Exploring Novel Spintronic Responses From Advanced Functional Organic .

induced charge transfer states becomes stronger with the decreasing distance. This newphenomenon on one hand provides a unique way to magnetically control the photo-inducedcharge-transfer states. On the other hand, it predicts a method to optically tune the magneticplasmonic response. Consequently, this new finding affords a new approach to coupling theelectric, optic and magnetic properties for developing new metamaterials.Magneto-dielectric(a)1.0Spacing: 5nmSpacing:10nmSpacing: 20nm0.50.00300600900Magnetic field (mT)Fig. 5 (a) Magneto-dielectric property to show the coupling interaction between magnetizedcharge-transfer states and photo-induced charge transfer states. (b) Schematic for illustratingexcitons-based plasmonics with optical tuning.4. Discovery: Optically induced ferromagnetic properties from radical pairs [Scientificreports 5, 2015]We have discovered a new phenomenon that electrogenerated chemiluminescence canproduce a magnetic property after removing the applied magnetic field. Fig. 6 shows anabnormal magnetic field effect on electrogenerated chemiluminescence: the electrogeneratedchemiluminescence can still present a change even without a magnetic field. This unexpectedphenomenon suggests that the activated charge-transfer [Ru(bpy)33 TPrA ] complexes maybecome magnetized in magnetic field and experience a long magnetic relaxation after removingmagnetic field. Therefore, this new discovery presents a new way to manipulate the magneticproperty for developing new metamaterials.7DISTRIBUTION A: Distribution approved for public release

25Magnetic field (T)Normal MFEECL45Abnormal MFEECL302015MC1015 MC (%) MFEECL (%)a501.200.80.40.0050 100 150 200Time (s)Fig. 6 (a) Magnetic field effect on electrogenerated chemiluminescence and magnetocurrentshowing the magnetized charge-transfer states.5. Discovery: Optically induced magneto-optic properties from spin-exchange interactionin ferroelectrically semiconducting materials [Advanced Materials 27, 2899-2906, 2015We have found that the photoluminescence and photocurrent can be changed by theexternal magnetic field through changing the spin-exchange interaction in ferroelectricallysemiconducting perovskites. Fig. 7 indicates that the photoluminescence and photocurrent can bedecreased or increased under the external magnetic field. Consequently, the change ofphotocurrent and photoluminescence illustrates a new way to tune the optical and electricalproperties through tuning the spin-exchange interaction, leading to a breakthrough to createmagneto-optic functions in all functional materials.8DISTRIBUTION A: Distribution approved for public release

Signal change -photoluminescence0300 600 900Magnetic field (mT)Fig. 7 (a) Magnetic field effect on photocurrent and photoluminescence. (b)Diagram to show themechanism for magneto-optical effects in perovskites.9DISTRIBUTION A: Distribution approved for public release

II. Thin-film based polymer thermoelectric devicesThis research task has made the following six accomplishments including:1. New driving force of temperature-dependent surface polarization to cooperativelyenhance Seebeck effect and electrical conductivity in vertical multilayer organic thinfilm devices [ Phys. Chem. Chem. Phys. 16, 22201-22206, 2014]800-2Current Density (mA cm )-1Seebeck ( V K )We have explored a new mechanism to develop Seebeck effects by using temperaturedependent surface polarization based on vertical multi-layer thin-film devices(Al/P3HT:PCBM/Al, & Al/MoO3/P3HT:PCBM/Al). Here, the temperature-dependent surfacepolarization functions as an additional driving force, as compared with the traditional drivingforce from entropy difference, to diffuse the charge carriers under temperature differencetowards the development of Seebeck effects. We have demonstrate simultaneously enhancedSeebeck coefficient and electrical conductivity by using dielectric interface through thetemperature-dependent surface polarization to diffuse charge carriers in theAl/MoO3/P3HT:PCBM/Al thin-film device (Fig. 9). This temperature-dependent surfacepolarization provides a new mechanism allowing a co-operative relationship between Seebeckcoefficient and electrical oTemperature ( C) 0.9E-5 S m-11 (b)0.1Al/P3HT:PCBM/Al-1 1.4E-8 S m0.01Al/P3HT:PCBM/Al20010 Al/MoO /P3HT:PCBM/Al3800123Voltage (V)4Fig. 9 (a) Seebeck coefficients in dark condition. (b) Electric conduction in dark condition.2. Dual functions of Seebeck and cooling effects in organic thin-film devices [Submitted]Here we have explored the possibilities of using temperature-dependent surface polarizationas a new thermoelectric driving force to solve the conflicting requirement between electrical andthermal conductions in developing dual Seebeck and cooling effects based on the hybridorganic/inorganic Au/P(VDF-TrFE)/MoO3/ITO thin-film device (Fig. 10). On one hand, thetemperature-dependent surface polarization can lead to a temperature-dependent electrical field10DISTRIBUTION A: Distribution approved for public release

