Shin Donghyeop, Ngaboyamahina Edgard, Zhou Yihao, Glass Jeffrey T, Mitzi David B
Department of Mechanical Engineering and Materials Science, Duke University , Durham, North Carolina 27708, United States.
Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
J Phys Chem Lett. 2016 Nov 17;7(22):4554-4561. doi: 10.1021/acs.jpclett.6b02010. Epub 2016 Nov 1.
CuBaSnSSe films consisting of earth-abundant metals have been examined for photocathode application. Films with different Se contents (i.e., CuBaSnSSe with x ≤ 2.4) were synthesized using a cosputter system with post-deposition sulfurization/selenization annealing treatments. Each film adopts a trigonal P3 crystal structure, with progressively larger lattice constants and with band gaps shifting from 2.0 to 1.6 eV, as more Se substitutes for S in the parent compound CuBaSnS. Given the suitable bandgap and earth-abundant elements, the CuBaSnSSe films were studied as prospective photocathodes for water splitting. Greater than 6 mA/cm was obtained under illumination at -0.4 V versus reversible hydrogen electrode for Pt/CuBaSnSSe films with ∼60% Se content (i.e., x = 2.4), whereas a bare CuBaSnSSe (x = 2.4) film yielded ∼3 mA/cm at -0.4 V/RHE.
由储量丰富的金属组成的CuBaSnSSe薄膜已被用于光阴极应用的研究。使用带有沉积后硫化/硒化退火处理的共溅射系统合成了具有不同硒含量的薄膜（即x≤2.4的CuBaSnSSe）。随着更多的硒在母体化合物CuBaSnS中替代硫，每一个薄膜都采用三方P3晶体结构，晶格常数逐渐增大，带隙从2.0 eV 移动到1.6 eV。鉴于合适的带隙和储量丰富的元素，CuBaSnSSe薄膜被作为水分解的潜在光阴极进行研究。对于硒含量约为60%（即x = 2.4）的Pt/CuBaSnSSe薄膜，在相对于可逆氢电极-0.4 V的光照下，获得了大于6 mA/cm² 的电流，而裸CuBaSnSSe（x = 2.4）薄膜在-0.4 V/RHE时产生约3 mA/cm² 的电流。
