PMID- 16511617
OWN - NLM
STAT- MEDLINE
DCOM- 20060503
LR  - 20131121
IS  - 1473-0197 (Print)
IS  - 1473-0189 (Linking)
VI  - 6
IP  - 3
DP  - 2006 Mar
TI  - A passive microfluidic hydrogen-air fuel cell with exceptional stability and high 
      performance.
PG  - 353-61
AB  - We describe an advanced microfluidic hydrogen-air fuel cell (FC) that exhibits 
      exceptional durability and high performance, most notably yielding stable output 
      power (>100 days) without the use of an anode-cathode separator membrane. This FC 
      embraces an entirely passive device architecture and, unlike conventional 
      microfluidic designs that exploit laminar hydrodynamics, no external pumps are 
      used to sustain or localize the reagent flow fields. The devices incorporate high 
      surface area/porous metal and metal alloy electrodes that are embedded and fully 
      immersed in liquid electrolyte confined in the channels of a 
      poly(dimethylsiloxane) (PDMS)-based microfluidic network. The polymeric network 
      also serves as a self-supporting membrane through which oxygen and hydrogen are 
      supplied to the cathode and alloy anode, respectively, by permeation. The 
      operational stability of the device and its performance is strongly dependent on 
      the nature of the electrolyte used (5 M H2SO4 or 2.5 M NaOH) and composition of 
      the anode material. The latter choice is optimized to decrease the sensitivity of 
      the system to oxygen cross-over while still maintaining high activity towards the 
      hydrogen oxidation reaction (HOR). Three types of high surface area anodes were 
      tested in this work. These include: high-surface area electrodeposited Pt (Pt); 
      high-surface area electrodeposited Pd (Pd); and thin palladium adlayers supported 
      on a "porous" Pt electrode (Pd/Pt). The FCs display their best performance in 5 M 
      H2SO4 using the Pd/Pt anode. This exceptional stability and performance was 
      ascribed to several factors, namely: the high permeabilities of O2, H2, and CO2 
      in PDMS; the inhibition of the formation of insoluble carbonate species due to 
      the presence of a highly acidic electrolyte; and the selectivity of the Pd/Pt 
      anode toward the HOR. The stability of the device for long-term operation was 
      modeled using a stack of three FCs as a power supply for a portable display that 
      otherwise uses a 3 V battery.
FAU - Mitrovski, Svetlana M
AU  - Mitrovski SM
AD  - Department of Chemistry, University of Illinois at Urbana-Champaign and Frederick 
      Seitz Materials Research Laboratory, 600 S. Mathews, Urbana, IL 61801, USA.
FAU - Nuzzo, Ralph G
AU  - Nuzzo RG
LA  - eng
PT  - Journal Article
DEP - 20060123
PL  - England
TA  - Lab Chip
JT  - Lab on a chip
JID - 101128948
RN  - 7YNJ3PO35Z (Hydrogen)
SB  - IM
MH  - Air
MH  - *Electric Power Supplies
MH  - Electrochemistry
MH  - Electrodes
MH  - Equipment Design
MH  - Hydrogen/*chemistry
MH  - Microfluidic Analytical Techniques/*instrumentation/*methods
MH  - Sensitivity and Specificity
MH  - Time Factors
EDAT- 2006/03/03 09:00
MHDA- 2006/05/04 09:00
CRDT- 2006/03/03 09:00
PHST- 2006/03/03 09:00 [pubmed]
PHST- 2006/05/04 09:00 [medline]
PHST- 2006/03/03 09:00 [entrez]
AID - 10.1039/b513829a [doi]
PST - ppublish
SO  - Lab Chip. 2006 Mar;6(3):353-61. doi: 10.1039/b513829a. Epub 2006 Jan 23.