H2 Microsensor for hydrogen research

Designed for research applications within:

Environmental Sciences

Biomedical Sciences

Biotechnology

Photoelectrochemical water splitting

Effect of H₂ enriched drinking water

Power-to-X

H₂ Microsensor

Highly sensitive hydrogen microsensor for gas and liquid measurements

The hydrogen microsensor offers you extraordinary sensitivity for reliable hydrogen measurement, even in natural systems and in gas. You will get a fast responding sensor, and you can choose a tip size down to 10 µm to achieve high spatial resolution. Read more...

Manuals

H₂ Microsensor Manual (PDF)

H₂ Microsensor Manual – before Sep 28, 2020 (PDF)

Technical Data

Stirring Sensitivity & Response Time

Ordering Information & Sizes

Customizations

Manuals & Videos

Quick Enquiry

H₂ Microsensor

Measure H₂ without H₂S interference

H₂S interferes with your H₂ measurements. For that reason, you can choose between two types of hydrogen microsensors.

If you are measuring in an H₂S free environment, you can choose the standard type, H₂.
If you want to measure in environments containing H₂S, you should use the H₂-X instead. This sensor has an H₂S guard in the sensor tip that makes it insensitive to H₂S; up to 100 µM H₂S or 1,000 ppm H₂S in gas.

We can also make you a sensor with an even higher tolerance to H₂S. Contact us for more information.

Manuals & Videos

Two types of hydrogen sensors

You can use the two types of hydrogen sensors, H₂ and H₂-X, in the same way. The only differences between the two sensor types are that the H₂-X tolerates H₂S and has a slightly slower response.

The H₂ and H₂-X microsensors are Clark-type sensors measuring hydrogen partial pressure.

The working principle of the hydrogen microsensor is based on diffusion of hydrogen through a silicone rubber membrane in the tip to a platinum anode where the hydrogen gets oxidized. This anode is polarized against an internal reference electrode which receives the electrons from the oxidation of hydrogen at the platinum anode.

The resulting current changes linearly with the hydrogen concentration at the sensor tip and is in the pA range. It is measured by a high quality picoammeter, such as the UniAmp amplifiers.

As hydrogen concentrations found in natural systems are generally very low, a low detection limit of the sensor is important.

Generally, the detection limit of the sensors is close to 0.04% of hydrogen (0.3 µM in water) but with a larger tip membrane we can make the sensors even more sensitive, except for those with 10 µm and 25 µm tip diameter. Such low range sensors are more sensitive to stirring due to the larger analyte consumption rate.

The H₂ sensor can even be produced with an extreme sensitivity with a detection limit lower than 10 nM dissolved (approx. 0.00125%) H₂. And as for all Unisense sensors, we can also make the H₂ sensors for much higher H₂ concentrations in pressurized systems.

H₂

H₂-X

General

Cables & Connectors

Characteristics

General

Feature	Standard	Options	Extra price for option selection
Feature Total length	Standard 150-200 mm	Options 70-350 mm	Extra price for option selection 20-50%
Feature Diameter 20 mm from tip	Standard < 2 mm	Options < 1 mm	Extra price for option selection 10%
Feature Glass shaft diameter	Standard 8 mm
Feature Plastic shaft protection diameter*	Standard 11 mm	Options Can be omitted	Extra price for option selection

*When mounted with in situ mini connectors, the shaft has no protection mounted, but fits directly into the in situ sensor mounts with pressure compensation. In situ sensors have a standard length of 140 mm ± 5 mm.

Cables & Connectors

Item	Standard	Options	Extra price for option selection
Item Cable	Standard Habia
Item Cable length	Standard 1.5-2 m	Options 0-10 m	Extra price for option selection Yes, depends on length
Item Connector	Standard LEMO	Options BNC adaptor	Extra price for option selection Yes, order separately
Item In situ gold pin connector*	Standard No	Options Yes

Characteristics

Attribute	Standard	Options	Extra price for option selection
Attribute Guaranteed lifetime	Standard 3 months
Attribute Expected lifetime	Standard > 1 Year
Attribute Temperature range	Standard 0-60°C
Attribute Temperature coefficient	Standard 2-3% per °C
Attribute Range	Standard 0-2,000 µM dissolved H₂ (0-250% H₂)	Options High Range >2,000 µM	Extra price for option selection 20%
Attribute Low Range sensors (LR)	Standard 0-80 µM (approx. 0-10% H₂)
Attribute Detection limit	Standard 0.3 µM in water	Options < 50 nM (only for tip sizes ≥ 50 µm)	Extra price for option selection 10%
Attribute Internal reference	Standard Yes
Attribute Waterproof	Standard Yes
Attribute Spatial resolution	Standard Equals outside tip diameter
Attribute Response	Standard Linear
Attribute Known interferences	Standard Reduced volatile sulfur-containing substances, like H₂S interfere strongly. Should not be used in anaerobic biological systems containing H₂S (use H₂-X instead).

