The U of T Solar Fuels Cluster is an interdisciplinary research team devoted to developing scalable, cost effective materials solutions towards using CO2 as a chemical feedstock for valuable products. Leveraging the expertise of some of Canada's leading chemists, engineers, and material scientists, we hope to initiate a paradigm-shifting zero-emission CO2 economy.
October 25th: Gigawatt Electricity Storage Using Water and Rocks
The dominant technology for the large-scale storage and retrieval of electricity is pumped hydro - electrical energy. In this approach, electricity is converted to gravitational potential energy by moving water uphill and is then retrieved by allowing the water to flow downhill through a turbine. However, a new concept in gravity storage eliminates the need for hills and simply uses water pumps to hydraulically lift massive rocks in an underground shaft. The acquired potential energy is reclaimed as electricity by discharging the water under pressure though a turbine. See full article at Advanced Science News.
October 17th, 2019: Beyond Haber-Bosch: Non-Equilibrium Photocatalysis
A recent report in which the thermodynamic equilibrium limit of the Haber-Bosch synthesis of ammonia was, for the first time, surmounted by the action of light, and could change the prevailing view of what is possible and not possible in the field of catalysis. A hetero-nanostructured photocatalyst, Fe-TiO2-xHy, which contains both a high and low-temperature site in a single structure has been demonstrated to overcome the thermodynamic equilibrium limit of the ammonia synthesis. This is possible because the exothermic ammonia synthesis process is thermodynamically favored though kinetically sluggish at low temperature; however, the exact opposite prevails at high temperature. See full article at Advanced Science News.
October 14th, 2019: Climate Change Will Require Heavy Lifting
As the global hunger for electricity grows and the transition to solar and wind accelerates, electricity storage capacity is urgently needed to handle the challenges of scale and intermittency. Concrete solutions are needed to solve the large-scale electricity storage problem for both daily and seasonal applications, and it’s going to require some heavy lifting. A new generation of gravity batteries have emerged based on the lifting and lowering massive concrete weights. The solution may prove a viable option for storing and releasing grid scale electrical energy over periods as short as seconds to as long as months, which would represent a significant step towards renewable energy utilization. See full story at Advanced Science News.
October 9th, 2019: A Whale of a Solution to Climate Change
Strategies to enhance the carbon capacity of the terrestrial and oceanic sinks tend to focus on landscapes – forest canopy, soil composition, and sea water chemistry. However, we must not neglect the role of animals in maintaining the natural carbon cycle. As it turns out, whales have the capacity to absorb enormous amounts of atmospheric carbon dioxide (CO2). Estimates place the carbon sequestering capacity of a whale to be similar to around 1000 trees with an average whale capturing up to 33 tons of CO2 over its 60-year lifetime, centuries. Efforts to re-establish whale populations, together with large scale reforestation, therefore offer a surprinsingly impactful solution to meeting global emission targets. See full article at Advanced Science News.
October 4th, 2019: Congratulations to Hong Wang et al. on their publication in Advanced Science, “Heterostructure Engineering of a Reverse Water Gas Shift Photocatalyst”
The paper describes a heterostructure engineering strategy that enables the gas-phase, photocatalytic, heterogeneous hydrogenation of CO2 to CO with high performance metrics. The catalyst is comprised of indium oxide nanocrystals (In2O3-x(OH)y) nucleated and grown on the surface of niobium pentoxide nanorods. Materials characterization demonstrates that the Nb2O5 support in the In2O3-x(OH)y@Nb2O5 heterostructure increases the number of oxygen vacancies and lengthens the excited state charge carrier lifetimes in the attached In2O3-x(OH)y nanocrystals, which results in a 44-fold higher conversion rate than pristine In2O3-x(OH)y selective conversion of CO2 to CO as well as long-term operational stability. Overall, the results of this study bode well for the general applicability of the heterostructure engineering approach for optimizing the performance of photocatalytic heterogeneous CO2 conversion reactions. See full article at Advanced Science.
September 20th, 2019: SF6 Worries - The Most Potent and Persistent Greenhouse Gas
It is not well known, but the most potent greenhouse gas is, surprisingly, neither carbon dioxide nor methane, but a colorless, odorless, and inert gas known as sulfur hexafluoride (SF6). With a global warming potential 23,900 times that of CO2 and being synthetic in nature (it is not absorbed on destroyed naturally), rising SF>6 concentrations are of major concern. Currently, electrical utilities and equipment are responsible for consuming 80% of the 10 000 tons of SF6 produced every year, an amount which is growing with the increasing global production and demand for renewable forms of energy, such as wind and solar. Can chemists and engineers rise to the challenge of solving the looming SF6 problem? See full article at Advanced Science News.