Au/P(VDF-TrFE)/MoO3/ITO1200 (a)800400Large Seebeck effect040506022.9oSeebeck ( V/K)1600Temperature ( C)to drift charge carriers from high to low-temperature surface, generating a large Seebeck effect.On the other hand, the temperature-dependent surface polarization can absorb heat at theAu/organic interface through charge-phonon coupling by thermionic injection mechanisms whenthe charge carriers are injected upon applying an electrical bias, leading to a cooling effect.Essentially, the temperature-dependent surface polarization provides a mechanism to developdual Seebeck and cooling effects through charge-phonon coupling based on thin-filmelectrode/organic/electrode devices.Au/P(VDF-TrFE)/MoO 3/ITO22.822.722.6ITO(b)Auo0.2 C cooling0.00 0.08 0.16 0.242Current density (mA/cm )70Temperature ( C)Fig. 10 (a) Seebeck coefficients. (b) Cooling effects with small injection currents.3. Seebeck effects in n-type and p-type polymers driven simultaneously by surfacepolarization and entropy differences based on conductor/polymer/conductor thin-filmdevices [ACS Nano, 9, 5208-5213, 2015]Here, we have reported a new approach of using intramolecular charge-transfer states todevelop Seebeck effects driven by both surface polarization difference and entropy difference inn-type and p-type conjugated polymers based on vertical conductor/polymer/conductor thin-filmdevices. We have obtained larger Seebeck coefficients when the charge-transfer states aregenerated by a white light illumination (Fig. 11). Simultaneously, the electrical conductivities areincreased from almost insulating state in dark condition to conducting state underphotoexcitation in both n-type IIDT and p-type IIDDT based devices. Furthermore, we find thatchanging electrical conductivity can switch the Seebeck effects between polarization and entropyregimes when the charge-transfer states are generated upon applying photoexcitation. Therefore,using intramolecular charge-transfer states presents an approach to develop thermoelectriceffects in organic materials-based vertical conductor/polymer/conductor thin-film devices.11DISTRIBUTION A: Distribution approved for public release

C8H17C8H170-3001400-2(b)100 mWcm12001000IIDDT800-250 mWcm600400Dark condition20030 40 50 60 o 70 80Temperature ( C)Dark condition50 mWcm-600100 mWcm-2O NN OC8H17C10H21C10H21O NC10H21SN OSS ( V/K)S ( V/K)300 (a)nIIDT-2-90030 40 50 60 o 70 80Temperature ( C)SnC8H17C10H21Fig. 11 Seebeck effects in n-type and p-type thin-film devices. (a) n-type ITO/IIDT/Au device.(b) p-type ITO/IIDDT/Au device.4. New mechanism to generate magneto-Seebeck effect by applying Hall effect on organicthin-film devices [Submitted]Hall effect can generate magneto-transport phenomenon in organic thin-film devices, andvertical organic thin-film devices can lead to large Seebeck effect. Therefore, combination ofHall effect and vertical organic thin-film devices can lead to a new mechanism to generatemagneto-Seebeck effect. Here we have discovered giant magnetic field effects on Seebeckcoefficients by applying Hall effect on vertical multi-layer ITO/PEDOT:PSS/Au thin-filmdevices (Fig. 12). This discovery demonstrates a magnetic approach to control the thermoelectricproperties in organic thin-film devices.700ITO(hot)/PEDOT:PSS(0.8 m)/Au(cold)50030010030S ( V/K)S ( V/K)680660Before M150mT300mT450mTAfter M64062050 70 90 o110 130Temperature( C)120 121 122 123 124125oTemperature( C)Fig. 12 Seebeck coefficient as a function of temperature under different magnetic field whenmagnetic field is perpendicular to temperature gradient.12DISTRIBUTION A: Distribution approved for public release

