Tangerine John

2014/05/12 專題演講
Novel palladium based catalysts for: Direct Formic Acid Fuel Cells (DFAFC) and Proton Exchange Membrane Fuel Cells (PEMFC)
Andrzej Borodziński
Institute of Physical Chemistry, Polish Academy of Sciences

Anode catalysts
1. Novel self-activating Ru/Pd/C catalysts for DFAFC
2. CO resistance anode RuPt/Pd/C catalysts for PEMFC

Renewable energy and fuel cells
source: solar, wind, biomass

Carnot Principle

Low temperature fuel cells for portable applications

mobile phones: 6V, 6W
notebook: 6V, 30W
fuel cell cars: 50kW

The common usage of PEMFC is limited by:
- technical problems with hydrogen storage
- high cost of Pt

Anode:
HCOOH → CO2 + 2H+ + 2e-

Cathode:
1/2 O2 + 2H+ + 2e- → 2H2O

Overal reaction:
HCOOH + 1/2 O2 → CO2 + H2O

Formic Acid:
FA as a liquid it is easy to handle.
Higher power density than direct methanol fuel cell (DMFC).

Palladium alloys used as catalysts cheaper than Pt or Au alloys...

2011/09/27 experiment
3M formic acid HPLC, i = 20 mA/mg Pd catalyst, pump 0.45 ml/min

Deactivation of the Pd catalysts working with less expensive formic acid.

Catalysts resistant from the CO gas...

Formaldehyde CH3COOH
Methyl Formate HCOOCH3
Formic Acid HCOOH
Methanol CH3OH

(fcc) palladium structure peaks: (111), (200), (220) and (311) at 2 theta values of 42.2, 46.5, 68.2 and 82.0 degrees, respectively.

In the working conditions of fuel cell Pd the surface layer of PdO is reduced to Pd by FA and Pd particles determined by XRD are larger than in the fresh particle.

Anode:
2.5 mg/cm2 catalyst
3 M HCOOH
flow rate 0.5 ml/min

Cathode:
60 % Pt/Vulcan, 4 mg/cm2 Pt
O2 flow rate 1000 ml/min
current density 10 mA/cm
temperature 30 oC