September 16th, 2019: Congratulations to Young and co-authors on their article in JACS
Atomically precise heterostrucutures present chemically interesting active sites for catalysis but are often expensive and/or challenging to synthesize. In this article, we report a synthetic strategy to conformally coating Cu atoms onto the surface of Pd/HyWO3-x by anchoring Cu(I)OtBu to the Brønsted acidic protons of the bronze. It was observed that just 0.2 at.% of Cu was able to increase the catalytic performance of CO2 hydrogenation to CO by 500%. This metal anchoring method enables atom precise modification of the surfaces of metal oxide nanomaterials for catalytic applications, circumventing the need for complex and expensive atomic layer deposition processes. See full article at Journal of the American Chemical Society.
September 9th, 2019: Congratulations to Lili Wan, Wei Sun, & co-authors on their article in Nature Catalysis
A long-standing challenge in the field of CO2 utilization is how to stabilize Cu2O, an earth-abundant, non-toxic, low-cost (photo)catalyst that can facilitate reduction of CO2 to CO against the irreversible redox disproportionation Cu2O → Cu + CuO, responsible for its instability.
Lili Wan and Wei Sun and coworkers in the Ozin group have solved this problem as reported in their Nature Catalysis paper, by modifying the surface of Cu2O nanocubes with a mixed valence surface frustrated Lewis pair (SFLP), Cu(I,II) ●● OH, which serves to eliminate the redox disproportionation. As depicted in the illustration, H2 undergoes heterolytic dissociation on the SFLP, water is eliminated to create an [O] vacancy and Cu(I) is reduced to Cu(0). Adsorption of CO2 at the [O] vacancy site drives the conversion to CO thereby completing the photocatalytic RWGS reaction cycle. See full article at Nature Catalysis online.
August 13th, 2019: Congratulations to Dr. Zaiyong Jiang et al. on their paper, "Building a Bridge from Papermaking to Solar Fuels"
Everybody knows the leaf makes carbohydrates and the trunk makes paper. But did you know that waste from the paper making process can make fuel from carbon dioxide, water and sunlight? Black liquor, an industrial waste product of papermaking, is primarily used as a low‐grade combustible energy source. Despite its high lignin content, the potential utility of black liquor as a feedstock in products manufacturing, remains to be exploited. In this paper, black liquor is demonstrated to function as a primary feed‐stock for synthesizing graphene quantum dots that exhibit both up‐conversion and photoluminescence when excited using visible/near‐infrared radiation, enabling solar‐powered generation of H2 from H2O, and CO from H2O–CO2, using broadband solar radiation. See full article at Angewandte Chemie.
August 7th, 2019: Congratulations to Zaiyong Jiang, Wei Sun, & co-authors on their article in Advanced Science
In their paper, “Living Atomically Dispersed Cu Ultrathin TiO2 Nanosheet CO2 Reduction Photocatalyst”, Jiang, Sun, and co-authors report a serendipitous living photodeposition method can make atomically dispersed Cu immobilized on ultrathin TiO2 nanosheets, which can photocatalytically reduce an aqueous solution of CO2 to CO and in the process can be recycled in a straightforward procedure on becoming oxidatively deactivated. See full article at Advanced Science.
July 17th, 2019: Fundamentals and Applications of Photocatalytic CO2 Methanation
Light-driven methanation of CO2 holds great promise to close the carbon cycle and store and transport intermittent solar energy in the form of the chemical bonds of synthetic, “solar” methane. In their Review article published in Nature Communications, Geoffrey Ozin, Uli Ulmer and co-authors critically appraise the latest scientific discoveries in the field of photocatalytic CO2 methanation. The photocatalytic methanation schemes explored include photothermal, plasmonic, biophoto, heterogeneous and homogeneous photoredox methanation. Photocatalytic CO2 methanation could eventually replace fossil CH4 if implemented at a large scale.
