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Dalhousie University. Comparison of Electrodeposited Cu-Zn Alloys Prepared Individually and Combinatorially. Shane Beattie and J. R. Dahn Dalhousie University, Halifax, N.S., Canada. Motivation - Combinatorial. Combinatorial methods provide a new paradigm for advancing scientific discovery.
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Dalhousie University Comparison of Electrodeposited Cu-Zn Alloys Prepared Individually and Combinatorially Shane Beattie and J. R. Dahn Dalhousie University, Halifax, N.S., Canada
Motivation - Combinatorial • Combinatorial methods provide a new paradigm for advancing scientific discovery. • Hundreds or even thousands of similar, but unique, materials can be created in a single experiment and then tested for a desired property. • Combinatorial methods must be able to be scaled to industrial sized proportions.
Cu rich Zn Ni foil Hull Cell Zn rich Combinatorial Electrodeposition 0.3M Zn2+ (-0.76 V SHE) 0.013M Cu2+ (0.16 V SHE) 23:1Zn:Cu Cu deposition is diffusion controlled
} -CuZn + (Cu) -CuZn } -CuZn5 + -CuZn A range of Cu-Zn alloys 0 10
Bulk Alloys -Pulsed Deposition • If a commercially viable product is discovered using combinatorial methods the fabrication process must be easily scaled to industrial sized proportions. • To test the scalability of our combinatorial methods we prepared copper-zinc alloys in bulk using antiquated, one-at-a-time methods. • Bulk alloys were deposited under the same conditions as the alloys prepared combinatorially, except a pulsed current was used instead of constant current.
Pulsed Waveform Zn deposition Cu2++Zn Cu+Zn2+
Bulk Alloys -Pulsed Deposition Zn% (Cu) 14 20 25 -CuZn ' 45 54 60 -CuZn5 75
XRD: Combinatorial vs. Pulsed Selected Scans Zn % Pulsed Zn % Combinatorial 30 25 70 75
Combi, one bath, one run, 1hr, range of compositions One by one, seven baths, seven runs, 50hrs, discrete compositions
Conclusion Combinatorial Electrodeposition is: • Scalable - structure and composition of alloys prepared by combinatorial methods are representative of bulk alloys • Inexpensive - The experiment could be performed using tupperware and a D-cell • Fast - Experiment took less than an hour • Simple - No special equipment is required, except for chemicals everything you need can be bought from Canadian Tire • Combinatorial methods via electrodeposition embody, and even extend, the advantages of combinatorial methods: “faster, better, cheaper, simpler and scalable”.
Acknowledgements Dalhousie University • Jeff Dahn and Dahn Lab members, past and present
Recent Developments • Cu-Zn is just one example of the power of combinatorial electrodeposition. We’ve also explored binary Cu-Sn and Sn-Zn composition-spread films. • We’re no longer limited to binary systems. We recently developed a simple method to fabricate composition-spread libraries of ternary films • Ternary films are deposited such that composition gradients are parallel or orthogonal to one another
Sn Sn Zn Zn Need a 3rd element, Cu Cu solution
Sn Zn Cu
5V Water Guns!
Conclusions II • Composition-spread ternary alloys can be fabricated • Like combinatorial electrodeposition, the method is simple, fast, inexpensive, and versatile. • A little ingenuity goes a long way. Good science can be done without expensive, complicated equipment.
Sn rich Zn Ni foil Hull Cell Zn rich Deposit Binary Alloys First 0.3M Zn2+ (-0.76V SHE) 0.013M Sn2+ (-0.14V SHE) 23:1Zn:Sn Sn deposition is diffusion controlled
A range of Cu-Zn alloys 0 Multi-phased Nanocrystaline Multi-phased, crystalline 10