stability of an borophane allotrope. W-borophane, the most stable allotrope of the hydrogenated borophene, has energy about 113.41 meV per atom, lower than that of C-borophane  [@WangRSC17].

Thermoelectric materials, based on a fundamental interplay between their electronic and thermal performance, have attracted much interest for energy efficient device applications [@Dresselhaus93; @Harman; @Venkatasubramanian; @Arita; @Hamada; @Zide; @Wei; @Zuev; @Kato; @Buscema; @Konabe1]. The efficiency of the refrigeration or power generation devices is characterized by a dimensionless figure of merit ${\it ZT}=\frac{\sigma\mathcal{S}^{2}}{\mathcal{K}}T$, in which $\sigma,\mathcal{K}$ and $\mathcal{S}$ are electrical conductivity, thermal conductivity and Seebeck coefficient (thermopower), respectively and $T$ is absolute temperature. The small thermal conductivity and relatively high thermopower and electrical conductivity are required for high-efficiency thermoelectric materials. Even if the Seebeck coefficient becomes large, a heat current inevitably accompanies a temperature gradient and thus makes a tradeoff.

Therefore, a great deal of efforts has been carried out to improve the thermoelectric performance through balancing these interdependent thermoelectric parameters. There are completely different routes to improve the thermoelectric figure of merit, which are tailoring to improve the power factor ($\sigma\mathcal{S}^{2}$) and lowering the thermal conductivity.

A hallmark of the thermoelectric materials study came actually from the pioneering work [@Dresselhausprb47-93-1], proposing that nanostructuring 