July 5th, 2019: Challenges of Electrifying Heterogeneous Catalysis
How can we replace the fossil-fuel-derived heat that conventionally drives chemical processes with an emissions-free alternative? The current standard in industrial-scale heterogeneous catalytic processes, such as the production of ammonia and hydrogen, is to use heat supplied by the combustion of natural gas. Heat can alternatively be supplied from non-fossil sources, such as renewable electricity; however, assessing the net impact on carbon emissions of electricity-based processes remains non-trivial. Read full article at Advanced Science News.
June 21th, 2019: Electrochemical Carbon Dioxide Reduction in Supercritical Carbon Dioxide is Cool
At standard temperature and pressure, CO2 exists as a gas. On cooling to -78.5 °C, it becomes a solid called dry ice, which is a common refrigerant. At a critical temperature of 31.1 °C and pressure 72.9 atmospheres, however, CO2 becomes a supercritical fluid with properties intermediate to a gas and liquid. In this form, CO2 fills a containment vessel and exhibits a low viscosity reminiscent of a gas but retains the high density of a liquid. It turns out that supercritical CO2 also has rather appealing properties as both solvent and reagent in the electrochemical reduction of CO2 to a variety of products. Read full article at Advanced Science News.
June 13th, 2019: Congratulations to Dr. Xiaoliang Yan and co-authors on their paper, “Nickel@Siloxene catalytic nanosheets for high-performance CO2 methanation”
Two-dimensional materials hold great potential as catalysts for the heterogeneous conversion of CO2 to synthetic fuels and chemicals. In this paper, Yan et al. demonstrate the performance of nickel@siloxene to be highly sensitive to the nickel component being located either on the interior or exterior of adjacent siloxene nanosheets. Control over the location of nickel is achieved by employing the terminal groups of siloxene and varying the solvent used during its nucleation and growth, which ultimately determines the distinct reaction intermediates and pathways for the catalytic CO2 methanation. A CO2 methanation rate of 100 mmol gNi−1 h−1 is achieved with over 90% selectivity when nickel resides specifically between the sheets of siloxene.. See full paper at Nature Communications.
June 10th, 2019: Congratulations to Dr. Tingjiang Yan and co-authors on their paper, “Polymorph selection towards photocatalytic gaseous CO2 hydrogenation”
Titanium dioxide is the only known material that can enable gas-phase CO2 photocatalysis in its anatase and rutile polymorphic forms. In their paper, however, Dr. Yan and co-authors demonstrate that the lesser known rhombohedral polymorph of indium sesquioxide, like its well-documented cubic polymorph, can act as a CO2 hydrogenation photocatalyst with the ability to produce CH3OH and CO. See full paper at Nature Communications.
June 5th, 2019: Electricity-free Renewable Hydrogen
A recent paper published in the Proceedings of the National Academy of Science has reported that applying carbon capture and utilization (CCU) to manufacture the top 20 commodity chemicals could mitigate up to of 3.5 gigatonnes of carbon emmisions annually, equivalent of nearly 10% of the emissions released in 2018. The study found CCU’s potential to be contingent on whether the vast amount of electricity it would require could actually be provided given the limited renewable electricity infrastructure that currently exists. How do we decide which energy-consuming processes should be made priority? Read full article at Advanced Science News.
May 21st, 2019: Global Carbon Dioxide Cooling
It may come as a surprise, but carbon dioxide, the infamous greenhouse gas driving climate change, is also a leading contender in the replacement of hydrofluorocarbons in the next-generation of “green” refrigeration systems. It offers many advantages over second and third generation refrigerants, including higher volumetric cooling capacity, lower operating temperatures, non-flammability, reduced operating costs, and lower global warming potential. See full article at Advanced Science News.
May 14th, 2019: Congratulations to Dr. Lu Wang and co-authors on their paper in Angewandte Chemie!
Surface Frustrated Lewis Pairs (SFLPs) have been implicated in the gas‐phase heterogeneous (photo)catalytic hydrogenation of CO2 via the cubic form of hydroxylated indium oxide. In their paper, Dr. Wang and co-authors report the room temperature dissociation of molecular hydrogen via SFLPs on the rhombodral form of the catalyst, which is shown to favour the heterolysis over the homolysis reaction pathway. See full article at Angewandte Chemie.
May 3rd, 2019: Is Air Conditioning Cool?
