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Zinc (Zn) metal batteries could be the technology of choice for sustainable battery chemistries owing to its better safety and cost advantage. However, their cycle life and Coulombic efficiency (CE) are strongly limited by the dendritic growth and side reactions of Zn anodes. Herein, we proposed an in situ construction of a metal-phosphonate-organic network (MPON) with three-dimensional interconnected networks on Zn metal, which can act as an ion enrichment layer for Zn anodes in Zn-metal batteries. This MPON with abundant porous structure and phosphate sites possesses ion enriching properties and high Zn 2+ transference number (0.83), which is beneficial for enhancing Zn 2+ migration and self-concentrating kinetics. Meanwhile, MPON offers hydrophobicity to effectively inhibit the water-induced Zn anode corrosion. As a result, the Zn electrode exhibits superior Zn/Zn 2+ reversibility of over 4 months at 3 mA cm -2 and a high CE of 99.6 %. Moreover, the Zn/NaV 3 O 8  ⋅ 1.5H 2 O and Zn/MnO 2 full cells using ultrathin Zn anodes (10 μm) exhibit high-capacity retention of 81 % and 78 % after 1400 and 1000 cycles, respectively. This work provides a unique promise to design high-performance anode for practical Zn-metal-based batteries., (© 2024 Wiley-VCH GmbH.)

The synthesis of hydrogen peroxide through artificial photosynthesis is a green and promising technology with advantages in sustainability, economy and safety. However, superoxide radical (⋅O 2 - ), an important intermediate in photocatalytic oxygen reduction to H 2 O 2 production, has strong oxidizing properties that potentially destabilize the catalyst. Therefore, avoiding the accumulation of ⋅O 2 - for its rapid conversion to H 2 O 2 is of paramount significance in improving catalyst stability and H 2 O 2 yield. In this work, a strategy was developed to utilize protonated groups for the rapid depletion of converted ⋅O 2 - , thereby the efficiency of photocatalytic synthesis of H 2 O 2 from CN was successfully enhanced by 47-fold. The experimental findings demonstrated that polydopamine not only improved carrier separation efficiency, and more importantly, provided the adsorption reduction active site for ⋅O 2 - for efficient H 2 O 2 production. This work offers a versatile approach for synthesizing efficient and stable photocatalysts., (© 2024 Wiley‐VCH GmbH.)

Numerous reported bioinspired osmotic energy conversion systems employing cation-/anion-selective membranes and solutions with different salinity are actually far from the biological counterpart. The iso-osmotic power generator with the specific ionic permselective channels (e.g., K + or Na + channels) which just allow specific ions to get across and iso-osmotic solutions still remain challenges. Inspired by nature, we report a bioinspired K + -channel by employing a K + selective ligand, 1,1,1-tris{[(2'-benzylaminoformyl)phenoxy]methyl}ethane (BMP) and graphene oxide membrane. Specifically, the K + and Na + selectivity of the prepared system could reach up to ≈17.8, and the molecular dynamics simulation revealed that the excellent permselectivity of K + mainly stemmed from the formed suitable channel size. Thus, we assembled the K + -selective iso-osmotic power generator (KSIPG) with the power density up to ≈15.1 mW/m 2 between equal concentration solutions, which is higher than traditional charge-selective osmotic power generator (CSOPG). The proposed strategy has well shown the realizable approach to construct single-ion selective channels-based highly efficient iso-osmotic energy conversion systems and would surely inspire new applications in other fields, including self-powered systems and medical materials, etc., (© 2023 Wiley-VCH GmbH.)

Nanofluidic reverse electrodialysis provides an attractive way to harvest osmotic energy. However, most attention was paid to monotonous membrane structure optimization to promote selective ion transport, while the role of external fields and relevant mechanisms are rarely explored. Here, we demonstrate a Kevlar-toughened tungsten disulfide (WS 2 ) composite membrane with bioinspired serosa-mimetic structures as an efficient osmotic energy generator coupling light. As a result, the output power could be up to 16.43 W m -2 under irradiation, outperforming traditional two-dimensional (2D) membranes. Both the experiment and simulation uncover that the generated photothermal and photoelectronic effects could synergistically promote the confined ion transport process. In addition, this membrane also possesses great anti-fouling properties, endowing its practical application. This work paves new avenues for sustainable power generation by coupling solar energy., (© 2023 Wiley-VCH GmbH.)

Biological proton channels play important roles in the delicate metabolism process, and have led to great interest in mimicking selective proton transport. Herein, we designed a bioinspired proton transport membrane by incorporating flexible 14-crown-4 (14C4) units into rigid frameworks of polyimine films by an interfacial Schiff base reaction. The Young's modulus of the membrane reaches about 8.2 GPa. The 14C4 units could grab water, thereby forming hydrogen bond-water networks and acting as jumping sites to lower the energy barrier of proton transport. The molecular chains present a vertical orientation to the membrane, and the ions travel between the quasi-planar molecular sheets. Furthermore, the 14C4 moieties could bond alkali ions through host-guest interactions. Thus, the ion conductance follows H + ≫K + >Na + >Li + , and an ultrahigh selectivity of H + /Li + (ca. 215) is obtained. This study provides an effective avenue for developing ion-selective membranes by embedding macrocycle motifs with inherent cavities., (© 2023 Wiley-VCH GmbH.)

