As an earth-abundant and environmentally friendly material,tin sulfide(SnS)is not only a high-performance photovoltaic material,but also a new promising thermoelectric material.Despite extensive research on the thermo...As an earth-abundant and environmentally friendly material,tin sulfide(SnS)is not only a high-performance photovoltaic material,but also a new promising thermoelectric material.Despite extensive research on the thermoelectric properties of this material in recent years,the room-temperature thermoelectric figure of merit(ZT)of SnS has not been broke through 2[2022 Sci.China Mater.651143].In this work,based on a combination of density functional theory and non-equilibrium Green’s function method,the electronic and thermoelectric properties in SnS-nanoribbon-based heterojunctions are studied.The results show that although SnS nanoribbons(SNSNRs)with zigzag edges(ZSNSNRs)and armchair edges(ASNSNRs)both have semiconductor properties,the bandgaps of ASNSNRs are much wider than those of ZSNSNRs,which induces much wider conductance gaps of𝑁N-ASNSNR(N is the number of tin-sulfide lines across the ribbon width)).In the positive energy region,the ZT peaks of𝐿L-SNS-Au are much larger than those of𝐿L-SNS-GNR(L represents the number of longitudinal repeating units of SNSNR in the scattering region).While in the positive energy region,the ZT peaks of L-SNSGNR are larger than those of L-SNS-Au.Further calculations reveal that the figure of merit will be over 3.7 in L-SNS-Au and 2.2 in L-SNS-GNR at room temperature,and over 4 in L-SNS-Au and 2.6 in L-SNS-GNR at 500 K.展开更多
基金supported by the key projects of Hunan Provincial Department of Education(Grant No.21A0167)the Hunan Provincial Natural Science Foundation of China(Grant No.2019JJ40532)+1 种基金the National Natural Science Foundation of China(Grant Nos.11704417,11974106,and 11247030)the Talent Introducing Foundation of Central South University of Forestry and Technology(Grant No.104-0160)。
文摘As an earth-abundant and environmentally friendly material,tin sulfide(SnS)is not only a high-performance photovoltaic material,but also a new promising thermoelectric material.Despite extensive research on the thermoelectric properties of this material in recent years,the room-temperature thermoelectric figure of merit(ZT)of SnS has not been broke through 2[2022 Sci.China Mater.651143].In this work,based on a combination of density functional theory and non-equilibrium Green’s function method,the electronic and thermoelectric properties in SnS-nanoribbon-based heterojunctions are studied.The results show that although SnS nanoribbons(SNSNRs)with zigzag edges(ZSNSNRs)and armchair edges(ASNSNRs)both have semiconductor properties,the bandgaps of ASNSNRs are much wider than those of ZSNSNRs,which induces much wider conductance gaps of𝑁N-ASNSNR(N is the number of tin-sulfide lines across the ribbon width)).In the positive energy region,the ZT peaks of𝐿L-SNS-Au are much larger than those of𝐿L-SNS-GNR(L represents the number of longitudinal repeating units of SNSNR in the scattering region).While in the positive energy region,the ZT peaks of L-SNSGNR are larger than those of L-SNS-Au.Further calculations reveal that the figure of merit will be over 3.7 in L-SNS-Au and 2.2 in L-SNS-GNR at room temperature,and over 4 in L-SNS-Au and 2.6 in L-SNS-GNR at 500 K.
