Band offset of SnS solar cell structure measured by X-ray photoelectron spectroscopy

Enhancing the efficiency of SnS solar cells via band-offset engineering with a zinc oxysulfide buffer layer

“…SnS/CdS forms a type-II heterojunction with the CBO (ΔE c = χ SnS -χ CdS , where χ is electron affinity) of −0.4 eV, which is an unfavorable band alignment for making efficient solar cells. 20 According to device simulations, a large negative CBO gives rise to an increase in the interface recombination, while a large positive CBO greater than +0.5 eV creates a barrier in the conduction band that impedes the collection of photo-generated electron. 21,22 Thus, a small positive CBO is desirable to reduce interface recombination without any loss in photo-current collection.…”

Optoelectronic properties of single-layer, double-layer, and bulk tin sulfide: A theoretical study

“…8,35 The measured properties of SnS samples depend on the synthesis route. 9,[36][37][38][39] Theory and atomistic simulation can contribute significantly in clarifying how the properties of SnS and other layered semiconductors depend on the atomicscale structural features. 12,25,27,30,32,40,41 Here, we use firstprinciples calculations based on density functional theory and the GW approximation to the electron self-energy to study trends in the electronic and optical properties of model single-layer, double-layer, and bulk structures of SnS.…”

Band alignment of SnS/Zn(O,S) heterojunctions in SnS thin film solar cells

“…15 The prevalent low efficiencies can be attributed to various sources, such as bulk material impurities and defects, interface trap states, and notably unfavorable heterojunction band alignment. 16 Theory suggests that a small positive conduction band offset (CBO) in the range of 0 eV to þ0.4 eV is the optimal band alignment. 17,18 Outside this range, a negative CBO suffers from increasing interface recombination, while a large positive CBO forms a barrier that reduces photocurrent collection.…”

“…17,18 Outside this range, a negative CBO suffers from increasing interface recombination, while a large positive CBO forms a barrier that reduces photocurrent collection. Although numerous SnS solar cells with different buffer layers have been fabricated, band alignment studies have only been reported for CdS, 16,19 SnO 2 , 16 and ZnMgO. 20 Zinc oxysulfide (Zn(O,S)) is an excellent candidate for a wide band gap buffer layer because its constituent elements can be tuned to give any composition ranging between ZnO and ZnS, hence forming a favorable CBO with various absorber layers.…”