Media Releases

Saving sunshine for a rainy day: New catalyst offers efficient storage of alternative energies

March 24, 2016

Toron­to, ON — We can’t con­trol when the wind blows and when the sun shines, so find­ing effi­cient ways to store ener­gy from alter­na­tive sources remains an urgent research prob­lem. Now, a group of researchers led by Pro­fes­sor Ted Sar­gent at the Uni­ver­si­ty of Toronto’s Fac­ul­ty of Applied Sci­ence & Engi­neer­ing may have a solu­tion inspired by nature.

The team has designed the most effi­cient cat­a­lyst for stor­ing ener­gy in chem­i­cal form, by split­ting water into hydro­gen and oxy­gen, just like plants do dur­ing pho­to­syn­the­sis. Oxy­gen is released harm­less­ly into the atmos­phere, and hydro­gen, as H2, can be con­vert­ed back into ener­gy using hydro­gen fuel cells.

“Today on a solar farm or a wind farm, stor­age is typ­i­cal­ly pro­vid­ed with bat­ter­ies. But bat­ter­ies are expen­sive, and can typ­i­cal­ly only store a fixed amount of ener­gy,” says Sar­gent. “That’s why dis­cov­er­ing a more effi­cient and high­ly scal­able means of stor­ing ener­gy gen­er­at­ed by renew­ables is one of the grand chal­lenges in this field.”

You may have seen the pop­u­lar high-school sci­ence demon­stra­tion where the teacher splits water into its com­po­nent ele­ments, hydro­gen and oxy­gen, by run­ning elec­tric­i­ty through it. Today this requires so much elec­tri­cal input that it’s imprac­ti­cal to store ener­gy this way — too great pro­por­tion of the ener­gy gen­er­at­ed is lost in the process of stor­ing it.

This new cat­a­lyst facil­i­tates the oxy­gen-evo­lu­tion por­tion of the chem­i­cal reac­tion, mak­ing the con­ver­sion from H2O into O2 and H2 more ener­gy-effi­cient than ever before. The intrin­sic effi­cien­cy of the new cat­a­lyst mate­r­i­al is over three times more effi­cient than the best state-of-the-art cat­a­lyst.

The new cat­a­lyst is made of abun­dant and low-cost met­als tung­sten, iron and cobalt, which are much less expen­sive than state-of-the-art cat­a­lysts based on pre­cious met­als. It showed no signs of degra­da­tion over more than 500 hours of con­tin­u­ous activ­i­ty, unlike oth­er effi­cient but short-lived cat­a­lysts. Their work was pub­lished today in the lead­ing jour­nal Sci­ence.

“With the aid of the­o­ret­i­cal pre­dic­tions, we became con­vinced that includ­ing tung­sten could lead to a bet­ter oxy­gen-evolv­ing cat­a­lyst. Unfor­tu­nate­ly, pri­or work did not show how to mix tung­sten homo­ge­neous­ly with the active met­als such as iron and cobalt,” says Dr. Bo Zhang, one of the study’s lead authors. “We invent­ed a new way to dis­trib­ute the cat­a­lyst homoge­nous­ly in a gel, and as a result built a device that works incred­i­bly effi­cient­ly and robust­ly.”

This research unit­ed engi­neers, chemists, mate­ri­als sci­en­tists, math­e­mati­cians, physi­cists, and com­put­er sci­en­tists across three coun­tries. A chief part­ner in this joint the­o­ret­i­cal-exper­i­men­tal stud­ies was a lead­ing team of the­o­rists at Stan­ford Uni­ver­si­ty and SLAC Nation­al Accel­er­a­tor Lab­o­ra­to­ry under the lead­er­ship of Dr. Alek­san­dra Vojvod­ic. The inter­na­tion­al col­lab­o­ra­tion includ­ed researchers at East Chi­na Uni­ver­si­ty of Sci­ence & Tech­nol­o­gy, Tian­jin Uni­ver­si­ty, Brookhaven Nation­al Lab­o­ra­to­ry, Cana­di­an Light Source and the Bei­jing Syn­chro­tron Radi­a­tion Facil­i­ty.