Personnel Supported:1. Ph.D student Mingxing Li with partial support2. Ph.D student Qing Liu with partial supportPublication preparation from April 2012 to March 31 20151.2.3.4.5.6.7.Magneto-Optical Studies on Spin-Dependent Charge Recombination and Dissociation inPerovskite Solar CellsYu-Che Hsiao, Ting Wu, Mingxing Li, and Bin HuAdv. Mater. 27. 2899, 2015Enhanced π–d Electron Coupling in the Excited State by Combining IntramolecularCharge-Transfer States with Surface-Modified Magnetic Nanoparticles in Organic–Magnetic NanocompositesMingxing Li, Min Wang, Lei He, Yu-Che Hsiao, Qing Liu, Hengxing Xu, Ting Wu, LiangYan, Loon-Seng Tan, Augustine Urbas, Long Y. Chiang and Bin HuAdv. Electron. Mater. DOI: 10.1002/aelm.201500058, 2015Abnormal Magnetic Field Effects on Electrogenerated ChemiluminescenceHaiping Pan, Yan Shen, Hongfeng Wang, Lei He, Bin HuScientific Report. 5, 9105, 2015Changing the sign of exchange interaction in radical pairs to tune magnetic field effect onelectrogenerated chemiluminescenceHaiping Pan, Yan Shen, Lin Luan, Kai Lu, Jiashun Duan, and Bin HuJ. Phys. Chem. C. 119, 8089, 2015Dynamic Coupling between Electrode Interface and Donor/Acceptor Interface via ChargeDissociation in Organic Solar Cells at Device-Operating ConditionTing Wu, Yu-Che Hsiao, Mingxing Li, Nam-Goo Kang, Jimmy W. Mays, Bin Hu*J. Phys. Chem. C. 119, 2727, 2015Seebeck Effects in N-Type and P-Type Polymers Driven Simultaneously by SurfacePolarization and Entropy Differences Based on Conductor/Polymer/Conductor Thin-FilmDevicesDehua Hu, Qing Liu, Jeremy Tisdale, Ting Lei, Jian Pei, Hsin Wang, Augustine Urbas, andBin HuACS Nano. 9, 5208, 2015Effects of a ferroelectric interface on thermionic injection-induced cooling in singleheterojunction devices based on thin-film electrode/medium/electrode designQing Liu, Ting Wu, Yu-Che Hsiao, Mingxing Li, Dehua Hu, Hongfeng Wang, HengxingXu, Jeremy Tisdale and Bin HuJ. Mater. Chem. A. 3, 14431, 201513DISTRIBUTION A: Distribution approved for public release

