Traps and Transport Resistance—The Next Frontier for Stable State-of-the-Art Non-Fullerene Acceptor Solar Cells

presented by Carsten Deibel at the MRS Spring Meeting 2022 on 12th May at 10:30 AM in Mid-Pacific Conference Center, Nautilus 1 & 2

Transcript

1. www.tu-chemnitz.de/physik/OPKM
   MRS Spring Meeting, Honolulu· 12. Mai 2022 · deibel@physik.tu-chemnitz.de
   Carsten Deibel
   
   
   Institut für Physik
   
   
   Technische Universität Chemnitz
   Traps and Transport Resistance:
   
   
   The Next Frontier for
   

   Non-Fullerene Acceptor Solar Cells
   Optik und Photonik kondensierter Materie
   
   
   
   
   
   
   
   
   
   
   
   
   

   View Slide

2. www.tu-chemnitz.de/physik/OPKM
   deibel@physik.tu-chemnitz.de
   How Do Organic Solar Cells Work?
   Step 1: light absorption
   
   
   ➟ exciton generation
   Voltage
   Current
   
   
   
   
   
   
   
   3
   

   View Slide

3. www.tu-chemnitz.de/physik/OPKM
   deibel@physik.tu-chemnitz.de
   How Do Organic Solar Cells Work?
   Step 2: exciton diffusion
   
   
   ➟ lost… but
   Voltage
   Current
   singlet losses
   
   
   
   
   
   
   
   4
   
   
   
   
   
   
   
   

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4. www.tu-chemnitz.de/physik/OPKM
   deibel@physik.tu-chemnitz.de
   How Do Organic Solar Cells Work?
   Step 2: exciton diffusion
   
   
   ➟ mostly reaches acceptor interface
   Voltage
   Current
   singlet losses
   
   
   
   
   
   
   
   5
   
   
   
   
   
   
   
   

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5. www.tu-chemnitz.de/physik/OPKM
   deibel@physik.tu-chemnitz.de
   How Do Organic Solar Cells Work?
   charge transfer:
   very fast and
   very ef
   fi
   cient
   Voltage
   Current
   singlet losses
   
   
   
   
   
   
   
   6
   Step 3: charge transfer
   
   
   ➟ charge transfer (CT) excitons
   

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6. www.tu-chemnitz.de/physik/OPKM
   deibel@physik.tu-chemnitz.de
   How Do Organic Solar Cells Work?
   Step 4: CT dissociation
   
   
   ➟ charge separated state
   Voltage
   Current
   singlet losses
   geminate losses
   
   
   
   
   
   
   
   7
   

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7. www.tu-chemnitz.de/physik/OPKM
   deibel@physik.tu-chemnitz.de
   How Do Organic Solar Cells Work?
   Step 5: nongeminate recombination
   
   
   ➟ major loss of photocurrent
   Voltage
   Current
   singlet losses
   geminate losses
   nongeminate losses
   
   
   
   
   
   
   
   8
   

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8. www.tu-chemnitz.de/physik/OPKM
   deibel@physik.tu-chemnitz.de
   How Do Organic Solar Cells Work?
   Step 6: charge extraction
   
   
   ➟ voltage loss due to
   

   transport resistance ∝ conductivity-1
   Voltage
   Current
   singlet losses
   geminate losses
   voltage loss
   
   
   
   
   
   
   
   9
   

   View Slide

9. www.tu-chemnitz.de/physik/OPKM
   MRS Spring Meeting, Honolulu· 12. Mai 2022 · deibel@physik.tu-chemnitz.de
   Authors
   PM6
   Y6
   Eva M. Herzig
   Rod MacKenzie
   Natalie Banerji
   Dietrich Zahn
   Christoph Brabec & 

   Ning Li
   Yana Vaynzof
   Christopher Wöpke
   Maria Saladina
   Clemens Göhler 

   (on the move to

   Kemerink group, Heidelberg)
   

   View Slide

10. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    Accelerated Aging
    11
    Devices
    Ag 150 nm
    MoOx 10 nm
    PM6:Y6 100/200 nm resp.
    ZnO 50 nm
    ITO 180 nm
    glass
    I cooperative project
    I aim: ageing mechanism
    I electrical characterisation reg.
    energy and recombination
    Christoph Brabec &
    

    Ning Li
    Devices made in the group of
    no encapsulation
    air&light
    N2&85°C
    In the following, I’ll focus on
    

    the FF losses
    

    by thermal degradation
    

    (dark, nitrogen, 85°C)
    

    View Slide

11. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    Impact of thermal degradation
    conditions: dark, nitrogen, 85°C for 24 or 96 h
    0 h
    96 h
    

