# US 2014/0196778 A1 · Light absorbing material and solar cell including the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0196778 A1 - Document ID: US20140196778A1 - Status: Published application - Kind: A1 - Application number: 14/152,325 - Filed: 2014-01-10 - Published: 2014-07-17 - Earliest claimed: 2013-01-14 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Jin Wook LEE - Web page: https://patentgrep.com/patent/US20140196778A1 ## CPC - H10F 77/1433: {Quantum dots} - H10F 10/19: Photovoltaic cells having multiple potential barriers of different types, e.g. tandem cells having both PN and PIN junctions - H10F 77/12: Active materials - H10K 30/50: Photovoltaic [PV] devices - H10K 85/1135: {Polyethylene dioxythiophene [PEDOT]; Derivatives thereof} - Y02E 10/549: Organic PV cells - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A light absorbing material may have an energy bandgap of greater than or equal to about 0.8 eV and an absorption coefficient of greater than about 2.1×105 cm−1 at about 0.8 eV. ## Claims ### Claim 1 A light absorbing material having an energy bandgap of greater than or equal to about 0.8 eV and an absorption coefficient of greater than about 2.1×105 cm−1 at about 0.8 eV. ### Claim 2 (depends on 1) The light absorbing material of claim 1, wherein the light absorbing material is at least one material selected from RhSb3, CeN, SnTe, LaSb, CoSb3, ZnSnSb2, CsBi2, Cu3SbSe4, MnSi, Cu2SnSe3, Cu3SbS4, SmSb, CoO, Li3P, TISe, PrSb, and PtS. ### Claim 3 (depends on 1) The light absorbing material of claim 1, wherein the light absorbing material is a semiconductor crystal having a particle radius of about 2 nm to about 500 nm, and the energy bandgap of the light absorbing material varies depending on the particle radius. ### Claim 4 A solar cell, comprising: a first electrode and a second electrode facing each other; and at least one photoactive layer between the first electrode and the second electrode, the at least one photoactive layer including a light absorbing material having an energy bandgap of greater than or equal to about 0.8 eV and an absorption coefficient of greater than about 2.1×105 cm−1 at about 0.8 eV. ### Claim 5 (depends on 4) The solar cell of claim 4, wherein the light absorbing material is at least one material selected from RhSb3, CeN, SnTe, LaSb, CoSb3, ZnSnSb2, CsBi2, Cu3SbSe4, MnSi, Cu2SnSe3, Cu3SbS4, SmSb, CoO, Li3P, TISe, PrSb, and PtS. ### Claim 6 (depends on 4) The solar cell of claim 4, wherein the light absorbing material is a semiconductor crystal having a particle radius of about 2 nm to about 500 nm. ### Claim 7 (depends on 4) The solar cell of claim 4, further comprising: an auxiliary layer between at least one of the first electrode and the at least one photoactive layer, and the second electrode and the at least one photoactive layer. ### Claim 8 (depends on 4) The solar cell of claim 4, wherein the at least one photoactive layer has a tandem structure including at least two stacked photoactive layers. ### Claim 9 (depends on 8) The solar cell of claim 8, wherein the at least one photoactive layer includes a first photoactive layer and a second photoactive layer including light absorbing materials having different particle radii from each other. ### Claim 10 (depends on 9) The solar cell of claim 9, wherein the first photoactive layer includes a light absorbing material having a first particle radius, the second photoactive layer includes the light absorbing material having a second particle radius, the second particle radius larger than the first particle radius, and the first photoactive layer absorbs light having a shorter wavelength range than the second photoactive layer. ### Claim 11 (depends on 9) The solar cell of claim 9, further comprising: an interconnecting layer between the first photoactive layer and the second photoactive layer. ### Claim 12 (depends on 8) The solar cell of claim 8, wherein the at least one photoactive layer includes a first photoactive layer, a second photoactive layer, and a third photoactive layer including light absorbing materials having different particle radii from each other. ### Claim 13 (depends on 12) The solar cell of claim 12, wherein the first photoactive layer includes a light absorbing material having a particle radius showing an energy bandgap of about 2.1 eV to about 2.5 eV, the second photoactive layer includes a light absorbing material having a particle radius showing an energy bandgap of about 1.2 eV to about 1.6 eV, and the third photoactive layer includes a light absorbing material having a particle radius showing an energy bandgap of about 0.8 eV to about 1.0 eV. ### Claim 14 (depends on 12) The solar cell of claim 12, wherein the first photoactive layer includes a light absorbing material having a first particle radius, the second photoactive layer includes a light absorbing material having a second particle radius, the second particle radius larger than the first particle radius, the third photoactive layer includes a light absorbing material having a third particle radius, the third particle radius larger than the second particle radius, and the first photoactive layer, the second photoactive layer, and the third photoactive layer absorb light having a first wavelength range, a second wavelength range longer than the first wavelength range, and a third wavelength range longer than the first and second wavelength ranges, respectively. ### Claim 15 (depends on 14) The solar cell of claim 14, wherein the first particle radius ranges from about 2 nm to about 20 nm, the second particle radius ranges from about 3 nm to about 50 nm, and the third particle radius ranges from about 6 nm to about 300 nm. ### Claim 16 (depends on 14) The solar cell of claim 14, wherein the first wavelength range is less than or equal to about 590 nm, the second wavelength range is from about 591 nm to about 1033 nm, and the third wavelength range is from about 1034 nm to about 2066 nm. ### Claim 17 (depends on 12) The solar cell of claim 12, further comprising: at least one interconnecting layer between the first photoactive layer and the second photoactive layer, and between the second photoactive layer and the third photoactive layer. ### Claim 18 A solar cell comprising: a first electrode and a second electrode facing each other; and at least one photoactive layer between the first electrode and the second electrode, the at least one photoactive layer including a light absorbing material having a particle radius of about 2 nm to 500 nm, wherein the light absorbing material is at least one material selected from RhSb3, CeN, SnTe, LaSb, CoSb3, ZnSnSb2, CsBi2, Cu3SbSe4, MnSi, Cu2SnSe3, Cu3SbS4, SmSb, CoO, Li3P, TISe, PrSb, and PtS. ### Claim 19 (depends on 18) The solar cell of claim 18, wherein the at least one photoactive layer includes a first photoactive layer, a second photoactive layer, and a third photoactive layer including light absorbing materials having different particle radii from each other. ### Claim 20 (depends on 19) The solar cell of claim 19, wherein the first photoactive layer includes a light absorbing material having a particle radius of about 2 nm to about 20 nm, the second photoactive layer includes a light absorbing material having a particle radius of about 3 nm to about 50 nm, and the third photoactive layer includes a light absorbing material having a particle radius of about 6 nm to about 300 nm.