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Lead iodide perovskite light-emitting field-effect transistor.

Chin XY, Cortecchia D, Yin J, Bruno A, Soci C - Nat Commun (2015)

Bottom Line: Here we show that screening effects associated to ionic transport can be effectively eliminated by lowering the operating temperature of methylammonium lead iodide perovskite (CH3NH3PbI3) field-effect transistors.Field-effect carrier mobility is found to increase by almost two orders of magnitude below 200 K, consistent with phonon scattering-limited transport.This demonstration of CH3NH3PbI3 light-emitting field-effect transistors provides intrinsic transport parameters to guide materials and solar cell optimization, and will drive the development of new electro-optic device concepts, such as gated light-emitting diodes and lasers operating at room temperature.

View Article: PubMed Central - PubMed

Affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.

ABSTRACT
Despite the widespread use of solution-processable hybrid organic-inorganic perovskites in photovoltaic and light-emitting applications, determination of their intrinsic charge transport parameters has been elusive due to the variability of film preparation and history-dependent device performance. Here we show that screening effects associated to ionic transport can be effectively eliminated by lowering the operating temperature of methylammonium lead iodide perovskite (CH3NH3PbI3) field-effect transistors. Field-effect carrier mobility is found to increase by almost two orders of magnitude below 200 K, consistent with phonon scattering-limited transport. Under balanced ambipolar carrier injection, gate-dependent electroluminescence is also observed from the transistor channel, with spectra revealing the tetragonal to orthorhombic phase transition. This demonstration of CH3NH3PbI3 light-emitting field-effect transistors provides intrinsic transport parameters to guide materials and solar cell optimization, and will drive the development of new electro-optic device concepts, such as gated light-emitting diodes and lasers operating at room temperature.

No MeSH data available.


Optical images of CH3NH3PbI3 LE-FET emission zone at T=158 K.(a–c) Frame images extracted from a video recorded while sweeping Vds from 0 to 100 V at constant Vgs=100 V; the corresponding values of Vds are indicated in the panels. (d–f) Frame images extracted from a video recorded while sweeping Vgs from 0 to 100 V at constant Vds=100 V; the corresponding values of Vgs are indicated in the panels; note that the contrast of the metal contacts was slightly enhanced for clarity. See Supplementary Movies 1 and 2 for the source real-time videos of the measurements. Scale bars, 200 μm.
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f5: Optical images of CH3NH3PbI3 LE-FET emission zone at T=158 K.(a–c) Frame images extracted from a video recorded while sweeping Vds from 0 to 100 V at constant Vgs=100 V; the corresponding values of Vds are indicated in the panels. (d–f) Frame images extracted from a video recorded while sweeping Vgs from 0 to 100 V at constant Vds=100 V; the corresponding values of Vgs are indicated in the panels; note that the contrast of the metal contacts was slightly enhanced for clarity. See Supplementary Movies 1 and 2 for the source real-time videos of the measurements. Scale bars, 200 μm.

Mentions: To achieve simultaneous hole and electron injection in a LE-FET, the local gate potential at drain and source electrodes must be larger than the threshold voltage of either of the charge carrier (that is, /Vd/>/Vth,h/ and Vs>Vth,e, or Vd>Vth,e and /Vs/>/Vth,h/)47. Under this condition, drain-source and gate voltages are tuned to control the injected current density of both carriers, which manipulate the spatial position of the emission zone as well as the EL intensity47. Figure 5 shows microscope images of the emission zone of the LE-FET recorded at 158 K under different biasing conditions. Despite the grainy light emission pattern due to the polycrystalline nature of the film (Fig. 1a,b), the EL emission zone can be clearly identified from the images. For a fixed gate bias of Vgs=100 V (Fig. 5a–c), the emission zone is mainly concentrated near the drain electrode when Vds is small (Fig. 5a). This is due to the limited injection of holes resulting from the relative low absolute local gate potential at the drain electrode /Vd/. By increasing Vds, /Vd/ increases, thus more holes are injected into the active channel and the EL intensity increases (Fig. 5b). Further increase of hole injection extends the emission area to the centre of the channel, enhancing the EL intensity even further (Fig. 5c). Conversely, for a fixed drain-source voltage of Vds=100 V (Fig. 5d–f), the injected electron and hole current densities can no longer be regulated independently. Figure 5d shows extremely bright emission from nearby the drain electrodes because of the overwhelming density of injected electrons recombining with a comparatively lower density of injected holes. Decreasing the gate voltage reduces the local gate potential at the source electrode Vs and increases /Vd/, thus decreasing electron injection and increasing hole injection. This pushes the emission zone to the centre of the active channel and reduces the EL intensity as overall current density decreases (Fig. 5e). A further reduction of gate voltage pushes the emission zone closer to the source electrode, further weakening the EL intensity (see Fig. 5f). Continuous-frame videos showing the variation of EL intensity and position of the emission zone sweeping Vds from 0 to 100 V at constant Vgs=100 V and sweeping Vgs from 0 to 100 V at constant Vds=100 V are provided as Supplementary Movies 1 and 2. This demonstrates that full control of charge carrier injection and recombination in CH3NH3PbI3 LE-FET can be easily achieved by adjusting its biasing conditions.


