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PSL-100 Electron Lifetime & Diffusion Measurement System

PSL-100 Electron Lifetime & Diffusion Measurement System


  • Electron Lifetime・Electron Diffusion・Electron Density・I-V Curve measurement
  • Advanced system for DSC evaluation
  • For material development of DSC cells
  • Laser operated 660nm / 473nm

Traditionally Dye-Sensitized Solar Cell (DSC) materials could only be tested by measuring the electrical performance of assembled solar cells. However in order to improve the conversion rate of the solar cells, it is necessary to improve short circuit current (Isc) and open circuit voltage (Voc). Therefore for DSC, it is very important to understand the characteristics of the electron transfer inside the cell, which significantly contribute to the performance of the cell.

With the PSL-100 Electron life time tester, the electron transfer process inside the DSC porous electrode can be determined and will give a more detailed guideline for material development and cell efficiency improvement.

The Electron Lifetime & Diffusion Measurement System “PSL-100” measures electron transfer characteristics, “Electron Diffusion Coefficient (D)” and “Electron Lifetime (τ)” for sample size level DSC based on the measurement theory of SLIM-PCV(Stepped Light-induced Transient Measurements of Photocurrent and Voltage method.

Electron Diffusion Length

"Electron Diffusion Length" is defined as the distance of transferring electron which is excited by light irradiance till it gets recombined. In other words, if this distance is shorter than the thickness of the DSC porous semiconductor electrode, all by light excited electrons cannot be extracted. So the Electron Diffusion Length(L) can be expressed as following by using Electron Diffusion Coefficient (D)and Electron Lifetime (τ):



Electron Diffusion Coefficient

Electron Lifetime

Measure the easiness of electron transfer inside the DSC porous electrode.

Measure the time till the electron, which injected inside the DSC porous electrode, is recombined with dye or electrolytes(I3-).

Light intensity drops, the slow voltage response.

In other word, the long Electron Lifetime.

PSL-100_ps01 PSL-100_ps02

Electron Density

Measure the electron density from the electron which is photoexcited inside the DSSC.  

PSL-100 Data Analysis Graph

Correlative Graph of

Electron Diffusion Coefficient


Short-Circuit Current Density

Correlative Graph of

Electron Lifetime


Short-Circuit Current Density
PSL-100_g01 PSL-100_g02

Correlative Graph of

Electron Density


Electron Lifetime

Correlative Graph of

Electron Density


Open-Circuit Voltage
PSL-100_g03 PSL-100_g04

Option for Excited Light Source Wavelength

In recent years, all kinds of dyes are applied in the research and development, and needs for excited light source wavelength used in the measurements have become diverse.

In order to satisfy these needs, PLS-100 naw has optional “473nm wavelength laser” for shorter wavelength range, addition to the standard “660nm wavelength laser”.

For the cells which excitation at the wavelength range of 660nm was unstable and had given up on the measurements, please try this optional laser.


The graphs show the examples of DSC cell measurement result of dyes, which have absorption to both “660nm” and “473nm” excited wavelength range, is absorbed to TiO₂ electrodes.

When the absorption of semiconductor electrode is small, the electron transfer characteristics are the same by either light source is used for the measurement. This indicates that relative comparison evaluation can be done by same excited density (electron density) even between the different excited light source wavelength.

PSL100-Fig.08  PSL100-Fig.09

Data Provided by : Shinshu University, Faculty of Textile Science and Technology, Mori Laboratory


Installation Condition Indoor use only
Operating Temperature +10℃ ~ +40℃
Humidity Less than 70% (no condensation)