8.9.10.11.12.13.14.15.16.17.Optically tunable spin-exchange energy at donor:acceptor interfaces in organic solar cellsMingxing Li, Hongfeng Wang, Lei He, Huidong Zang, Hengxing Xu and Bin HuAppl. Phys. Lett. 105, 023302, 2014Optically-Tunable Magneto-Capacitance Phenomenon in Organic SemiconductingMaterials Developed by Electrical Polarization of Intermolecular Charge-Transfer StatesLei He, Mingxing Li, Augustine Urbas, and Bin HuAdv. Mater. 26, 3956, 2014Changing Line-Shape in Magnetic Field Effects through Interactions between ExcitedStates in Organic Semiconducting MaterialsLei He, Mingxing Li, Augustine Urbas, and Bin HuPhys. Rev. B. 89, 155304, 2014Optically tunable spin-exchange energy at donor:acceptor interfaces in organic solar cellsMingxing Li, Hongfeng Wang, Lei He, Huidong Zang, Hengxing Xu, and Bin HuAppl. Phys. Lett. 105, 023302, 2014Inter-triplet spin-spin interaction effects on inter-conversion between different spin states inintermediate triplet-triplet pairs towards singlet fissionXianfeng Qiao, Lin Luan, Yuchun Liu, Zhigang Yu, and Bin HuOrg. Electron. 15, 2168, 2014Magneto-Dielectric Effects Induced by Optically-Generated Intermolecular ChargeTransfer States in Organic Semiconducting MaterialsHuidong Zang, Liang Yan, Mingxing Li, Lei He, Zheng Gai, Ilia Ivanov, Min Wang, LongChiang, Augustine Urbas, and Bin HuScientific Report 3, 2812, 2013Spin Radicals Enhanced Magnetocapacitance Effect in Intermolecular Excited StatesHuidong Zang, Jianguo Wang, Mingxing Li, Lei He, Zitong Liu, Deqing Zhang, and BinHuJ. Phys. Chem. C. 117，14136-14140, 2013Enhancing Seebeck Effects by Using Excited States in Organic Semiconducting PolymerMEH-PPV Based on Multi-layer Electrode/Polymer/Electrode Thin-Film StructureLing Xu, Yuchun Liu, Matthew P.Garrett, Bingbing Chen, and Bin HuJ. Phys. Chem. C. 117, 10264, 2013Triplet-Charge Annihilation versus Triplet-Triplet Annihilation in Organic SemiconductorsMing Shao, Liang Yan, Li Mingxing, Ivanov Ilia, and Bin HuJ. Mater. Chem. C. 1, 1330, 2013High Seebeck Effects from Conducting Polymer: nate) Based Thin-Film Device with Hybrid Metal/Polymer/MetalArchitectureMichael Stanford, Hsin Wang, Ilia Ivanov, and Bin HuAppl. Phys. Lett. 101, 173304, 201214DISTRIBUTION A: Distribution approved for public release

Magnetocurrent of Charge-Polarizable C60-Diphenylaminofluorene Monoadduct-DerivedMagnetic NanocompositesLiang Yan, Min Wang, N.P. Raju, Arthur Epstein, Loon-Seng Tan, Augustine Urbas, LongY. Chiang, Bin HuJ. Am. Chem. Soc. 134, 3549-3554, 201219. Changing Inter-molecular Spin-Orbital Coupling for Generating Magnetic Field Effects inPhosphorescent Organic SemiconductorsLiang Yan, Ming Shao, Carlos F. O. Graeff, Ivo Hummelgen, Dongge Ma, Bin HuAppl. Phys. Lett. 100, 013301, 201218.Interactions and Transitions:a. Presentations at ConferencesInvited Presentation from July 01 2011 to December 31 2014(1)(2)(3)(4)(5)(6)(7)(8)Magneto-Optical Studies on Organic and Perovskite Solar CellsBin HuAsian Conference on Organic Electronics, National Cheng Kung University, Tainan,Taiwan, November 12-15, 2014Magneto-Dielectric Effects Generated by Charge-Transfer States in OrganicSemiconductorsBin Hu5th Topical Meeting on Spins in Organic Semiconductors, Himeji, Japan, October 1417, 2014New Magnetic Field Effects in Organic SemiconductorsBin Hu2014 International Symposium on Materials for Enabling Nanodevices, National ChengKung University, Tainan, Taiwan, September 03-06, 2014Magneto-optic properties in organic materialsBin HuAOARD conference on magnetic nanomaterials, University of Maryland, June 16-17,2014Organic spintronics, organic solar cells, and organic thermoelectricsBin HuE-MRS, Lille, France, May 26-30, 2014Magneto-optic properties in organic materialsBin HuUS-Taiwan Air Force Conference, Hualien, Taiwan, May 13-15, 2014Magneto-optic studies of photovoltaic processes at D:A interface and electrodeinterface in organic solar cellsBin HuIndo-US Joint Workshop on Organic Solar Cells, Kanpur, India, March 20-22, 2014Interface enhanced photovoltaic and Seebeck effects in organic solar cells andthermoelectric devices15DISTRIBUTION A: Distribution approved for public release