General

Cables & Connectors

Characteristics

General

Feature	Standard	Options	Extra price for option selection
Feature Total length	Standard 150-200 mm	Options 70-350 mm	Extra price for option selection 20-50%
Feature Diameter 20 mm from tip	Standard < 4 mm
Feature Glass shaft diameter	Standard 8 mm
Feature Plastic shaft protection diameter*	Standard 11 mm	Options Can be omitted	Extra price for option selection

Cables & Connectors

Item	Standard	Options	Extra price for option selection
Item Cable	Standard Habia
Item Cable length	Standard 1.5-2 m	Options 0-10 m	Extra price for option selection Yes, depends on length
Item Connector	Standard LEMO	Options BNC adaptor	Extra price for option selection Yes, order separately
Item In situ gold pin connector*	Standard No	Options Yes

Characteristics

Attribute	Standard	Options	Extra price for option selection
Attribute Guaranteed lifetime	Standard 3 months
Attribute Expected lifetime	Standard > 6 months
Attribute Temperature range	Standard 0-50°C
Attribute Temperature coefficient	Standard 2-3% per °C
Attribute Range	Standard 0-2,000 µM dissolved H₂ (0-250% H₂)	Options High Range >2,000 µM	Extra price for option selection 20%
Attribute Low Range sensors (LR)	Standard 0-80 µM (approx. 0-10% H₂)
Attribute Detection limit	Standard 0.3 µM dissolved H₂ (approx. 0.0375% H₂)	Options Low Range sensors (LR): < 50 nM dissolved H₂ (approx. 0.00625% H₂)	Extra price for option selection 10%
Attribute Internal reference	Standard Yes
Attribute Waterproof	Standard Yes
Attribute Spatial resolution	Standard Equals outside tip diameter
Attribute Response	Standard Linear
Attribute H₂S tolerance concentration range	Standard 0-100 µM dissolved H₂S, 1,000 ppm gas

H₂

H₂-X

Stirring Sensitivity & Response Time

H₂	Stirring sensitivity	Response time (90%)	Options	Extra price for option selection
H₂ H₂-10	Stirring sensitivity <2%	Response time (90%) <10 s	Options <0.3 sec for 10-100 µm tip sizes	Extra price for option selection 15%
H₂ H₂-25	Stirring sensitivity <2%	Response time (90%) <10 s	Options <0.3 sec for 10-100 µm tip sizes	Extra price for option selection 15%
H₂ H₂-50	Stirring sensitivity <2%	Response time (90%) <10 s	Options <0.3 sec for 10-100 µm tip sizes	Extra price for option selection 15%
H₂ H₂-100	Stirring sensitivity <2%	Response time (90%) <10 s	Options <0.3 sec for 10-100 µm tip sizes	Extra price for option selection 15%
H₂ H₂-100LR*	Stirring sensitivity	Response time (90%) <10 s	Options <0.3 sec for 10-100 µm tip sizes	Extra price for option selection 15%
H₂ H₂-500 and FT-cell	Stirring sensitivity <2%	Response time (90%) <10 s
H₂ H₂-500LR	Stirring sensitivity	Response time (90%) <10 s
H₂ H₂-MR	Stirring sensitivity <2%	Response time (90%) <10 s
H₂ H₂-N	Stirring sensitivity <2%	Response time (90%) <10 s
H₂ H₂-NLR	Stirring sensitivity	Response time (90%) <10 s
H₂ H₂-NP	Stirring sensitivity <2%	Response time (90%) <10 s
H₂ H₂-NPLR	Stirring sensitivity	Response time (90%) <10 s

*Low range sensors have more sensitivity to stirring due to the larger analyte consumption rate