Lead iodide perovskite light-emitting field-effect transistor.

Chin XY, Cortecchia D, Yin J, Bruno A, Soci C - Nat Commun (2015)

Optical images of CH3NH3PbI3 LE-FET emission zone at T=158 K.(a–c) Frame images extracted from a video recorded while sweeping Vds from 0 to 100 V at constant Vgs=100 V; the corresponding values of Vds are indicated in the panels. (d–f) Frame images extracted from a video recorded while sweeping Vgs from 0 to 100 V at constant Vds=100 V; the corresponding values of Vgs are indicated in the panels; note that the contrast of the metal contacts was slightly enhanced for clarity. See Supplementary Movies 1 and 2 for the source real-time videos of the measurements. Scale bars, 200 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4491174&req=5

f5: Optical images of CH3NH3PbI3 LE-FET emission zone at T=158 K.(a–c) Frame images extracted from a video recorded while sweeping Vds from 0 to 100 V at constant Vgs=100 V; the corresponding values of Vds are indicated in the panels. (d–f) Frame images extracted from a video recorded while sweeping Vgs from 0 to 100 V at constant Vds=100 V; the corresponding values of Vgs are indicated in the panels; note that the contrast of the metal contacts was slightly enhanced for clarity. See Supplementary Movies 1 and 2 for the source real-time videos of the measurements. Scale bars, 200 μm.
Mentions: To achieve simultaneous hole and electron injection in a LE-FET, the local gate potential at drain and source electrodes must be larger than the threshold voltage of either of the charge carrier (that is, /Vd/>/Vth,h/ and Vs>Vth,e, or Vd>Vth,e and /Vs/>/Vth,h/)47. Under this condition, drain-source and gate voltages are tuned to control the injected current density of both carriers, which manipulate the spatial position of the emission zone as well as the EL intensity47. Figure 5 shows microscope images of the emission zone of the LE-FET recorded at 158 K under different biasing conditions. Despite the grainy light emission pattern due to the polycrystalline nature of the film (Fig. 1a,b), the EL emission zone can be clearly identified from the images. For a fixed gate bias of Vgs=100 V (Fig. 5a–c), the emission zone is mainly concentrated near the drain electrode when Vds is small (Fig. 5a). This is due to the limited injection of holes resulting from the relative low absolute local gate potential at the drain electrode /Vd/. By increasing Vds, /Vd/ increases, thus more holes are injected into the active channel and the EL intensity increases (Fig. 5b). Further increase of hole injection extends the emission area to the centre of the channel, enhancing the EL intensity even further (Fig. 5c). Conversely, for a fixed drain-source voltage of Vds=100 V (Fig. 5d–f), the injected electron and hole current densities can no longer be regulated independently. Figure 5d shows extremely bright emission from nearby the drain electrodes because of the overwhelming density of injected electrons recombining with a comparatively lower density of injected holes. Decreasing the gate voltage reduces the local gate potential at the source electrode Vs and increases /Vd/, thus decreasing electron injection and increasing hole injection. This pushes the emission zone to the centre of the active channel and reduces the EL intensity as overall current density decreases (Fig. 5e). A further reduction of gate voltage pushes the emission zone closer to the source electrode, further weakening the EL intensity (see Fig. 5f). Continuous-frame videos showing the variation of EL intensity and position of the emission zone sweeping Vds from 0 to 100 V at constant Vgs=100 V and sweeping Vgs from 0 to 100 V at constant Vds=100 V are provided as Supplementary Movies 1 and 2. This demonstrates that full control of charge carrier injection and recombination in CH3NH3PbI3 LE-FET can be easily achieved by adjusting its biasing conditions.

Bottom Line: Here we show that screening effects associated to ionic transport can be effectively eliminated by lowering the operating temperature of methylammonium lead iodide perovskite (CH3NH3PbI3) field-effect transistors.Field-effect carrier mobility is found to increase by almost two orders of magnitude below 200 K, consistent with phonon scattering-limited transport.This demonstration of CH3NH3PbI3 light-emitting field-effect transistors provides intrinsic transport parameters to guide materials and solar cell optimization, and will drive the development of new electro-optic device concepts, such as gated light-emitting diodes and lasers operating at room temperature.

View Article: PubMed Central - PubMed

Affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.

ABSTRACT
Despite the widespread use of solution-processable hybrid organic-inorganic perovskites in photovoltaic and light-emitting applications, determination of their intrinsic charge transport parameters has been elusive due to the variability of film preparation and history-dependent device performance. Here we show that screening effects associated to ionic transport can be effectively eliminated by lowering the operating temperature of methylammonium lead iodide perovskite (CH3NH3PbI3) field-effect transistors. Field-effect carrier mobility is found to increase by almost two orders of magnitude below 200 K, consistent with phonon scattering-limited transport. Under balanced ambipolar carrier injection, gate-dependent electroluminescence is also observed from the transistor channel, with spectra revealing the tetragonal to orthorhombic phase transition. This demonstration of CH3NH3PbI3 light-emitting field-effect transistors provides intrinsic transport parameters to guide materials and solar cell optimization, and will drive the development of new electro-optic device concepts, such as gated light-emitting diodes and lasers operating at room temperature.

No MeSH data available.