(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)Bin HuACS Annual Meeting, Dallas, TX, March 16, 2014Multiferroic Effects from Intermolecular Excited States in OrganicSemiconductorsBin HuBrazil-MRS meeting, Campos do Jordao, September 30 – October 04, 2013Magneto-Optic, Magneto-Electric, and Magneto-Thermoelectric Effects inOrganic SemiconductorsBin HuBES Program Review for the CNMS at Oak Ridge National Laboratory, September 2426, 2013Organic Thin-Film Thermoelectric DevicesBin HuFlexible Thermoelectric Workshop organized by AFOSR, Arlington, VA, July 09-10,2013Effects of Intermolecular and Dielectric-layer Interfaces on Internal PhotovoltaicProcesses in Organic Solar CellsBin HuIndo-US Joint Workshop on Organic Solar Cells, National Reviewable EnergyLaboratory, Golden, Co, June 24-25, 2013Magneto-optical Studies on Internal Photovoltaic Processes in Organic Solar CellsBin Hu2013 TechConnect World, National Innovation Summit and National SBIR Conference,Gaylord Hotel, National Harbor, Maryland, May 13-16, 2013Magneto-Dielectric Functions Developed by Intermolecular Excited StatesBin HuMRS Meetings, San Francisco, CA, April 01-05, 2013Departmental Seminar: Organic SpintronicsBin HuNational Taiwan University, Taipei, Taiwan, December 11, 2012Workshop on Organic SpintronicsBin HuIntermolecular Excited States-Based Organic SpintronicsNational Cheng Kung University, Tainan, Taiwan, December 06-07, 2012Effects of Intermolecular and Dielectric-layer Interfaces on Internal PhotovoltaicProcesses in Organic Solar CellsBin HuInternational Symposium on Organic and Dye-Sensitized Solar Cells 2012 (ISOPVDSC 2012), Taipei, Taiwan, November 24-29, 2012Electric-Magnetic Coupling in Organic SintronicsBin Hu9th National Conference on Organic Solids Electronics, Yangzhou, China, November10-12, 2012Magneto-optical studies on internal photovoltaic processes in organic solar cellsBin Hu16DISTRIBUTION A: Distribution approved for public release

(20)(21)(22)(23)(24)(25)(26)(27)(28)b.Workshop on key scientific and technological issues for development of nextgeneration organic solar cellsArlington, VA, September 20 – 21, 2012Multi-Ferroic Functions Developed by Inter-molecular Excited StatesBin Hu4th Topical Meeting on Spintronics in Organic Semiconductors, London, UK,September 10 – 14, 2012Excited States-Based Organic SpintronicsBin HuInternational Workshop on Novel Nano-Magnetic and Multifunctional Materials 2012Seoul, Korea, June 11-14, 2012Magneto-Optical Studies of Internal Photovoltaic Processes in Organic Solar CellsBin HuDepartmental seminar at Department of Materials Science and Engineering, Universityof Florida, Gainesville, FL, April 04, 2012Organic Molecular MetamaterialsBin HuOrganic Metamaterials Workshop, Army Research Laboratory, March 02, 2012Characterization and Understanding on Internal Photovoltaic Processes inOrganic Solar CellsBin HuInternational Photonics Conference – 2011, Tainan, Taiwan, December 07-08, 2011Organic Spintronics: Magnetic Field EffectsBin HuInternational Symposium on Organic Dye Sensitized Solar Cells, Tainan, Taiwan,December 08-10, 2011The Role of Inter-molecular Electron-Hole Pairs in Magnetic Field Effects inOrganic Materials,Bin Hu61st Annual Meeting of Japan Coordination Chemistry Society, Okayama, Japan,September 17-19, 2011Characterization and Understanding on Charge Dissociation, Transport,Collection in Organic

Enhanced electric-magnetic coupling from organic-magnetic nano-composite in excited state metamaterials [Advanced Electronic Materials . DOI: 10.1002/aelm.201500058]. We found that a stronger electric-magnetic coupling between charge-transfer states and spin dipoles in electric-magnetic nano-composite can be realized when exciting the nano .