Advanced Functional Materials

Zhao, Jiarui; Wang, Zhen; Wang, Hao; Liu, Panbo; Che, Renchao

doi: 10.1002/adfm.202418282pmid: N/A

Special multilayer heterostructures and lattice modulation play a crucial role in the field of microwave absorption. Herein, a unique “nested doll” MoS2/V2O3 heterostructures are synthesized via crystal epitaxy growth and solvothermal strategy. The synchronized modulation of lattice spacing and interfacial vacancies in MoS2 nanosheets is achieved by adjusting the S2⁻ concentration. A high concentration of S2⁻ expands the MoS2 lattice spacing and increases interfacial vacancies, facilitating the precise modulation of the orderly arrangement of MoS2‐V2O3‐MoS2 layers and inducing interfacial polarization. By increasing the number of V2O3‐MoS2 layers from two to five, a built‐in electric field is formed, which enhances charge transfer from the MoS2 surface to the V2O3 core. The introduction of vacancies reduces the MoS2 band gap, lowers the electron hopping barrier, increases dielectric loss, and ultimately synergistically improves microwave absorption (MA). As a result, the “nested doll” MoS2/V2O3‐5 (5 layers) microspheres exhibit superior MA behavior compared to other MoS2/V2O3 absorbers. The reflection loss reaches −69.65 dB and the effective absorption bandwidth achieves 7.68 GHz. These discoveries have contributed to the further development of multilayer heterostructures and improved advances in the theory of energy band structures and electromagnetic properties.

Liu, Xiaoru; Zhao, Zhihao; Zhang, Baofeng; Hu, Yuexiao; Qiao, Wenyan; Gao, Yikui; Wang, Jing; Guo, Ziting; Zhou, Linglin; Wang, Zhong Lin; Wang, Jie

doi: 10.1002/adfm.202416944pmid: N/A

Triboelectric nanogenerator (TENG) offers a novel approach for converting high‐entropy mechanical energy into electrical energy, yet achieving high charge density remains critical. Optimizations using dielectrics with high specific capacitance have mitigated air breakdown, but charge loss within dielectrics persists as a limiting factor. Here, based on poly(vinylidene fluoride–trifluoroethylene–chlorofluoroethylene) (P(VDF‐TrFE‐CFE)) with high specific capacitance, (P(VDF‐TrFE‐CFE)) composites’ trap density and energy are engineered using high‐polarity interfaces from barium titanate (BTO) nanoparticles and dense chain segment stacking induced by electrostatic interaction with polyetherimide (PEI) to enhance charge retention capability. With modified high interfacial traps, an ultrahigh charge density of 9.23 mC m−2 is achieved in external charge excitation (ECE) TENG using 0.2 vol% PEI/P(VDF‐TrFE‐CFE) film, marking the highest charge density reported for single‐unit TENGs. This work provides novel material strategies for high‐performance TENGs, paving the way for their large‐scale practical applications.

Miao, Kanghua; Qin, Jundi; Lai, Siyuan; Luo, Mi; Kuchkaev, Aidar; Yakhvarov, Dmitry; Kang, Xiongwu

doi: 10.1002/adfm.202419989pmid: N/A

The engineering of the spin state and axial coordination of the metal center of single‐atom catalyst (SAC) represents an effective strategy for regulating the catalytic activity, selectivity, and stability toward electrocatalytic reduction of CO2 (ECO2R). However, rational design and deliberate fabrication of SACs with axial coordination of specified atoms remain challenging. Herein, Ni single atoms with axial coordination of phosphorus (NiP−N4−C) and four planar nitrogen atoms are fabricated, which induces reorientation of the 3d orbitals of the Ni atom and shift of the spin state from low (S = 0) to high (S = 2). The enhanced d−p orbital coupling between the Ni and the adsorbents enhances CO2 activation and reduces energy barrier for formation of *COOH, a key intermediate in the ECO2R to produce CO, enabling the high activity and near unity selectivity of CO in ECO2R in a broad potential range of 600 mV (−0.4–−1.0 V vs reversible hydrogen electrode vs RHE), achieving a turnover frequency of 37.2 s−1 at −1.0 V versus RHE. As a bifunctional cathode electrocatalyst, NiP−N4−C demonstrates a peak power density of 18.5 mW cm−2 and maintains cycling durability over 70 h in rechargeable Zn−CO2 batteries.