Stirring Sensitivity & Response Time

H₂-X	Stirring sensitivity	Response time (90%)
H₂-X H₂-X-50	Stirring sensitivity <2%	Response time (90%) <20 s
H₂-X H₂-X-100	Stirring sensitivity <2%	Response time (90%) <20 s
H₂-X H₂-X-100LR*	Stirring sensitivity	Response time (90%) <30 s
H₂-X H₂-X-500 and FT-cell	Stirring sensitivity <2%	Response time (90%) <30 s
H₂-X H₂-X-500LR	Stirring sensitivity	Response time (90%) <30 s
H₂-X H₂-X-MR	Stirring sensitivity <2%	Response time (90%) <30 s
H₂-X H₂-X-MRLR	Stirring sensitivity	Response time (90%) <30 s

*Low range sensors have more sensitivity to stirring due to the larger analyte consumption rate

H₂

H₂-X

Ordering information & Sizes

H₂	Size and description	Options	Extra price for option selection
H₂ H₂-10	Size and description 8-12 µm - glass sensor	Options 3-5 µm	Extra price for option selection 20%
H₂ H₂-25	Size and description 20-30 µm - glass sensor
H₂ H₂-50	Size and description 40-60 µm - glass sensor
H₂ H₂-100	Size and description 90-110 µm - glass sensor
H₂ H₂-100LR	Size and description 90-110 µm - glass sensor
H₂ H₂-500	Size and description 400-600 µm - glass sensor	Options 100-400 µm	Extra price for option selection 20%
H₂ H₂-500LR	Size and description 400-600 µm - glass sensor - low range
H₂ H₂-MR	Size and description 400-600 µm - in guide	Options 600-800 µm	Extra price for option selection 20%
H₂ H₂-MRLR	Size and description 400-600 µm - in guide - low range
H₂ H₂-N	Size and description 1.1 x 40 mm - needle sensor
H₂ H₂-NLR	Size and description 1.1 x 40 mm - needle sensor - low range
H₂ H₂-NP	Size and description 1.6 x 40 mm - needle sensor for piercing
H₂ H₂-NPLR	Size and description 1.6 x 40 mm - needle sensor for piercing - low range
H₂ H₂-ST-1/4	Size and description 1/4'' steel tube
H₂ H₂-SL-1/4	Size and description FT-cell 1/4'' Swagelok Tee
H₂ H₂-SL-1/8	Size and description FT-cell 1/8'' Swagelok Tee
H₂ H₂-PEEK-1/8	Size and description FT-cell 1/8'' PEEK Tee
H₂ H₂-PEEK-1/16	Size and description FT-cell 1/16'' PEEK Tee
H₂ H₂-FT-GLASS-6	Size and description Glass FT-cell 6mm outer diameter
H₂ H₂-FT-GLASS-8	Size and description Glass FT-cell 8mm outer diameter

Ordering information & Sizes

H₂-X	Size and description	Options	Extra price for option selection
H₂-X H₂-X-50	Size and description 40-60 µm - H₂S insensitive	Options 20-30 µm	Extra price for option selection 20%
H₂-X H₂-X-100	Size and description 90-110 µm - H₂S insensitive
H₂-X H₂-X-100LR	Size and description 90-110 µm - H₂S insensitive - low range
H₂-X H₂-X-500	Size and description 400-600 µm - H₂S insensitive	Options 200-400 µm	Extra price for option selection 20%
H₂-X H₂-X-500LR	Size and description 400-600 µm - H₂S insensitive - low range
H₂-X H₂-X-MR	Size and description 400-600 µm - in guide - H₂S insensitive
H₂-X H₂-X-MRLR	Size and description 400-600 µm - in guide - H₂S insensitive - low range
H₂-X H₂-X-NP	Size and description 1.6 x 40 mm - needle sensor for piercing - H₂S insensitive
H₂-X H₂-X-NPLR	Size and description 1.6 x 40 mm - needle sensor for piercing - H₂S insensitive - low range
H₂-X H₂-X-ST-1/4	Size and description 1/4'' steel tube - H₂S insensitive
H₂-X H₂-X-SL-1/4	Size and description FT-cell 1/4'' Swagelok Tee - H₂S insensitive
H₂-X H₂-X-SL-1/8	Size and description FT-cell 1/8'' Swagelok Tee - H₂S insensitive
H₂-X H₂-X-PEEK-1/8	Size and description FT-cell 1/8'' PEEK Tee - H₂S insensitive
H₂-X H₂-X-PEEK-1/16	Size and description FT-cell 1/16'' PEEK Tee - H₂S insensitive
H₂-X H₂-X-FT-GLASS-6	Size and description Glass FT-cell 6mm outer diameter - H₂S insensitive
H₂-X H₂-X-FT-GLASS-8	Size and description Glass FT-cell 8mm outer diameter - H₂S insensitive