华南理工大学刘军团队JACS:Ah级宽温域(-50 ~ 60 ℃)准固态锌空气电池

B站影视 电影资讯 2025-03-27 07:58 1

摘要:美国能源部指出,电池技术亟需在高能量密度(>300Wh kg-1)、高安全性、高性价比(US $75 kWh-1)、耐高低温(-30 ~ 60 ℃)、寿命预测与安全性预测等方向实现突破。准固态锌空气电池可以很好地满足这些目标,因为其具有多电子氧化还原反应和固有

美国能源部指出,电池技术亟需在高能量密度(>300Wh kg-1)、高安全性、高性价比(US $75 kWh-1)、耐高低温(-30 ~ 60 ℃)、寿命预测与安全性预测等方向实现突破。准固态锌空气电池可以很好地满足这些目标,因为其具有多电子氧化还原反应和固有的安全特性,可以实现较高的理论能量密度。然而,一些关键问题,如对高性能双功能阴极、准固态电解质、可逆阳极、高速率能力和宽温度范围的操作的需求仍然是阻碍其实际实现的最严重限制。

为实现准固态锌空气电池商业化,华南理工大学刘军团队提出了一种基于高熵合金空气阴极催化剂与双网络有机水凝胶电解质协同设计的策略,其理论依据如下:首先,高熵策略为克服活性权衡提供了最优解决方案。传统电催化剂通常依赖单一活性组分,难以满足多功能需求,而高熵合金的多元素协同效应可提供丰富的吸附活性位点,是实现多功能催化反应的理想选择。其次,通过添加二甲亚砜构建多个分子间氢键结合的双网络有机水凝胶,展现出优异的抗冻性(-50℃)与化学/机械稳定性。基于此,本研究提出了一种集成MnFeCoNiRu/CNF阴极与P(AA-co-AM)有机水凝胶电解质的准固态锌空气电池体系,其单电池容量高达7.15 Ah,能量密度达110 Wh kgcell⁻¹,可在500 mA及250/500 mAh条件下稳定循环,并兼具机械柔性与宽温域工作范围(-50至60℃)的特性。该研究以题为“Ampere-Hour-Scale Quasi-Solid-State Zinc-Air Batteries with a Wide Operating Temperature Range (-50 to 60 °C)”的论文发表在最新一期《Journal of the American Chemical Society》上。博士生顾腾腾为论文第一作者,刘军为论文通讯作者

本文要点

1、MnFeCoNiRu/CNF的合成与表征

单相固溶体MnFeCoNiRu高熵合金纳米颗粒嵌入碳纳米纤维(MnFeCoNiRu/CNF)的制备工艺包括静电纺丝技术及后续石墨化处理。扫描和透射电子显微镜显示碳纳米纤维相互交织且直径介于150 ~ 200 nm之间,并且尺寸约为5~20 nm的MnFeCoNiRu纳米颗粒均匀地嵌入碳纳米纤维中。电感耦合等离子体发射光谱对MnFeCoNiRu/CNF的元素组成分析表明,HEA中金属原子比例为Mn: Fe: Co: Ni: Ru= 18: 24: 21: 21: 16,接近1:1。

Figure 1. Characterization of MnFeCoNiRu/CNF. (a) SEM and (b) TEM images of MnFeCoNiRu/CNF. (c) Average diameters of the MnFeCoNiRu HEA NPs supported on CNF. (d) HRTEM images of MnFeCoNiRu/CNF. (e) HAADF-STEM and the associating STEM-EDX mapping images of MnFeCoNiRu/CNF. (f) Mass loadings of each metal element in MnFeCoNiRu/CNF. (g) XRD patterns of MnFeCoNiRu/CNF. (h) Mn K-edge XANES and (k) FT-EXAFS spectra of MnFeCoNiRu/CNF, MnO2, and Mn foil. (i) Ni K-edge XANES and (l) FT-EXAFS spectra of MnFeCoNiRu/CNF, NiO, and Ni foil. (j) Ru K-edge XANES and (m) FT-EXAFS spectra of MnFeCoNiRu/CNF, RuO2, and Ru foil.

2、电催化性能

所提出的MnFeCoNiRu/CNF具有出色的双功能活性(ΔE = 0.64 V)和稳定性(>10,000循环)。

Figure 2. Electrochemical performance of electrocatalysts. (a) LSV curves of CNF, FeCoNi/CNF, MnFeCoNi/CNF, FeCoNiRu/CNF, MnFeCoNiRu/CNF, Ru/CNF, and commercial Pt/C for the ORR. (b) Comparison of E1/2 and Jk at 0.2 V (vs. RHE). (c) ORR polarization curves before and after 10000 cycles of MnFeCoNiRu/CNF. (d) LSV curves of CNF, FeCoNi/CNF, MnFeCoNi/CNF, FeCoNiRu/CNF Ru/CNF, and RuO2 for the OER. (e) Tafel slope plots of CNF, FeCoNi/CNF, MnFeCoNi/CNF, FeCoNiRu/CNF Ru/CNF, and RuO2. (f) OER polarization curves before and after 10 000 cycles of MnFeCoNiRu/CNF. (g) ORR/OER bifunctional LSV curves of different catalysts along with the combination of commercial Pt/C and RuO2. (h) ORR and OER bifunctional activities of MnFeCoNiRu/CNF and some representative electrocatalysts in references.

