Dielectric screening plays an important role in reducing the strength of carrier scattering and trapping by point defects for many semiconductors such as the halide perovskite solar materials. However, it was rarely considered as a screen to find new electronic semiconductors. We performed a material search study using the dielectric properties as a screen to identify potential electronic materials in the class of metal-pnictide ternary sulfosalts, containing Bi or Sb. These salts are basically ionic due to the electronegativity difference between the S and both the metal and pnictogen elements. However, we do find significant cross-gap hybridization between the S pderived valence bands and pnictogen p-derived conduction bands in many of the materials. This leads to enhanced Born effective charges, and in several cases, highly enhanced dielectric constants. We find a chemical rule for high dielectric constants in terms of the bond connectivity of the pnictogen-chalcogen part of the crystal structure.We additionally find a series of compounds with low effective mass, high dielectric constant and other properties that suggest good performance as electronic materials and also several potential thermoelectric compounds. Experimental optical data and solar conversion efficiency are reported for Sn-Sb-S samples, and results in accord with predicted good performance are found. The results illustrate the utility of dielectric properties as a screen for identifying complex semiconductors. (63) Kim, J. H.; Chung, D. Y.; Bilc, D.; Loo, S.; Short, J.; Mahanti, S. D.; Hogan, T.; Kanatzidis, M. G. Crystal Growth, Thermoelectric Properties, and Electronic Structure of AgBi 3 S 5 and AgSb x Bi 3-X S 5 (X=0.3). Chem. Mat. 2005, 17 (14), 3606-3614. (64) Parker, D.; May, A. F.; Wang, H.; McGuire, M. A.; Sales, B. C.; Singh, D. J. Electronic and

We report the synthesis and photovoltaic properties of a new ternary solar absorber – Ag8SnS6 nanocrystals prepared by successive ionic layer adsorption reaction (SILAR) technique.

This work investigates the synthesis of a new ternary alloyed metal sulfide semiconductor Sn x Sb2–y S3 and its application in solar cells. Sn x Sb2–y S3 nanocrystals were synthesized by incorporating Sn2+ ions into the host binary Sb2S3 semiconductor using a two-step sequential ionic layer adsorption reaction (SILAR) process. The ternary Sn x Sb2–y S3 semiconductor maintains the monoclinic crystalline structure of the binary Sb2S3 host with a small expansion in lattice constants relative to that of Sb2S3. Energy-dispersive X-ray analysis revealed the nominal chemical composition of the sample with eight SILAR cycles to be Sn0.52Sb1.48S3. The energy gap E g of Sn x Sb2–y S3 decreases with increasing Sn content x, resulting in a tunable E g from 620 to 800 nm (i.e., 2.0–1.5 eV) for x = 0–0.56. Liquid-junction quantum dot-sensitized solar cells were fabricated, for the first time, from the prepared Sn x Sb2–y S3 nanocrystals using the polyiodide electrolyte. The best cell yielded an efficiency of 2.58% with the photovoltaic parameters of J sc = 14.04 mA/cm2, V oc = 0.46 V, and FF = 39.9% under 1 sun. The efficiency improved to a respectable value of 4.89% under the reduced light intensity of 0.05%. The external quantum efficiency (EQE) spectrum has a maximal EQE of 71.8% at λ = 500 nm and covers the spectral range of 300–800 nm, which is significantly broader than that (300–620 nm) of the host Sb2S3. The broader optical absorption band increases light harvesting and results in a J sc ≈ 64% larger than that of the host Sb2S3. The result demonstrates the tunable optical properties of Sn x Sb2–y S3 by controlling the cationic Sn and Sb compositions, which is a favorable property for a solar absorber.

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We report the synthesis and photovoltaic properties of a ternary metal sulfide alloyed semiconductor PbxCd1−xS prepared by the two‐stage sequential ionic layer adsorption reaction. The synthesized PbxCd1−xS nanoparticles (NPs) retain the hexagonal structure of the CdS host with Pb substituting a fraction of the Cd atom (x = 0‐0.17). Band structures of PbxCd1−xS with various Pb contents x were calculated using the complementary density functional theory (DFT) method. Optical, quantum efficiency, cyclic voltammetry measurements, and band structure calculation revealed that the band gap of PbxCd1−xS decreased with increasing x, resulting in an increased optical absorption band from 500 to 720 nm (1.73‐2.44 eV) for x = 0 to 0.17. Solid‐state PbxCd1−xS semiconductor nanoparticle‐sensitized solar cells (NSSCs) were fabricated from the synthesized NPs using spiro‐OMeTAD as the hole‐transporting material. The best Pb0.05Cd0.95S cell yielded a power conversion efficiency (PCE) of 3.67%, a Voc of 0.70 V, and a fill factor (FF) of 62.8% under 1 sun. The PCE increased to 5.93% under a reduced light intensity of 0.1 sun and further increased to 8.48% under 0.01 sun. The external quantum efficiency (EQE) spectrum covers the spectral range of 300 to 730 nm with a maximal EQE of 82% at λ = 580 nm. The PCE over 8% can be categorized into a high‐efficiency NSSCs. In addition, the Voc of 0.70 V is a relatively high Voc among all NSSCs. The high PCE and Voc suggest that PbxCd1−xS has potential to be an efficient solar absorber.

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