rGO-Sb_(2)Se_(3)薄膜电化学共沉积制备及光电化学性能

Synthesis of rGO-Sb_(2)Se_(3) film through electrochemical co-deposition and photoelectrochemical performance

采用恒电位沉积法,在二元Sb-GO溶液体系中得到rGO-Sb预制层,在此过程中,GO被有效还原成rGO,并与Sb形成化学键。随后通过将预制层进行二段硒化热处理,快速去除多余的Se制备出rGO-Sb_(2)Se_(3)光阴极薄膜。通过XRD、SEM、Raman、XPS、UV-vis及PEC等手段对薄膜样品进行表征以及光电化学性能测试。结果表明:负载rGO使得rGO-Sb_(2)Se_(3)在700 nm以内的可见光区域的光吸收系数显著提升。rGO优良的导电性能及较高的载流子迁移率,可以快速转移电荷,抑制载流子的复合,因此光电化学性能以及光稳定性大大提高,光电流密度增大至接近Sb_(2)Se_(3)单相的2倍(−0.20 mA/cm^(2))。又因为rGO-Sb_(2)Se_(3)导带位置(−0.74 V vs.RHE)远负于析氢电位(0 V vs.RHE),故可作为一种新型光还原产氢的阴极,具备广阔的应用前景。

Using the potentiostatic electrodeposition method,the rGO-Sb pre-layer was obtained in the binary Sb-GO solution system,in which GO was effectively reduced to rGO,and there were chemical bonds forming between rGO and Sb nanoparticles,then the rGO-Sb pre-layer was transformed to rGO-Sb_(2)Se_(3) through a two-stage selenization treatment.The Sb_(2)Se_(3) and rGO-Sb_(2)Se_(3) composite film were characterized by XRD,SEM,Raman,XPS,UV-vis and carried out the photoelectrochemical test.The results indicate that the modification of rGO induces are markably increased light absorption coefficient within 700 nm in the visible light region.Due to the excellent conductivity and high carriers-mobility of rGO,it can quickly transfer charges and prevent the recombination of photo-induced carriers,so the photoelectrochemical performance and light-stability are significantly improved,and photocurrent density increases to nearly twice(−0.20 mA/cm^(2))as much as that of Sb_(2)Se_(3) film.Because the conduction band position(−0.74 V vs.RHE)of rGO-Sb_(2)Se_(3) is more negative than the hydrogen evolution potential(0 V vs.RHE),it can be applied as a novel photocathode used to photoreduce H2O to produce hydrogen,which has a promising prospect.