Jiang, Huilei; Zheng, Dingyu; Ye, Huijian; Xu, Lixin

doi: 10.1002/adfm.202418466pmid: N/A

Polymer film capacitors are widely utilized in electronics and power suppliers because of high power density and fast charge–discharge speed. Flexible polymer that tolerates the extremes of working temperature and electric field is essential for advanced energy storage systems. Here, hyperbranched polyethylene copolymer inoculated with N–hydroxyethyl maleimide (HBPE@HEPD) has been synthesized to modify boron nitride nanosheets (HEPD‐BNNSs) via non‐covalent interaction during liquid‐phase exfoliation. The conjugated double bond serves as trapping effect through the addition reaction with free radicals in HEPD‐BNNSs/polyetherimide (PEI) nanocomposite that delays the formation of electrical treeing at initial stage of breakdown. The resultant HEPD‐BNNSs/PEI film illustrates a superior energy storage capability, e.g. discharged energy density of 12.9 J cm−3 and efficiency >90% at 500 MV m−1 and room temperature are obtained in 0.5 wt.% nanocomposite, and discharged energy density of 5.8 J cm−3 under 100 °C with efficiency of 90.2% at 350 MV m−1 is achieved in current film. The prepared HEPD‐BNNSs/PEI nanocomposite also has eminent fatigue resistance at 200 MV m−1 with charge–discharge operation over 105 cycles. This strategy of trapping free radicals at initial stage of breakdown reveals a fresh prospect of polymer dielectrics for film capacitor.

Xiao, Junxiong; Zhan, Beibei; He, Mukun; Qi, Xiaosi; Zhang, Yali; Guo, Hua; Qu, Yunpeng; Zhong, Wei; Gu, Junwei

doi: 10.1002/adfm.202419266pmid: N/A

Multifunctionalization of electromagnetic wave absorbing materials (EMWAMs) presents a promising avenue for their application in complex scenarios. However, the effective integration of multiple supplementary functions into EMWAMs continues to pose a significant challenge. Herein, a novel nanofiber elastomer (NFE) incorporating multicomponent inorganic FeS2/S,N co‐doped carbon nanofibers (NFs) and organic component (Ecoflex) are designed and synthesized. The sulfur doping ratios and species can be effectively modulated via controlling the amount of sulfur and sulfurization temperature. The optimized FeS2/S,N co‐doped carbon NFs/Ecoflex NFE not only exerted an excellent impedance matching characteristic, but also displays boosted conductive loss and polarization loss capacities. Amongst, the designed NFE achieved an ultra‐wide effective absorption bandwidth (EAB) of 7.40 GHz and minimum reflection loss (RLmin) of −21.82 dB at the thin matching thickness (≈2.00 mm). Furthermore, FeS2/S,N co‐doped carbon NFs/Ecoflex NFE simultaneously presents greatly improved mechanical property, thermal insulation, hydrophobicity, and corrosion resistance. Through designing metastructures, the NFE with a periodically closed‐ring resonant structure realized an EAB of 32.64 GHz (ranging from 7.36 to 40.00 GHz). Overall, this research contributes valuable insights for the design of next‐generation EMWAMs with satisfactory multifunctionalities, demonstrating their significant potential for application in smart devices and challenging environments.

Lu, Lun; Li, Liangzhong; Chu, Mengxu; Chen, Cheng; Wang, Boya; Wang, Jun; Shen, Yi; Ma, Ruixue; Li, Bisheng; Shen, Liguo; Lin, Hongjun; Chen, Banglin

doi: 10.1002/adfm.202419433pmid:

Chen, Zhigang; Wang, Xiao; Liu, Juan; Liu, Kaizheng; Li, Shun; Wu, Mingming; Wu, Zhongqing; Wang, Zhenming; Shi, Yu; Ruan, Changshun

doi: 10.1002/adfm.202417836pmid: N/A

The physical microtopography, in an effective and stable manner, can powerfully confer biomaterials with enhanced osteoconduction for the repair of critical‐sized bone defects. However, the realization of the osteoconductive microtopography within a 3D porous scaffold is still unmet. Herein, this work presents a stone‐cottage‐inspired printing strategy to build microsphere patterned scaffolds with a tunable microtopography for accelerated bone regeneration. The customized composite inks of poly (lactic‐co‐glycolic acid) microspheres as “Stone” and alginate hydrogels as “Mortar” endow the fibers of as‐printed scaffolds with a stable and tunable groove‐ridge microstructure. Owing to this microtopography, microsphere patterned scaffolds significantly promote cell recruitment, immune response, angiogenesis, and osteogenesis. Meanwhile, compared to 55 and 85 µm, 25 µm width of groove‐ridge microstructure displays the most osteoconduction for repair of critical bone defects. Mechanistically, while cells prefer to adhere to microstructure with a bigger width and higher modulus in the early phase, this microstructure should also act as a barrier for cell growth and its smaller width is more beneficial for cell communication and differentiation in the later phase. Overall, it provides a robust strategy to fabricate the osteoconductive microtopography within a 3D scaffold, broadening the manipulation of physical morphology in tissue engineering.

