Effect of band occupations in intermediate-band solar cells

The Important Role of Optical Absorption in Determining the Efficiency of Intermediate Band Solar Cells and a Design Principle for Perovskite Doping

“…Since the concept of an IB solar cell was proposed, many attempts have been made to introduce IB in large-gap semiconductors. − In the field of perovskites, doping is found to be an effective way to introduce IB. − The introduced IB should be half-filled to reach a high efficiency . In addition, considering nonradiative recombination, − the IB should also have a notable dispersion to be spatially delocalized, which reduces the structure relaxation and suppresses the lattice relaxation multiphonon emission mechanism of nonradiative recombination. − In a previous study of inorganic perovskite (ABX 3 ) doping, we find that (In, Ga) doped CsPbCl 3 has a stable half-filled IB.…”

“…The IBs of Ge-doped Cs 2 AgBiCl 6 and Sn-doped Cs 2 AgBiX 6 (X = Cl, Br) are completely separated from valence bands (VBs) and conduction bands (CBs). They also have notable dispersion and are half-filled (Figure a–c), which makes them desirable for constructing IB solar cells. ,, Test calculations with PBE at smaller doping concentrations suggest that the half-filling property is robust and not sensitive to symmetry of local chemical environment (Figure S4). The IB-VB and CB-IB gaps are also not very sensitive to the doping concentrations (Table S2).…”