Measurement Unit PSL-100-M

General Specification
Power Supply AC 100[V] ±10%
Frequency Range 50[Hz]/60[Hz]
Power Consumption Less than 25[VA]
Warm-up Time More than 30 minutes
Outer Dimensions 480(W)×190(H)×350(D)[mm]
※Without Handle and Rubber Legs
Weight 10[kg]
Measurement Part Specification
Electron Diffusion Coefficients Measurement  
Measurement Method Current measurement (Current/Voltage Conversation)
Conversion Ratio 1.0000[mA] / 1.0000[V]
Measurable Rabge -0.3000[mA] ~ +1.2000[mA]
A/D Conversion Rate 1:1
Value Data Rate ±0.005[mA]
Electron Lifetime Measurement  
Measurement Method Voltage measurement
Input Impedance More than 109[Ω]
Measurable Range -0.3000[V] ~ +1.2000[V]
A/D Conversion Rate 1:1
Value Data Error Within ±0.005[V]
Electron Density Measurement  
I-V Curve Measurement  
I-V Curve Measurement  
Control Method Bias Potential Applied Method
Control Output Impedance Less than 20[Ω]
Control Output Setup Range -0.3000[V] ~ +1.2000[V]
Control Output Setup Resolution 0.0001[V]
Control Output Setup Error ±0.005[V]
Voltage Measurement Unit  
Measurement Method Voltage measurement
Input Impedance More than 109[Ω]
Voltage measurement conversion ratio 1:1
Voltage Measurable Range -0.3000[V] ~ +1.2000[V]
A/D Conversion Rate 1:1
Value Data Error Within ±0.005[V]
Current Measurement Unit  
Measurement Method Current measurement (Current/Voltage Conversion)
Measurable Range 4 ranges(100mA,10mA,1mA,100μA)
Conversion Ratio Current Ranges F.S. / 1.0000[V]
Measurable Ranges 100mA Range :-30.000[mA]~+100.00[mA]
10mA Range:-3.0000[mA]~+10.000[mA]
1mA Range:-0.3000[mA]~+1.0000[mA]
100μA Range:-30.000[μA]~+100.00[μA]
A/D Conversion Rate 1:1
Value Data Error 100mA Range:Within ±1.0[mA]
10mA Range :Within ±0.05[mA]
1mA Range : Within ±0.005[mA]
100μA Range: Within ±0.5[μA]
 Communication Specification
Communication Method Serial Communication Method
Communication Port

USB port or RS-232C Port

※Recommend to use USB Port

Communication Speed 19200bps

Optical Bench PSL-100-O

General Specification
Outer Dimensions 803(W)×290(H)×303(D)[mm]
※Without Rubber Legs
Weight 50[kg]
Optical Parts (Main Parts)
Laser Specification (Standard Light Source)  
Laser Used MLX-D12-640-40 By Kiko
Safety Class 3B
Optical Lens φ6.4 Aspheric Glass Lens
Laser Light Wavelength 660[nm] ±10[nm]
Plano-Convex Lens Specification  
Lens                         SLB-30-60P By Sigma Koki
Outer Dimension φ30[mm] +0~-0.1[mm]
Focal Point Distance 60[mm] ±1%

Laser Operation Unit PSL-100-L

General Specification
Outer Dimensions

※Without Rubber Legs

Weight 3.0[kg]
Power Supply AC100V ±10% or AC200V ±10%
Frequency Range 50Hz / 60Hz
Power Consumption Less than 6.3VA
Warm-up Time More than 30 minutes

Software PSL-100

Operating Environment
OS MS Windows 7 
HHD Capacity Approx. 10GB
Memory More than 2GB
Display Resolution 1280×1024 pixel
Interface More than 2 USB ports
Measurement Items Electron Diffusion Coefficients (D) Measurement
Electron Lifetime (τ) Measurement
Electron Density (n) Measurement
I-V Curve Measurement
Data Analysis Creating data table 
Drawing Analysis Plot Chart 

Short-Circuit Current Density vs. Electron Diffusion Coefficients Measurement

Short-Circuit Current Density vs. Electron Lifetime

Electron Density vs. Electron Lifetime

Electron Density vs. Open-Circuit Voltage