When one thinks of the major sources of anthropogenic emissions entering the earth’s atmophsere, chances are that air conditioning (AC) isn’t the first to come to mind. However, the carbon footprint of AC systems is far from negligeable: they are expected to contribute an additional 167 gigatonnes of CO2 by 2050. But what if AC systems could be re-designed to provide an opportunity to capture CO2 from the air? Global adoption of on-site conversion of CO2 from AC systems into chemicals and fuels could have a key role in addressing global climate change. Read the full article at Advanced Science News.
May 1st, 2019: Crowd oil not crude oil
Congratulations to authors Prof. Roland Dittmeyer, Michael Klumpp, Paul Kant, and Prof. Geoffrey Ozin on the release of their Nature Communications article, “Crowd oil not crude oil”. The delocalized nature of climate change poses a major challenge to mitigation efforts. The authors propose retrofitting air conditioning units to convert water and carbon dioxide into fuel. The users would collect the synthetically-made oil for their personal use, or to redistribute within their community, as to encourage decentralized CO2 conversion and energy democratization. Read the full article at Nature Communications.
April 25th, 2019: Advanced Science News: “Spamming Science”
The internet has had profound effects on virtually all aspects of society. It has revolutionized every part of our lives, from the ways in which we engage and communicate, to our shopping and entertainement habits, to our media and politics. But what of the effect of the internet age on academia? As one of the earliest adopters of email communication, academics have witnessed the many ways in which the internet has shifted the nature of scientific collaborations, publishing processes, and research patterns. Have we, however, reached a point where electronic communication has become more problematic than beneficial to academic research? Read Prof. Ozin and Prof. Seferos’s take in Advanced Science News.
April 20th, 2019: Congratulations to Athan Tountas & co-authors for having their review article featured in Advanced Science’s 5 Year Anniversary Digital Issue!
On the occasion of its 5th anniversary, Advanced Science’s virtual issue collects a celebratory series of invited-only articles which showcase the outstanding achievements of leading international researchers in the field of materials science, physics and chemistry, medical and life sciences, as well as engineering. In their article, “Towards Solar Methanol: Past, Present, and Future”, Athan Tountas and co-authors provide an overview of how conventional industrial-scale fossil-enabled heterogeneous catalytic conversion of carbon monoxide and hydrogen to methanol is being challenged by more sustainable electrocatalytic, photocatalytic, biocatalytic, and solar thermal methods using carbon dioxide and water as feed-stocks. See full article at Advanced Science. Cover art courtesy of Dr. Chenxi Qian.
April 11th, 2019: Energy & Environmental Science Cover Page!
Congratulations to authors Mireille Ghoussoub, Meikun Xia, Dr. Paul Duchesne, and Prof. Dvira Segal, as well as cover artist and alumnus, Dr. Chenxi Qian, for having their recently published review article featured on the cover of Energy and Environmental Science. Photothermal catalysis is an emerging sub-discipline of heterogeneous catalysis that exploits broad absorption of the solar spectrum to stimulate a combination of thermochemical and photochemical processes, which contribute synergistically to driving catalytic reactions. It is proving an effective and promising strategy for converting CO2 to synthetic fuels. See full article at Energy & Environmental Science.
March 20th, 2019: Putting a Spin on a Carbon Photocatalysis Spin-off
Chemicals and fuels derived from CO2 and enabled by solar power have taken the research world by storm over the past decade. However, CO2-derived fuel technologies, as promising as they may appear, are still subject to the harsh economic realities of chemical engineering. Is it possible to simultaneously achieve high photonic efficiencies all whilst adhering to the logic of economies of scale? Two new start-ups, The Solistra Corporation and Dimensional Energy, have taken on this challenge and are paving the way towards a future driven by solar fuel technology. Read full story at Advanced Science News.
February 22nd, 2019: Industrial Carbon Dioxide Photoctatalysis
Where did the use of light to drive catalytic reactions all begin? Why are metal oxides a good choice for light-assisted chemical reactions? How can we design better photoreactors to integrate into the existing chemical infrastructure? Finally, what are the prospects for global industrial photocatalysis? Learn the answers to all these questions and more as the University of Toronto Solar Fuels Group shines light some of the technological challenges facing the widespread industrialization of CO2 photocatalysis. Read full story at Advanced Science News.
