electrocatalytic activity and stability for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and urea oxidation reaction (UOR) are simultaneously regulated. Theory calculations show that V‐doped Co2P4O12 (V‐Co2P4O12) can boost the kinetics of catalytic reactions by optimizing the d‐band center of Co atoms and the binding strength of intermediates, as well as enhancing the density of states. Moreover, the doping of V into Co2P4O12 crystalline structure benefits the formation of a thicker amorphous layer during the catalytic process, which could enhance its alkaline corrosion resistance and stability. Additionally, the multilevel nanostructures of V‐Co2P4O12 provide rich active sites for catalytic reactions. As a result, a two‐electrode electrolyzer assembled by V‐doped Co2P4O12 delivers low voltages for overall water and urea splitting. The superior performance suggests that the proposed V‐doping strategy is a promising way to regulate electrocatalytic activity for catering to green electrocatalytic applications. [ABSTRACT FROM AUTHOR]

BiVO4 is one of the most promising photoanode materials for photoelectrochemical (PEC) solar energy conversion, but it still suffers from poor photocurrent density due to insufficient light‐harvesting efficiency (LHE), weak photogenerated charge separation efficiency (ΦSep), and low water oxidation efficiency (ΦOX). Herein, we tackle these challenges of the BiVO4 photoanodes using systematic engineering, including catalysis engineering, bandgap engineering, and morphology engineering. In particular, we deposit a NiCoOx layer onto the BiVO4 photoanode as the oxygen evolution catalyst to enhance the ΦOX of Fe‐g‐C3N4/BiVO4 for PEC water oxidation, and incorporate Fe‐doped graphite‐phase C3N4 (Fe‐g‐C3N4) into the BiVO4 photoanode to optimize the bandgap and surface areas to subsequently expand the light absorption range of the photoanode from 530 to 690 nm, increase the LHE and ΦSep, and further improve the oxygen evolution reaction activity of the NiCoOx catalytic layer. Consequently, the maximum photocurrent density of the as‐prepared NiCoOx/Fe‐g‐C3N4/BiVO4 is remarkably boosted from 4.6 to 7.4 mA cm−2. This work suggests that the proposed systematic engineering strategy is exceptionally promising for improving LHE, ΦSep, and ΦOX of BiVO4‐based photoanodes, which will substantially benefit the design, preparation, and large‐scale application of next‐generation high‐performance photoanodes. [ABSTRACT FROM AUTHOR]

Intelligent membranes with adaptive gating channels play a crucial role in cellular functions and separation processes. This study introduces a novel approach to controlling channel expansion using biomimetic adaptive aggregates, fundamentally overcoming the drawbacks of existing methods relying on intertwined polyelectrolyte chains for channel blockage. Specifically, a pH‐responsive 2D material membrane is constructed through the self‐assembling of protein‐mimetic zwitterionic polydopamine (ZPDA) soft molecular aggregates within graphene oxide (GO) interlayers. Similar to the conformational switch of inserted proteins in cellular membranes, the embedded ZPDA in GO nanofluidic channels undergoes an adaptive conformational transformation in response to pH changes. This dynamic adjustment of ZPDA physicochemical properties allows for reversible regulation of GO nanofluidic channel size and charge by external pH modulation. The resulting GO/ZPDA membrane exhibits programmable separation performance for dye molecules (i.e., water permeance of 18.8–35.4 L m−2 h−1 bar−1 and molecular selectivity of 73.7–32.9) and salt ions (i.e., ionic permeance of 0.69–1.25 mol m−2 h−1 and ionic selectivity of 20.8–21.9). This work sheds new light on the engineering of intelligent stimuli‐responsive 2D nanofluidic channels with adaptive gating properties, holding promise across a wide range of applications including separation, drug delivery, sensing, and catalysis. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium‐ion batteries (ASSLIBs) based on sulfide solid‐state electrolytes (S‐SSEs) are considered as one of the most promising choices to address the safety hazards of traditional lithium‐ion batteries. However, the high‐voltage cathodes, such as LiCoO2 (LCO) with high‐valence Co (+3), tend to spontaneously oxidize S‐SSEs, causing polarization increase and rapid degradation. Herein, a self‐sacrificing reductive interphase consisting of CoO/Li2CO3/C, is in situ constructed on LCO surface via a simple carbon‐induced thermal reduction of LCO. With such a design, the Co valence of LCO surface is reduced to +2, reducing the oxidative nature of LCO to avoid reactions with S‐SSEs. As a result, ASSLIBs using Li10GeP2S12 (LGPS) S‐SSEs achieve a high initial capacity of 144.9 mAh g‒1 at 0.2 C and retard 93.1% of initial capacity after 100 cycles. Additionally, excellent rate cyclability of 109.2 mAh g‒1 at 1.0 C with 81.5% retentive capacity for 200 cycles is attained as well. Comprehensive evidence strongly demonstrates the effectiveness of this self‐sacrificing reductive interphase in inhibiting the interfacial reactions and ensuring long‐term cyclability. The proposed concept of a self‐sacrificing reductive interface in this study paves the way for stabilizing the cathode/SSEs interface and offers a novel approach for the design of high‐performance sulfide‐based ASSLIBs. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT) and TiO2 nanofibre composite films are prepared and used as anode materials for lithium ion batteries (LIBs) without the use of binders and conventional copper current collector. The preliminary experimental results from X-ray diffraction, scanning electron microscopy and transmission electron microscopy suggest that the TiO2 nanofibres were well-dispersed and interwoven by the CNTs, forming freestanding, bendable and light weighted composite. In comparison with TiO2 nanofibre based LIBs, the CNTs could significantly improve the battery performance due to their high conductivity property and 3D network morphology. In both 1-3 V and 0.01-3 V testing voltage ranges, the as-prepared composites show excellent reversible capacity and capacity retention. The superior lithium storage capacity of the CNT/TiO2 composite was mainly attributed to dual functions of the CNTs - the CNTs not only provide conductive networks to assist the electron transfer but also facilitate lithium ion diffusion between the electrolyte and the TiO2 active materials by preventing agglomeration of TiO 2 nanofibres. This work demonstrates that the CNT-TiO2 composite film could be one type of potential electrode material for large-scale LIB applications. Crown Copyright © 2013 Published by Elsevier Ltd. All rights reserved.

Here we report a green production process polymer binder, Eastman AQ™ 55S (EAQ) polymer, which has plentiful active hydroxyl groups on its surface that is different from the chemically inert PVDF binder for lithium ion batteries (LIBs). The water soluble EAQ binder tuned the performance of the oxidized graphite with carboxyl group for the maximum effect. © 2013 The Royal Society of Chemistry.