Aqueous rechargeable zinc-metal batteries are a promising candidate for next-generation energy storage devices due to their intrinsic high capacity, low cost, and high safety. However, uncontrollable dendrite formation is a serious problem, resulting in limited lifespan and poor coulombic efficiency of zinc-metal anodes. To address these issues, a 3D porous hollow fiber scaffold with well-dispersed TiO 2 , SiO 2 , and carbon is used as superzincophilic host materials for zinc anodes. The amorphous TiO 2 and SiO 2 allow for controllable nucleation and deposition of metal Zn inside the porous hollow fiber even at ultrahigh current densities. Furthermore, the as-fabricated interconnected conductive hollow SiO 2 and TiO 2 fiber (HSTF) possess high porosity, high conductivity, and fast ion transport. Meanwhile, the HSTF exhibits remarkable mechanical strength to sustain massive Zn loading during repeated cycles of plating/stripping. The HSTF with interconnected conductive network can build a uniform electric field, redistributing the Zn 2+ ion flux and resulting in smooth and stable Zn deposition. As a result, in symmetrical cells, the Zn@HSTF electrode delivers a long cycle life of over 2000 cycles at 20 mA cm −2 with low overpotential (≈160 mV). The excellent cycling lifespan and low polarization are also realized in Zn@HSTF//MnO 2 full cells.

Lithium–sulfur batteries (LSBs) are regarded as promising next‐generation energy storage systems owing to their remarkable theoretical energy density (2600 Wh kg‐1) and low cost. However, sluggish electrochemical kinetics, lithium polysulfides (LiPS) shuttling, and uncontrollable Li dendrite growth seriously hamper the commercial application of LSBs. Herein, dual‐functional 3D interconnected free‐standing fibers embedded with TiO2‐TiN heterostructures as an advanced skeleton are designed for concurrently regulating both the sulfur cathode (S/hollow TiO2‐TiN) and Li anode (Li/solid TiO2‐TiN). As a cathode skeleton, the hollow TiO2‐TiN fibers afford synergistic functions of chemical anchoring, physical confinement, and excellent electrocatalysis for LiPS. Meanwhile, the multifunctional skeleton with remarkable lithiophilicity and high conductivity can accomplish uniform Li deposition and homogeneous Li ion flux for inhibiting the growth of dendrites. Benefiting from these advantages, the full battery (S/hollow TiO2‐TiN || Li/solid TiO2‐TiN) exhibits excellent electrochemical performance, including high cycling stability (988.8 mAh g−1 after 200 cycles at 0.5 C) and impressive rate properties (639.3 mAh g−1 at 2 C). This work inaugurates a novel strategy from experimental and theoretical aspects for fabricating LSBs with robust electrochemical performance.

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devices, flexible substrates play a key role to fabricate high-performance electronics. In the past decade, various flexible substrates have been greatly developed. For instance, Chongwu and co-workers fabricated silver nanowire films on flexible polyethylene terephthalate (PET) substrates with good mechanical flexibility and demonstrated the application in a touch panel. [7] Johansson and co-workers reported a polyethylene naphthalate (PEN) substrate coated by Ag nanowire network for an extremely lightweight and ultraflexible colloidal quantum dots solar cell. [8] Jeong and co-workers fabricated copper conductors on polyimide and polyethersulfone substrates, exhibiting the potential accessibility for flexible electronics. [9] The abovementioned flexible substrates exhibit excellent stretchable ability and high-flexible performance. Because of their excellent mechanical and chemical stability, it takes extremely long time for them to degrade or decompose in the nature, leading to environmental pollution. Therefore, more and more attention is paid to looking for flexi ble, biocompatible, and environmentally friendly biomass substrates for wearable devices. [6,[10][11][12][13] Flexible biomass substrates based on nanofibrillated cellulose have been explored and are expected to be used in wearable electronics due to their excellent mechanical properties, renewability, and raw material abundance. Ma and co-workers successfully fabricated gallium arsenide microwave devices on flexible wood-derived cellulose nanofibril paper. [14] Ju and co-workers reported flexible, transparent phototransistors on biodegradable wood-derived cellulose nanofibrillated fiber substrates toward environment friendly electronics. [15] Hu and co-workers fabricated flexible organic field-effect transistors on tailorable softwood-derived nanopapers. [16] These successful studies suggest the feasibility to fabricate environment friendly cellulose-based substrates for flexible electronics, and further accelerate development of the flexible wearable devices.Currently flexible perovskite solar cells (PSCs) have gained wide attention by their excellent performance and potential application in wearable energy devices. [13,[17][18][19] As is well known, high performance flexible perovskite devices are still based on nonbiocompatible and nondegradable plastic substrates such as PET, PEN, and polydimethylsiloxane. Yu and co-workers first reported flexible perovskite solar cells fabricated on Wearable devices are mainly based on plastic substrates, such as polyethylene terephthalate and polyethylene naphthalate, which causes environmental pollution after use due to the long decomposition periods. This work reports on the fabrication of a biodegradable and biocompatible transparent conductive electrode derived from bamboo for flexible perovskite solar cells. The conductive bioelectrode exhibits extremely flexible and light-weight properties. After bending 3000 times at a 4 mm curvature radius or even undergoing a crumpling test, it still shows excellent e...