The Coupled Microfluidic Microbial Electrochemical Cell as a Self-powered Biohydrogen Generator

Aref Fadakar, Mohammad Mahdi Mardanpour1, Soheila Yaghmaei2

Department of Chemical and Petroleum Engineering, Sharif University of Technology, Azadi Avenue, P.O. Box 11365-9465, Tehran, Iran

Supplementary Materials

Hydrogen Gas Sensor Calibration

The rate of biohydrogen production in the microfluidic MEC was obtained using the

hydrogen gas sensor-MQ-8 and Arduino Uno R3 kit, which is appropriate for

measuring biohydrogen concentrations (less than 10000 ppm) in presence of other

gases. The hydrogen gas-sensor and the electronic kit are shown in Fig. S1.

1 Corresponding Author’s Tel.: +9821661664301E-mail address: mardanpour@ripi.ir (M. M. Mardanpour)2E-mail address: yaghmaei@sharif.edu (S. Yaghmaei)

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(A) (B)

(C)

Fig. S1. (A) The hydrogen gas sensor-MQ-8; (B) Arduino Uno R3 kit; (C) The experimental setup of microfluidic MXC in conjunction with hydrogen measurement

module.

The hydrogen gas sensor-MQ-8 was connected to the Arduino Uno R3 kit and the

laptop. This sensor was placed in the cathodic compartment of the MEC which has 1

ml volume. The Arduino software recorded the adsorbed hydrogen on the surface of

hydrogen gas sensor-MQ-8. To enhance the sensor precision, it was calibrated using

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the characterized hydrogen concentrations. The accurate concentrations of

hydrogen were injected into the cathodic compartment of the microfluidic MEC by

Hamilton Sample Lock syringe (1001SL, volume 1 ml). The recorded hydrogen

concentration has been drawn versus injected hydrogen concentration as the

calibration curve. The calibration curve is shown in Fig. S2.

0 200 400 600 800 1000 1200050

100150200250300350400450

The concentration of injected hydrogen into the compartment / ppm

Hydrogen

concentra

tion meas

ured by

MQ-8 sens

or / ppm

Fig. S2. The calibration curve of the hydrogen measurement module.

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