“The team devel­oped a new mate­ri­als syn­the­sis strat­e­gy to mix mul­ti­ple met­als homo­ge­neous­ly — there­by over­com­ing the propen­si­ty of mul­ti-met­al mix­tures to sep­a­rate into dis­tinct phas­es,” said Jef­frey C. Gross­man, the Mor­ton and Claire Goul­der and Fam­i­ly Pro­fes­sor in Envi­ron­men­tal Sys­tems at Mass­a­chu­setts Insti­tute of Tech­nol­o­gy. “This work impres­sive­ly high­lights the pow­er of tight­ly cou­pled com­pu­ta­tion­al mate­ri­als sci­ence with advanced exper­i­men­tal tech­niques, and sets a high bar for such a com­bined approach. It opens new avenues to speed progress in effi­cient mate­ri­als for ener­gy con­ver­sion and stor­age.”

“This work demon­strates the util­i­ty of using the­o­ry to guide the devel­op­ment of improved water-oxi­da­tion cat­a­lysts for fur­ther advances in the field of solar fuels,” said Gary Brud­vig, a pro­fes­sor in the Depart­ment of Chem­istry at Yale Uni­ver­si­ty and direc­tor of the Yale Ener­gy Sci­ences Insti­tute.

“The inten­sive research by the Sar­gent group in the Uni­ver­si­ty of Toron­to led to the dis­cov­ery of oxy-hydrox­ide mate­ri­als that exhib­it elec­tro­chem­i­cal­ly induced oxy­gen evo­lu­tion at the low­est over­po­ten­tial and show no degra­da­tion,” said Uni­ver­si­ty Pro­fes­sor Gabor A. Somor­jai of the Uni­ver­si­ty of Cal­i­for­nia, Berke­ley, a leader in this field. “The authors should be com­pli­ment­ed on the com­bined exper­i­men­tal and the­o­ret­i­cal stud­ies that led to this very impor­tant find­ing.”

Pro­fes­sor Sar­gent is the Cana­da Research Chair in Nan­otech­nol­o­gy. The group’s work was sup­port­ed in large part by the Ontario Research Fund—Research Excel­lence Pro­gram, NSERC, the CIFAR Bio-Inspired Solar Ener­gy Pro­gram and the U.S. Depart­ment of Ener­gy.

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About the Fac­ul­ty of Applied Sci­ence & Engi­neer­ing at the Uni­ver­si­ty of Toron­to

The Uni­ver­si­ty of Toron­to’s Fac­ul­ty of Applied Sci­ence & Engi­neer­ing is Canada’s top engi­neer­ing school and ranks among the best in the world. We pride our­selves on our cross-dis­ci­pli­nary edu­ca­tion, col­lab­o­ra­tive research and glob­al impact. We are locat­ed in down­town Toron­to, a vibrant and diverse city rec­og­nized glob­al­ly as a hub for inno­va­tion. With approx­i­mate­ly 7,800 stu­dents, 245 fac­ul­ty and 16 build­ings, we are one of Canada’s largest engi­neer­ing schools. U of T Engi­neer­ing fac­ul­ty mem­bers hold more than 70 pres­ti­gious research chairs fund­ed by gov­ern­ment, indus­try and endow­ments. Our fac­ul­ty mem­bers won 21 per cent of major awards received by Cana­di­an engi­neer­ing pro­fes­sors in 2015 — three times as many as any oth­er Cana­di­an engi­neer­ing school — while rep­re­sent­ing less than six per cent of engi­neer­ing pro­fes­sors nation­wide.

Media con­tact: Mar­it Mitchell Com­mu­ni­ca­tions & Media Rela­tions Strate­gist
Fac­ul­ty of Applied Sci­ence & Engi­neer­ing, Uni­ver­si­ty of Toron­to
+1–416-978‑4498; marit.mitchell@utoronto.ca