3、ZAB-MnFeCoNiRu/CNF。

通过引入二甲基亚砜(DMSO)修饰多重分子间氢键网络的聚丙烯酰胺-丙烯酸共聚物(P(AA-co-AM))有机水凝胶表现出优异的抗冻性(-50℃)与化学/机械稳定。此外,双链聚合物P(AA-co-AM)有机水凝胶电解质可在一定程度上抑制副反应,减缓Zn枝晶的形成,通过调节氢键和阳离子溶剂化结构显著改善电化学界面的稳定性。

Figure 3. Characterization of the organohydrogel electrolyte. (a) Interaction between a water molecule and various polyelectrolyte backbones was calculated using DFT. (b) Stress−strain curves of H-P(AA-co-AM) and O-P(AA-co-AM) polyelectrolytes with tensile testing. (c) SEM image displays the structure of the freeze-dried O-P(AA-co-AM) hydrogel. Ex situ XRD patterns of Zn anode plates after cycling tests under the symmetric Zn||Zn cells employing (d) H-P(AA-co-AM) and (e) O-P(AA-co-AM) polyelectrolytes at 2 mA cm-2 (1 mAh cm-2). (f, g) TOF-SIMS cross projection and TOF-SIMS 3D reconstruction images of CN−, S−, ZnO−, and ZnO−species after 12 cycles in O-P(AA-co-AM). (h) Cycling performance of the symmetric Zn || Zn cells using an O-P(AA-co-AM) polyelectrolyte at 10 mA cm-2. (i) Ionic conductivity of the KOH-filled O-P(AA-co-AM) polyelectrolyte under different temperatures.

我们使用MnFeCoNiRu/CNF作为阴极,O-P(AA-co-AM)作为电解质,锌箔作为阳极组装了柔性锌空气电池(表示为ZAB-MnFeCoNiRu/CNF)。该电池在30 °C下展现出优异的高倍率循环性能,并具有较宽的温度适应性。

Figure 4. Electrochemical performance of the MnFeCoNiRu/CNF-based quasi-solid-state ZABs at different temperatures. (a) Open-circuit voltages and (b) discharging plateaus at current densities ranging from 1 to 100 mA cm-2 ZAB-MnFeCoNiRu/CNF and ZAB-Pt/C+RuO2 at 30 °C. (c) Charge/discharge profiles of ZAB-MnFeCoNiRu/CNF and ZAB-Pt/C+RuO2 at 30 °C. Galvanostatic cycling stability at (d) 10 mA cm-2 and (e) 50 mA cm-2 ZAB-MnFeCoNiRu/CNF and ZAB-Pt/C+RuO2 at 30 °C (time constraint: 20 min per cycle). (f) Discharge and power density plots of ZAB-MnFeCoNiRu/CNF at different temperatures. (g) Cycling tests of ZAB-MnFeCoNiRu/CNF at 5 mA cm-2 and at different temperatures (time constraint: 20 min per cycle). (h) Comparison of the electrochemical performance of ZAB-MnFeCoNiRu/CNF at different temperatures.

首次展示了商业上可行的安培级准固态锌空气电池,该电池具有超高的电池级容量(7.15 Ah)和110 Wh kgcell-1的能量密度,在500 mA和250/500 mAh的电导下循环,机械灵活性和宽工作温度范围(-50 ~ 60℃)的特性。

Figure 5. Electrochemical performance of ampere-hour-scale QSSZABs. (a) Open-circuit voltages and optical images of ampere-hour-scale QSSZABs. (b) Galvanostatic discharge performance of QSSZABs with a constant input current of 500.0 mA. (c, d) Rate performance of QSSZABs. (e) LSV curves and the computed output power of QSSZABs. (f, g) Galvanostatic cycling curves of QSSZABs with an input current of 500.0 mA and a capacity of 0.25/0.5 Ah.

4、多功能电催化机理

MnFeCoNiRu/CNF电极具有多个活性位点,通过原位拉曼可以观察到材料在放电和充电区域的不同信号。DFT计算表明,在FeCoNi中加入Mn和Ru原子可以将价电子提供给周围的空穴位点,从而减弱了吸附质与合金表面之间的耦合强度。

Figure 6. In situ electrochemical Raman analysis and theoretical calculations. (a, b) Operando electrochemical Raman spectra obtained for MnFeCoNiRu/CNF and FeCoNi/CNF during discharging and charging processes in a 6.0 M KOH electrolyte. (c) Charge density variation and spin density. (d) Spin magnetic moment *O2 and the metal. (e) 2D electronic potential maps (along the x y-plane). (f) d-band center. Gibbs free energy diagrams of (g) ORR and (h) OER on FeNi3, FeCoNi, MnFeCoNi, and MnFeCoNiRu.

5、总结

本研究首次报道了安时级准固态锌空气电池,其展现出超高电池级容量(7.15 Ah)和能量密度110 Wh kgcell-1,可在500 mA及250/500 mAh条件下稳定循环,并兼具机械柔性与宽温域工作范围(-50至60 ℃)。材料创新体现在两个方面,一方面,通过静电纺丝与石墨化工艺结合,成功制备MnFeCoNiRu高熵合金纳米颗粒嵌入碳纳米纤维(MnFeCoNiRu/CNF)双功能催化剂。原位拉曼光谱证实该材料在充放电过程中会暴露多个活性位点,密度泛函理论(DFT)计算表明,在合金FeCoNi中引入元素Mn和Ru可向邻近空位提供价电子,削弱吸附质与合金表面的相互作用强度。另一方面,双链聚合物P(AA-co-AM)有机水凝胶电解质通过调控氢键网络和阳离子溶剂化结构,有效抑制副反应并缓解锌枝晶生长,显著提升电化学界面稳定性。总之,这一安时级准固态锌空气电池的提出,推动了柔性准固态锌空气电池的实用化进程,为全固态电池的产业化发展注入了新动能。

声明:仅代表作者个人观点,作者水平有限,如有不科学之处,请在下方留言指正!

来源:老齐讲科学

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