    View Slide

12. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    Suns-Voc for (series) resistance-free j(V)
    ideal diode equation
    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
    j = j0
    ✓
    exp
    ✓
    q(V jRs)
    nkT
    ◆
    1
    ◆
    V jRs
    Rp
    jgen
    „realistic“ with series and shunt resistance
    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
    0 = j0
    ✓
    exp
    ✓
    q(Voc 0Rs)
    nkT
    ◆
    1
    ◆
    Voc 0Rs
    Rp
    jgen
    At open circuit, V=Voc, the current j(Voc) = 0 → (series) resistance
    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
    jgen = j0
    ✓
    exp
    ✓
    qVoc
    nkT
    ◆
    1
    ◆
    Voc
    Rp
    With suns-Voc method, the (series) resistance-free j(V) is reconstructed;
    contains all recombination
    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
    j = j0
    ✓
    exp
    ✓
    qV
    nkT
    ◆
    1
    ◆
    jgen
    

    View Slide

13. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    Recombination to explain FF losses?
    conditions: dark, nitrogen, 85°C for 24 or 96 h
    simulations by
    
    Rod MacKenzie
    

    View Slide

14. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    Recombination to explain FF losses?
    pseudo-FF from suns-Voc contains recombination FF losses & is unchanged!
    N2&85°C
    – NO!
    simulations by
    
    Rod MacKenzie
    

    View Slide

15. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    Drop between Applied and Internal Voltage!
    conditions: dark, nitrogen, 85°C for 24 or 96 h
    ΔV
    • thermal aging increases ΔV
    
    
    • voltage drop ΔV ∝ L
    

    (active layer thickness)
    
    
    • we also measured devices with
    

    L = 100 nm → ΔV ≈ 2x smaller
    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
    V = Vapplied(j, 1 sun) Voc(jsc, light intensity)
    

    View Slide

16. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    Voltage Loss by Transport Resistance
    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
    V = Vapplied Vinternal
    17
    Voltage
    Current
    voltage loss
    ΔV
    The poor scientist’s method to determine σ from ΔV(j)
    j(Vapplied)illum
    suns-Voc(Vinternal)
    Active layer
    
    
    - conductivity
    
    
    - thickness L
    
    
    - transport resistance Rtr
    AAADR3icjVJNS+RAEK2J36OrM3r0EhyEPQ0ZkV0vgviFF0HBGQVHlu7YxmbyRTozouIv2ev6Y/wJ/gpv4sGDr8tEdld2tUOnq19VvXqplExDbXLPu684Q8Mjo2PjE9XJqS/TM7X6bMck/cxXbT8Jk+xICqNCHat2rvNQHaWZEpEM1aHsbVj/4UBlRifxQX6ZqpNIBLE+077IAf2ozXSNDiLhrrqqG/VdIA2v6fFy3xutwmhQsfaSeqVGXTqlhHzqU0SKYsphhyTI4DmmFnmUAjuha2AZLM1+RTdURW4fUQoRAmgP7wC34wKNcbechrN9VAmxM2S6tIi9zYwS0baqgm1wPmNfMRb8s8I1M1uFlzglGCeYcRd4TueI+CgzKiJLLZ/JlMgq4yV/zSmsALoVnh7sUo/1Gdwv0C3L6oKzzPg95n8dzOmMVrhzGr1IGbE99d80bMKTcWXrcWmLIwNwSL4PUCPG2UY9+0dLBpe7a7ULPhWzxAWjAF/GurXVg5lq/T1B743OUrP1rbm8v9xYWy+ma5zmaYG+YoK+0xrt0B502Cn7Sb/o1rlzHpxH5+k11KkUOXP0xxqqvAAChqj+
    = eµn
    carrier mobility
    carrier concentration
    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
    =
    L
    2Rtr
    =
    jL
    2 V
    For background reading, see e.g. Würfel, Neher et al, Nature Comms (2015). DOI: 10.1038/ncomms7951
    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
    V =
    jL
    2
    

    View Slide

17. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    The internal voltage is not what you think it is
    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
    V =
    jL
    2
    AAADR3icjVJNS+RAEK2J36OrM3r0EhyEPQ0ZkV0vgviFF0HBGQVHlu7YxmbyRTozouIv2ev6Y/wJ/gpv4sGDr8tEdld2tUOnq19VvXqplExDbXLPu684Q8Mjo2PjE9XJqS/TM7X6bMck/cxXbT8Jk+xICqNCHat2rvNQHaWZEpEM1aHsbVj/4UBlRifxQX6ZqpNIBLE+077IAf2ozXSNDiLhrrqqG/VdIA2v6fFy3xutwmhQsfaSeqVGXTqlhHzqU0SKYsphhyTI4DmmFnmUAjuha2AZLM1+RTdURW4fUQoRAmgP7wC34wKNcbechrN9VAmxM2S6tIi9zYwS0baqgm1wPmNfMRb8s8I1M1uFlzglGCeYcRd4TueI+CgzKiJLLZ/JlMgq4yV/zSmsALoVnh7sUo/1Gdwv0C3L6oKzzPg95n8dzOmMVrhzGr1IGbE99d80bMKTcWXrcWmLIwNwSL4PUCPG2UY9+0dLBpe7a7ULPhWzxAWjAF/GurXVg5lq/T1B743OUrP1rbm8v9xYWy+ma5zmaYG+YoK+0xrt0B502Cn7Sb/o1rlzHpxH5+k11KkUOXP0xxqqvAAChqj+
    = eµn
    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
    j = f(n)
    artefact from ΔV
    

    for j ≈ jsc
    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
    V = Vapplied Vint
    Vapplied
    Vint
    

