ENERGY CONVERSION AND MANAGEMENT
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2023
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IF 10.4
Huping Yan,Zhen Liu,Ronghui Qi
Utilizing ambient humidity to drive electron motion in nanomaterials and generate usable electricity is promising for self-powered electronics and sensors. This paper developed a humidity gradient-driven microgenerator (HGDM) by coating a cobalt hydrogel on part of the TiO 2 nanoparticle film and employing multi-walled carbon nanotubes as electrodes. The humidity gradient was established between the bottom hygroscopic hydrogel and the top electrode in contact with ambient air. Results demonstrated that the TiO 2 /Co hydrogel HGDMs can achieve an open-circuit voltage of 0.95 V at 20 °C and 50–80% relative humidity (RH). The single generator (size: 5 × 4 cm 2 ) exhibited a current output of approximately 0.1 mA, which remained stable for over 100 h with less than 1% decay. The increase in hydrogel films’ height first increased then decrease the performance, and the optimal value was provided. By alternately introducing 10% and 80% RH air humidity cycles, the generator responded rapidly with a wet/dry output ratio over 400, and the delay time maintained within 1.0 s after 1000 cycles. The output performance dropped severely when the air temperature was higher than 40 °C. In practical applications, a series of 5–7 micro-generators successfully delivered consistent power supply to LED lights and calculators for a duration exceeding one week, and the voltage output can be recovered to its initial value after less than 5 h of recharging. Mechanistic studies have revealed that the primary driving force for power generation is the humidity gradient rather than vapor evaporation. Because the diameter of the nanopores (around 200 nm) are much smaller than the Debye length of the double electric layer (960 nm), ion-selective permeability in TiO 2 nanochannels is also important which can prevent nearly 90% OH – from passing through the channels. This hydrogel microgenerator exhibits wide-ranging application prospects, and our study contributes to enhancing its performance and elucidating the mechanism.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
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IF 19
Xinpeng Che,Ting Wang,Bailang Zhang,Zhuanzhuan Zhai,Yijun Chen,Danfeng Pei,Anle Ge,Mingjie Li,Chaoxu Li
Harvesting electricity from ubiquitous atmospheric moisture has drawn growing research attention. Despite great advances, moisture generators still suffer from performance decay during long-term service. Recently, self-oscillating actuators driven by humidity gradience have attracted great interests, which may give a clue to harvest energy persistently via electromagnetic induction. In order to combine high electric conductivity with self-oscillating actuators, bimorph composites of 2D conductive MXene with liquid metal (i.e., EGaIn) are designed. In presence of marine alginate, EGaIn droplets can be encapsulated by MXene nanosheets in their suspension. And simple liquid-casting can produce biomorph actuating films with top MXene-rich layer and bottom EGaIn-rich layer of self-sintered EGaIn droplets. When exposing to a humidity gradience (e.g., 20% cm −1 ), this biomorph actuator can oscillate persistently with an actuating speed of ≈260° s −1 and a frequency of ≈0.5 Hz, while without any human intervention. Under a magnetic field (e.g., intensity ≈0.5 T), this self-oscillating behavior can generate an alternating faradic current with an amplitude of at least 1360 µA m −2 . Thus, this study may not only provide an alternative pathway for producing self-oscillating and conductive actuators, but also offer a new strategy for persistent energy harvest from atmospheric moisture.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 37
·19269-19277
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IF 11.301
Tian Yang,Honglin Yuan,Sitong Wang,Xuhan Gao,Huhu Zhao,Pengying Niu,Beibei Liu,Bo Li,Huanjun Li
Natural water evaporation is a ubiquitous resource at the Earth's surface. Actuating materials that convert such evaporation energy into mechanical motions are highly desirable but challenging. Herein, tough nacre-mimetic films featuring excellent dry/wet tensile strength (294.4 MPa/182.3 MPa) are reported. Benefiting from this feature, the resultant film actuators can not only perform fast flipping motion and lasting oscillation driven by natural evaporation, but also undergo rapid turnover upon exposure to small humidity gradients on the palm of the hand. Importantly, the film actuators further exhibit exceptional actuation without fatigue when exposed to thermal water vapors. Furthermore, it is demonstrated that the stretch-induced oriented film could be used to construct a self-powered soft robot driven by water gradients. As a proof of concept, a natural evaporation-driven generator is assembled by connecting the actuators with a piezoelectric element to power a LED. These demonstrations clearly show that the biomimetic films are promising for harnessing natural evaporation to drive various self-powered devices.
