Organic/inorganic hybrids suffer from low power factor (⁠|${S^2}\sigma $|⁠) due to the anticorrelation between Seebeck coefficient (S) and electrical conductivity (⁠|$\sigma $|⁠). Energy-filtering effect becomes a promising way to trade off S and |$\sigma $|⁠. Herein, we propose an effective method that constructs the heterogeneous interfaces containing the gradient potential barrier to greatly enhance the interfacial energy-filtering effect. Comparing with the conventional random and uniform configuration, the gradient potential barrier is capable of increasing S but significantly suppressing the decrease in |$\sigma $|⁠, thereby improving |${S^2}\sigma $|⁠. The as-synthesized proof-of-concept PANI-(TiO₂-CF) thermoelectric material that possesses the ternary interfaces with descending barrier enables a 4.8-fold increase in S while just a 9.3-fold reduction in |$\sigma $|⁠, resulting in a 2.43-fold improvement in power factor, proving the conceptual feasibility. In addition, the synergetic phonon scattering at ternary interfaces conducts a quite low k of 0.226 W m⁻¹ K⁻¹. It is found that the 20% PANI-80% (35% TiO₂–65% CF) demonstrates the maximum power factor and figure of merit of 359.56 μ W m⁻¹ K⁻² and 0.48 at room temperature, respectively. More importantly, the as-prepared PANI-(TiO₂-CF) also illustrates the high flexibility together with the excellent chemical and physical durability. Moreover, a thermoelectric device that uses the PANI-(TiO₂-CF) and PEI-doped MWCNT films as respectively p- and n-type components shows a maximum output power about 3.1 μW at the temperature difference of 30 K. This work provides a unique interfacial methodology to reinforce the energy-filtering effect, suggesting great potential for boosting thermoelectric hybrids.

中文翻译：

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通过梯度配置构建界面势垒：一种增强能量过滤效果的有效方法

由于塞贝克系数 ( S ) 和电导率 ( ⁠|$\sigma $|⁠ )之间的反相关性，有机/无机混合体的功率因数较低 ( ⁠|${S^2} \sigma $|⁠ )。能量过滤效应成为权衡S和|$\sigma $|⁠ 的一种很有前景的方法。在此，我们提出了一种构建包含梯度势垒的异质界面以大大增强界面能量过滤效果的有效方法。与传统的随机和均匀配置相比，梯度势垒能够增加S但显着抑制|$\sigma $|⁠ 的减少，从而提高|${S^2}\sigma $|⁠。合成的概念验证 PANI-(TiO ₂ -CF) 热电材料具有带下降势垒的三元界面，使S增加 4.8 倍，而|$\sigma $|⁠仅减少 9.3 倍，导致功率因数提高了 2.43 倍，证明了概念上的可行性。此外，三元界面处的协同声子散射传导的k非常低，为 0.226 W m ^-1 K ^-1。发现 20% PANI-80% (35% TiO ₂ –65% CF) 的最大功率因数和品质因数为 359.56 μ W m ^-1 K ^-2和室温下分别为 0.48。更重要的是，制备的PANI-(TiO ₂ -CF) 还展示了高柔韧性以及优异的化学和物理耐久性。此外，使用 PANI-(TiO ₂ -CF) 和 PEI 掺杂的 MWCNT 薄膜分别作为 p 型和 n 型组件的热电器件在 30 K 的温差下显示出约 3.1 μW 的最大输出功率。一种独特的界面方法来加强能量过滤效应，表明促进热电混合动力的巨大潜力。