Elemental Tellurium Nanostructures: Controlled Synthesis and Emerging Applications in Photodetection, Electrocatalysis, and Photocatalysis

Elemental tellurium, a p-type semiconductor with a unique chiral chain structure, has attracted a surge of interest in its low-dimensional forms, including quantum dots, nanorods, nanowires, nanotubes, nanosheets, and nanofilms. These nanostructures exhibit outstanding properties such as a narrow bandgap, high carrier mobility, an anisotropic crystal structure, and large surface-to-volume ratios, making them attractive for optoelectronic and catalytic applications. This review presents a systematic and comprehensive overview of the latest advances in the controllable synthesis of tellurium nanostructures with diverse dimensionalities and morphologies, encompassing solution-phase and vapor-phase methodologies. The focus is on their burgeoning applications in photodetection, including discussions of their performance metrics, formation mechanisms, and structure-property-performance correlations across broadband spectral ranges from the ultraviolet to the mid-infrared. In addition, electrocatalysis, particularly for the hydrogen evolution reaction and photocatalysis for pollutant degradation and hydrogen evolution, is discussed, highlighting the critical roles of surface defects, morphological engineering, and electronic structure modulation in catalytic activity. Finally, the review assesses the current challenges, covering scalable production, catalytic performance, and environmental stability. Thus, we hope that this review can provide an outlook on future research directions, emphasizing the crucial structure-property-performance relationships that accelerate the practical application of elemental tellurium nanomaterials.