fig1

Figure 1. (A, B) Schematic illustration of the carriers and phonons in the presence of hierarchical structures, and the effect of various scattering mechanisms at 300 K^[50], Copyright 2022 Springer Nature. (C) schematic of the variation of bond angle, a semi-ordered zigzag nanostructure, energy band sharpening, and convergence by the charge transfer engineering^[26] Copyright 2023 Advancement of Science. (D) mechanisms revealing the reduction of thermal conductivity for TE conversion; bulk and reduced-dimension configurations, and NPM configuration respectively^[51]. Copyright 2023 Wiley-VCH GmbH. NPM: nanophononic metamaterial.