    View Slide

18. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    How does this loss „look“ like? (Band diagrams)
    simulations by
    
    Rod MacKenzie
    

    View Slide

19. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    Estimate of intrinsic carrier concentration from σ
    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
    V = Vapplied Vinternal
    20
    Intrinsic carrier concentration ni
    increases with thermal aging:
    
    
    trap formation!
    rier density ni
    . n is obtained from the chemi-
    tance Cµ
    (V ) = C(V ) geometric capacitance,
    equation35,36
    Voc
    ) = n (Vsat
    ) +
    1
    eL
    Z Voc
    Vsat
    Cµ
    (V ) dV . (3)
    voltage in the reverse-bias regime, where non-
    recombination is heavily suppressed. With
    e achieve an estimate for ni
    of the active layer
    ni
    = n (Voc
    ) exp
    ✓
    eVoc
    2kT
    ◆
    . (4)
    ing intrinsic carrier concentration ni
    , shown in
    creases from 1·1015 m 3 for the fresh device to
    015 m 3 after 96 h of aging (and ⇡ 1·1015 m 3
    015 m 3 for the 100 nm device). We interpret
    ase of ni
    as an indication for an aging-induced
    leads to increased n
    port resistance loss
    performance by a re
    and fill factor.
    I
    Materials. PM
    larmer Materials In
    electronic Materials
    zhen, China) and u
    (N10) were received
    Solar Cell Dev
    PM6:Y6 material s
    chitecture of glass/
    coated glass substr
    deionized water an
    tively. The ZnO na
    AAADW3icjVJNTxRBEK3dAYEVdNF48jJxY+JpM0uIciEhisaDJpC4CwlDSPfQO7Q7X+nuxeBmf4C/xqv+FA/+Ew++LmcMSBR70tPVVa9evakpWWXauij61moHC4u3lpZXOrdX1+7c7a7fG9lyahI1TMqsNIdSWJXpQg2ddpk6rIwSuczUgZy88PGDc2WsLot37qJSx7lICz3WiXBwnXR7sdVpLrbjsRHJ7P2b+Wwj3lWZE+Fovq3CIozzKVBRP+IVXjcGtdGjeu2V660uxXRKJSU0pZwUFeRgZyTI4jmiAUVUwXdMM/gMLM1xRXPqIHcKlAJCwDvBO8XtqPYWuHtOy9kJqmTYBpkhPcZ+xYwSaF9VwbY4f2B/ZF/61wozZvYKL3BKMK4w41v4HZ0BcVNmXiMbLf+TKZHV4CV/zSmsFLoVngnsRo+PWdw/oFueNQRnk3EZ868OOhrTFndOoxcVe3xPk98adhExXNlHQnrJyBQcku/nqFHgHKKe/6MNQ8jd9doFn4pZippRgM+wbu31YKYGf07QdWO00R887W/ub/Z2ntfTtUwP6RE9wQQ9ox16TXvQkdAn+kxf6Gv7exAEnWD1F7TdqnPu05UVPPgJ+9Oucg==
    =
    jL
    2 V
    = enµ
    The origin of ΔV:
    
    
    

    View Slide

20. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    Evidence for Trap Formation
    21
    Eva M. Herzig
    Impact of thermal aging:
    
    
    - PM6 π–π stacking in blend
    shows increased
    paracrystallinity disorder
    
    
    - increase in the amount of
    lamellar stacking
    
    
    Interpretation: lamellar stacking
    is enhanced at the cost of the
    π–π-stacking quality → traps
    

    View Slide

21. www.tu-chemnitz.de/physik/OPKM
    deibel@physik.tu-chemnitz.de
    FF Loss in thermally aged PM6:Y6 solar cells…
    22
    … is dominated by
    

    voltage loss due to transport
    resistance!
    
    
    Also important loss in
    
    
    - fresh devices
    

    - thin devices
    
    
    Origin: reduced conductivity
    

    due to trap formation
    

    in active layer
    
    
    preprint @ arXiv:2203.11905
    

    (quasi-accepted at NC;-)
    
    
    
    
    
    
    
    

    View Slide

22. www.tu-chemnitz.de/physik/OPKM
    MRS Spring Meeting, Honolulu· 12. Mai 2022 · deibel@physik.tu-chemnitz.de
    Acknowledgements
    23
    Thanks for having me!
    
    
    Thanks to my group and our partners!
    
    
    Thank you @ MRS Spring!
    

    View Slide