Wu, Jiadong; Yang, Linyu; Wang, Shuying; Abliz, Ablat; Tuokedaerhan, Kamale; Li, Haibing; Li, Jie; Wang, Jun; Pan, Anqiang

doi: 10.1002/adfm.202419492pmid: N/A

Protective coatings for Zn anode are developed to suppress Zn dendrite growth, inhibit hydrogen evolution reaction (HER), and provide good anti‐corrosion properties. However, preparing protective coatings with all three of these characteristics remains a challenge. In this study, a triple‐functional amorphous In2O3 protective layer for Zn anodes is designed. The high redox potential of In/In3+ ensures the stability of the coating in aqueous electrolytes and effectively suppresses HER. Theoretical calculations indicate that the amorphous In₂O₃ protective layer has high Zn2⁺ affinity, which lowers the nucleation barrier for Zn2⁺ and suppresses dendrite growth. Furthermore, the anisotropy of this amorphous material provides homogeneous Zn2+ adsorption sites and enhances corrosion resistance. Consequently, amorphous In2O3@Zn symmetric batteries have excellent stability and a cycle life far exceeding that of bare Zn, showing the ability to undergo continuous stripping/plating at 1 mA cm−2 for >5400 h. At a current density of 10 A g−1, an amorphous In2O3@Zn//Ca‐V2O5 full cell retains a specific capacity of 307.3 mA h g−1 after 5000 cycles (cycle retention: 76%). The successful preparation of In2O3@Zn provides a new approach for obtaining highly stable and long‐life Zn anodes.

Zhao, Haicong; He, Xinyu; Yang, Jinghan; Liu, Min; Chen, Xue; Wang, Peiyi

doi: 10.1002/adfm.202418415pmid: N/A

Conventional bactericides struggle with biofilm barriers and inefficient deposition on hydrophobic leaves, resulting in undesirable control of plant bacterial diseases. To overcome these challenges, an innovative ferrocene‐based small‐molecule (FccA8R) is conceived, featuring biofilm disruption capabilities. Further optimizing FccA8R with seven‐membered oligosaccharide‐involved host–guest supramolecular strategy creates two kinds of biocompatible multifunctional supramolecular nanospheres (FccA8R@β‐CD and FccA8R@HP‐β‐CD). This manipulation efficiently eradicates mature biofilm barriers while enhancing droplet retention on hydrophobic leaves. At a concentration of 56.64 µg mL−1, the two materials remove Xanthomonas‐biofilms by 76.32–76.83%, notably surpassing that of single FccA8R (57.96%). Their versatility extends to the enhanced inhibition of bacterial motility, extracellular enzymes secretion, and exopolysaccharides production, all reducing the bacterial virulence. In vivo pot experiments, FccA8R@β‐CD and FccA8R@HP‐β‐CD demonstrate workable control efficacies of 48.91–52.03% against rice bacterial blight at 200 µg mL−1, superior to the commercial thiodiazole‐copper‐20%SC (36.42%) and FccA8R‐0.1%Tween (39.54%). Furthermore, these supramolecular assemblies disclose broad‐spectrum bactericidal efficacy (71.45–73.19%) against kiwifruit canker, significantly higher than thiodiazole‐copper‐20%SC (43.05%) and FccA8R‐0.1%Tween (57.24%). Besides, supramolecular bactericides are safe for plants and non‐target organisms like zebrafish and earthworms. Briefly, this research builds a key foundation for creating green bactericides from small‐molecule conception to eco‐friendly supramolecular assemblies, realizing the prevention of bacterial diseases and environmental safety.

Kuang, Zhenxin; Liu, Junchao; Meng, Weihao; Ikeda, Tomiki; Wang, Jingxia; Jiang, Lei

doi: 10.1002/adfm.202421111pmid: N/A

Azobenzene‐mesogen photo‐actuator is frequently utilized in diverse bionic motions due to their unparalleled advantages of wireless and reversible actuation. The realm of jumping behavior remains unexplored for azobenzene‐based actuators. Inspired by the Click‐beetles, here a Janus light‐driven jumping robot is achieved through the integration effect of an azobenzene molecule (with a short thermal relaxation time) and a splay alignment. The prepared Azobenzene liquid crystal films exhibit remarkable light‐driven continuous jumping capabilities, with jumping heights of 35 body lengths (BL) and takeoff speeds of 0.67 m s−1 (670 BL s−1), these data currently surpass the performance of small‐mass jumping robots. This research will be helpful for the design of novel actuators and broaden of the application scenarios of azobenzene actuators.