Surfactant-Assisted Synthesis of Semiconductor Hybrid Cd/Hg-Selenidostannates with Enhanced Optoelectronic and Piezoelectric Properties

Abstract

Multifunctional compounds have attracted significant attention for their wide-ranging applications in advanced technologies. In this study, we synthesized two semiconductor hybrid Cd/Hg-selenidostannates, (H2BPP)2CdSn3Se9 and (H2DMP)2Hg4Sn4Se17, employing 1, 3-bis(4-piperidinyl) propane and 1, 5-diamino-2-methylpentane through a surfactant-assisted thermal method. Remarkably, these hybrid chalcogenides are highly soluble in DMF, facilitating the formation of smooth, pinhole-free thin films via spin-coating method. (H2BPP)2CdSn3Se9 and (H2DMP)2Hg4Sn4Se17 films exhibit exceptional stability under high humidity and heat, with semiconducting band gaps of 2.12 eV and 2.21 eV, respectively. These band gaps enable strong light absorption and charge carrier generation, which directly contribute to their significant photocurrent responses. Specifically, Photocurrent measurements show Ilight of 1.5 µA cm⁻² and 1 µA cm⁻² at 0.8 V for (H₂BPP)₂CdSn₃Se₉ and (H₂DMP)₂Hg₄Sn₄Se₁₇, notably higher than the 0.30 mA cm² observed for the commercially available SnSe₂ electrode under the same conditions. Building on these interesting electrical properties, (H2BPP)2CdSn3Se9 also showed notable piezoelectric properties, resulting from its unique structural framework that supports both efficient charge transport and mechanical responsiveness. These promising stability and multifunctional characteristics highlight the potential of these hybrid selenidostannates for advanced optoelectronic and piezoelectric applications.