研究领域:
材料科学
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能源技术
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仿生学
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
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2025
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IF 12.5
Houkai Huang,Wenjing Li,Juncheng Wei,Yiqiang Wu,Dongying Hu,Fangchao Cheng
Moist-electric generation typically exploits water molecule diffusion or ionic concentration gradients, but constructing highly differentiated hydrophilic-hydrophobic surfaces for efficient power generation remains challenging. To address this, we developed a highly stable cellulose film matrix with superior moisture response via a dual-crosslinked strategy. Crucially, this achieves bionic in-situ calcification through forming a CaCO 3 surface layer. Sequentially, this robust matrix facilitates the creation of a stable hydrophilic-hydrophobic differential surface to fabricate a sandwich-structured LiCl/DNF/CaCO 3 -SiO 2 transparent film. The resulting thin film (40 μm) device sensitively detects ambient humidity changes. A single component achieves a sustained open-circuit voltage of 1.5 V . It can charge a 10 μF capacitor to 10 V within 1 h, powering small devices like light bulbs and calculators. The enhanced water contact angle difference of 131° between surfaces significantly boosts the humidity gradient and electrochemical output. This work demonstrates the feasibility of powering small electronics and provides a novel pathway for green, high-performance energy-harvesting film devices and lightweighting units.
研究领域:
材料科学
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纳米技术
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能源材料
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环境响应材料
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生物基材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
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2025
·
IF 26.8
Huiyu Yang,Xiaohua Cheng,Liangang Zhao,Xiangyi Zhang,Bin Lu,Zhengfei Tan,Hai Liu,Liangjun Xia,Weilin Xu
Harvesting electrical energy from the ubiquitous water cycle to power flexible electronic devices is receiving increasing attention. However, the development of moisture-driven generators with high and stable power output remains a significant challenge. Here, we design a photothermal evaporation-driven moisture generator (PEMG) that modifies a cotton fabric with in situ polymerized pyrrole by a polydopamine (PDA)-structured color film to form an asymmetric photothermal temperature gradient. The PDA asymmetric photothermal layer not only effectively addresses the issue of insufficient sustained power generation caused by water adsorption saturation but also mitigates the unstable moisture gradient resulting from excessive water evaporation. CF@PPy@PDA (purple) achieved an open-circuit voltage ( V oc ) of 0.74 V and a short-circuit current ( I sc ) of 0.72 mA under 60% relative humidity (RH) and 1-sun illumination, respectively. White LED bulbs emit a steady stream of light for more than 24 h. Moreover, the V oc of the PEMG (six units in series) reaches 1.18 V at an average solar intensity of 1000 W m −2 and 43% RH, while the V oc is 0.72 V at night (52% RH). Meanwhile, wearable systems designed with integrated PEMG units provide sufficient power supply for electronic devices under natural conditions.
研究领域:
能源材料
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纳米技术
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环境能量采集
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可穿戴电子
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
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IF 8.3
Xiuli Xie,Xiaotong Wang,Yang Zhang,Long Fang,Jiangshan Feng,Shaohong Liu,Dingshan Yu,Fangming Zhu,Xudong Chen
Herein, we develop a new intelligent moisture-sensitive hybrid aerogel by evenly embedding a proton-conductive covalent organic framework (COF-2SO3H) into a carboxylated cellulose nanofiber network (CNF-C) for water harvesting and spontaneous sustained electricity production from ambient humidity and human respiration. Our strategy first exploits the “suspending agent” role of CNF-C to stably disperse COF materials in water for forming uniform hierarchical hybrid structures. By utilizing the synergy of COF-2SO3H and CNF-C together with their inherent structure merits and surface group effects, the hybrid aerogel displays increased water uptake and ion conductivity. Upon asymmetric moisturization, it can create a self-maintained moisture gradient to engender a concentration difference for mobile Na+ and H+, resulting in efficient charge separation and diffusion. Thus, the hybrid aerogel-based coin-type generator achieves a continuous output voltage of ∼0.55 V for at least 5 h in ambient environments in contrast to that using pure CNF-C and carbon-based generators with transient voltage response. Intriguingly, the wearable generator with an aerogel in a mask is more sensitive to human respiration and achieves repeatable and reliable self-charge for persistent electricity along with an increased output voltage of up to 1.0 V and much faster self-charge (only 3 min), both of which surpass most reported moisture-enabled generators.
研究领域:
材料科学
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能源
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环境科学
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纳米技术
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）