Retraction: Constructing interfacial potential barrier via a gradient configuration: an effective method to enhance energy-filtering effect.

Abstract

Abstract 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.