Platinum (Pt) Coil Counter Electrode

Description

백금 상대전극은 외경 6.6mm PTFE 본체를 특징으로 하며, 표면적이 약 4.7cm²인 외경 0.5mm 백금(Pt) 와이어 코일로 마감되어 있습니다. 이 상대전극은 표준 용량 전기화학 셀에 사용하기에 이상적으로 설계되었지만, 이러한 셀에만 국한되지는 않습니다. 프릿 분리 튜브를 원하지 않는 고객은 이 제품만 단독으로 사용할 수도 있습니다. 이 상대전극은 백금 상대전극 어셈블리의 일부로도 제공됩니다.

Documention

 Q&A. 백금 또는 그라파이트 상대 전극 선택 요령은?

Let’s first review the purpose of the counter electrode. The counter electrode completes the circuit for the potentiostat and drives current through the electrochemical cell. As such, the counter electrode has to have a large area than the working electrode and be sufficiently active at passing current through the electrochemical cell, while still being “inert” to not affect the electrochemistry at the working electrode.

With that said, the platinum counter electrode has a smaller area than the graphite rod and is more expensive. However, the platinum counter electrode is more “active” than the graphite rod, meaning that it intrinsically passes current more easily than the graphite rod electrode. Some researchers might need to add a “sacrificial agent” to the counter electrode if there is nothing for the counter electrode to oxidize or reduce. Platinum is so good at oxidizing and reducing that a sacrificial agent is rarely needed, but it might be needed for a graphite rod (depends on the system). Because it requires more voltage to drive a current through the graphite rod, the user would benefit from using a potentiostat with a large compliance voltage. Compliance voltage is rarely an issue, but it can be an issue with some customer setups

The last consideration is platinum or carbon contamination. If the customer is doing CO2 reduction research, using a graphite rod could be problematic because the graphite could leech out of counter electrode and produce false positives. However, the same argument could be made for platinum, and that platinum from the counter electrode is getting on the working electrode and contaminating your system.