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We present a new ternary semiconductor sensitizer-AgBiS2 for solar cells. AgBiS2 nanoparticles were grown using a two-stage successive ionic layer adsorption and reaction process. Post annealing transformed the double-layered structure into AgBiS2 nanoparticles of 16 nm in diameter. Liquid-junction semiconductor-sensitized solar cells were fabricated from the synthesized AgBiS2 semiconductor. The best cell exhibited a short-circuit current density Jsc of 7.61 mA/cm2, an open-circuit voltage of 0.18 V, a fill factor of 38.6%, and a power conversion efficiency η of 0.53% under 1 sun. The η increased to 0.76% at a reduced light intensity of 0.148 sun. The external quantum efficiency (EQE) spectrum covered the spectral range of 350–850 nm, with an average EQE of 54% over the main spectral region of 450–650 nm. The Jsc under 0.148 sun was equal to 1.69 mA/cm2, a respectable Jsc for a new sensitizer

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 present a novel absorber material—NaSbS2—for solar cells. NaSbS2 is formed as an unexpected byproduct in the chemical synthesis of Sb2S3. However, NaSbS2 has many attractive features for a solar material. Here single phase NaSbS2 nanoparticles were synthesized through solution processing. NaSbS2 semiconductor-sensitized solar cells were demonstrated for the first time. The best cell yielded Jsc = 10.76 mA/cm2, Voc = 0.44 V, FF = 48.6%, and efficiency η = 2.30% under 1 sun. At the reduced 0.1 sun, the η increased to 3.18%—a respectable η for a new solar material.

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