Data available on the thermoelectric properties of polycrystalline semiconductors are inconsistent, riddled with gaps, and ascribe stronger Seebeck effects to polycrystalline samples rather than single crystals. Here, by demonstrating the profound contribution of grain boundaries to the Seebeck voltage generation, we link the thermoelectricity in polycrystalline semiconductors to the grain boundary effects therein. The magnitude of this contribution is analytically related to the height and width of intergranular barriers, which are extrinsic properties in a polycrystalline sample and can be affected by external physicochemical parameters. Occurrences of chemo- and piezo-thermoelectric effects are analytically predicted and experimentally verified by the results of measurements on SnO₂ and ZnO samples with different nanostructures under various conditions. The presented model sets a platform for designing a range of novel Seebeck effect-based sensors, and unveils the potential of polycrystalline semiconductors with appropriately designed intergranular barriers as thermoelectric materials.

中文翻译：

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将多晶半导体中的热电生成与晶界效应联系起来，为基于新型塞贝克效应的传感器提供了平台

关于多晶半导体的热电特性的可用数据不一致，到处都是缝隙，并且使多晶样品而不是单晶具有更强的塞贝克效应。在这里，通过证明晶界对塞贝克电压产生的深远贡献，我们将多晶半导体中的热电与其中的晶界效应联系起来。这种贡献的大小在分析上与晶间势垒的高度和宽度有关，晶间势垒是多晶样品中的外在特性，并可能受外部理化参数的影响。化学和压电热电效应的发生可以通过对SnO ₂的测量结果进行分析预测和实验验证在不同条件下具有不同纳米结构的ZnO和ZnO样品。提出的模型为设计一系列新颖的基于Seebeck效应的传感器提供了平台，并揭示了具有适当设计的晶间势垒作为热电材料的多晶半导体的潜力。