Biological ion channels existing in organisms are critical for many biological processes. Inspired by biological ion channels, the heterogeneous electrospinning nanofiber membranes (HENM) with functional ion channels are constructed by electrospinning technology. The HENM successfully realizes ion-gating effects, which can be used for tunable energy conversions. Introduction of pyridine and carboxylic acid groups into the HENM plays an important role in generating unique and stable ion transport behaviors, in which gates become alternative states of open and close, responding to symmetric/asymmetric pH stimulations. Then we used the HENM to convert osmotic energy into electric energy which reach a maximum value up to 12.34 W m -2 and the output power density of HENM-based system could be regulated by ion-gating effects. The properties of the HENM provide widespread potentials in application of smart nanofluidic devices, energy conversion, and water treatment., (© 2022 Wiley-VCH GmbH.)

Improving the stability of cuprous oxide (Cu 2 O) is imperative to its practical applications in artificial photosynthesis. In this work, Cu 2 O nanowires are encapsulated by metal-organic frameworks (MOFs) of Cu 3 (BTC) 2 (BTC=1,3,5-benzene tricarboxylate) using a surfactant-free method. Such MOFs not only suppress the water vapor-induced corrosion of Cu 2 O but also facilitate charge separation and CO 2 uptake, thus resulting in a nanocomposite representing 1.9 times improved activity and stability for selective photocatalytic CO 2 reduction into CH 4 under mild reaction conditions. Furthermore, direct transfer of photogenerated electrons from the conduction band of Cu 2 O to the LUMO level of non-excited Cu 3 (BTC) 2 has been evidenced by time-resolved photoluminescence. This work proposes an effective strategy for CO 2 conversion by a synergy of charge separation and CO 2 adsorption, leading to the enhanced photocatalytic reaction when MOFs are integrated with metal oxide photocatalyst., (© 2020 Wiley-VCH GmbH.)

Osmotic energy, obtained through different concentrations of salt solutions, is recognized as a form of a sustainable energy source. In the past years, membranes derived from asymmetric aromatic compounds have attracted attention because of their low cost and high performance in osmotic energy conversion. The membrane formation process, charging state, functional groups, membrane thickness, and the ion-exchange capacity of the membrane could affect the power generation performance. Among asymmetric membranes, a bipolar membrane could largely promote the ion transport. Here, two polymers with the same poly(ether sulfone) main chain but opposite charges were synthesized to prepare bipolar membranes by a nonsolvent-induced phase separation (NIPS) and spin-coating (SC) method. The maximum power density of the bipolar membrane reaches about 6.2 W m -2 under a 50-fold salinity gradient, and this result can serve as a reference for the design of bipolar membranes for osmotic energy conversion systems., (© 2020 Wiley-VCH GmbH.)

In nature, biological machines and motors can selectively transport cargoes across the lipid membranes to efficiently perform various physiological functions via ion channels or ion pumps. It is interesting and challengeable to develop artificial motors and machines of nanodimensions to controllably regulate mass transport in compartmentalized systems. In this work, we show a system of artificial molecular motors that uses light energy to perform transmembrane molecule transport through synthetical nanochannels. After functionalizing the polymer nanochannels with azobenzene derivatives, these nanomachines exhibit autonomous selective transport behavior over a long distance upon simultaneous irradiation with UV (365 nm) and visible (430 nm) light. With new strategies or suitable materials for directed molecular movement, such device can be regarded as a precursor of artificial light-driven molecular pumps., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The controllable molecule transport is crucial to realize many highly valuable applications both in vivo and in vitro. Nanoporous membranes, with nanoscopic pores, high porosity, uniform pore dimensions, and controllable surface chemical properties, hold tremendous potential to achieve this function. Herein, we report a nano-gating system for on-demand molecule transport based on a peptide-gated nanoporous membrane. Acting as gatekeeper, the peptides introduced to the nanoporous membrane provide an opportunity to realize on-demand on-off states via reversible conformational switching of the peptides. This nano-gating system offers sustained release and can be used as a sophisticated molecule transport platform for localized drug delivery with a feedback function., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A tunable ionic diode is presented that is based on biomimetic structure-tailorable nanochannels, with precise ion-transport characteristics from ohmic behavior to bidirectional rectification as well as gating properties. The forward/reverse directions of the ionic diode and the degree of rectification can be well-regulated by combining the patterned surface charge and the sophisticated structure. This system creates an ideal platform for precise transportation of ions and molecules, and potential applications in analytical sciences are anticipated., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Light-controlled nanochannels are fabricated through self-assembling azobenzene-incorporated DNA (Azo-DNA) strands to regulate ion transport. By switching between collapsed and relaxed states using visible and ultraviolet light alternately, the Azo-DNA channels can be opened and closed because the conformation of Azo-DNA changes, that is, Azo-DNA is used as switchable controlling unit. In addition to sharing short response time and reversibility with other photoresponsive apparatuses, the Azo-DNA-based nanochannel system has advantages in good biocompatibility and versatile design, which could potentially be applied in light-controlled drug release, optical information storage, and logic networks., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A smart nanofluidic diode that exhibits both ion gating and ion current rectification has been developed using a 1-(4-amino-phenyl)-2,2,2-trifluoro-ethanone-functionalized, conical nanochannel in a polyimide (PI) membrane. The switch-like property can be tuned by controlling the wettability and charge distribution with carbonate ions. Such a nanodevice is advantageous for precisely controlling conductive states with an ultrahigh gating ratio of up to 5000, and a high rectification ratio of 27. By virtue of the high selectivity and sensitivity for carbonate ions, this nanofluidic diode may find applications in carbonate or carbon dioxide detection., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)