February 21th, 2019: Congratulations Dr. Yang-Fan Xu on being selected as a recipient of the 2019 University of Toronto, Faculty of Arts & Science Postdoctoral Fellowship Award
The Faculty of Arts and Science (FAS) Postdoctoral fellowship is a highly competitive and prestigious award designed to provide outstanding recent doctoral students advanced training in their field of study. This year the FAS received over 140 applicants. The Solar Fuels Groups is pleased to announce that Dr. Yang-Fan among the few selected recipients.
February 19th, 2019: Congratulations to Athan Tountas and Co-authors on your Solar Methanol Advanced Science Paper!
“Towards Solar Methanol: Past, Present, and Future” provides a comprehensive overview of how value-added products, notably methanol, can be produced affordably and sustainably from greenhouse gases. Harnessing light in the form of solar energy can assist is the production process in some capacity through various strategies, such as solar-thermochemical, photochemical, and photovoltaic-electrochemical. Commercially-ready technologies are compared via technoeconomic analysis, and the scalability of solar reactors is also discussed in the context of light-incorporating catalyst architectures and designs. Finally, the review offers perspective on the viability of the most promising solar methanol strategy to be applied at a global scale. Read full story at Advanced Science.
January 10th, 2019: Catalytic CO2 Reduction by Palladium Decorated Silicon Hydride Nanosheets
Congratulations to Wei, Chenxi, Govind, and Co-Authors on their New Years Eve Nature Catalysis publication in which they report on their discovery of how to make Silicon, the second most abundant element on earth, behave catalytically in the gas-phase heterogeneous hydrogenation of CO2 to CO, known as the Reverse Water Gas Shift Reaction. See full article at Nature Catalysis.
January 8th, 2019: Congratulations Mireille, Dvira, Meikun, and Paul on your EES article which shows how producing synthetic fuels by photothermal gas-phase heterogeneous CO2 catalysis is within our hands!
Photothermal catalysis is an emerging sub-discipline of heterogeneous catalysis that exploits broad absorption of the solar spectrum to stimulate a combination of thermochemical and photochemical processes, which contribute synergistically to driving catalytic reactions. In particular, it is proving an effective and promising strategy for converting CO2 to synthetic fuels. See full article at Energy & Environmental Science.
December 20th, 2018: The Agnotology of Carbon Dioxide
In 1995, Robert Proctor of Stanford University coined the term, “Agnotology”, refering to the study of how and why we do not know things as a means of addressing the rapid dissemination of misleading, confusing, frightening and false information. Although early works in this field were focused on the understanding the ignorance around smoking and cancer risk, Agnotogy is highly relevant to the current rhetoric surrounding climate change. The reality is that CO2 emissions due to human activity are contributing to climate change and that to limit the warming from pre-industrial levels to 1.5 °C these emissions must be reduced to zero by 2050. Unfortunately, however, denial or acceptance of global warming often stems from selectivity in the search for evidence and political leaning. See full story at: Advanced Science News.
December 18th, 2018: Congratulations to Dr. O’Brien et al. on their paper “Enhanced photothermal reduction of gaseous CO2 over silicon photonic crystal supported ruthenium at ambient temperature”
Solar-driven CO2 hydrogenation can provide a renewable source of fuels and reduce greenhouse gas emissions at industrial scale. The paper investigates the light-driven Sabatier reaction over Ru films sputtered onto silica opal (Ru/SiO2) and inverted silicon opal photonic crystal (Ru/i-Si-o) supports. Under ambient temperature conditions, photomethanation rates over both the Ru/SiO2 and Ru/i-Si-o catalysts were shown to increase significantly with increasing light intensity, and rates as large as 2.8 mmol g−1 h−1 are achieved over the Ru/i-Si-o catalyst. Furthermore, the quantum efficiency of the photomethanation reaction was found to be almost three times larger when measured over the Ru/i-Si-o catalyst as compared to the Ru/SiO2 catalyst. DFT analysis indicate that charged Ru surfaces can destabilize adsorbed CO2 molecules and adsorb and dissociate H such that it can readily react with CO2, thereby accelerating the Sabatier reaction. See full paper at: Energy & Environmental Science.
December 6th, 2018: CO2 Conversion and Corrosion: Mind the Gap
The community of scientists and engineers dedicated to the development of synthetic fuels made from CO2 is large and growing. From catalytic synthesis to reactor design, these researchers work on devising strategies to yield the most energy efficient and cost-effective CO2 conversion technologies. There exists, however, another community of experts also dedicated to working on CO2, albeit from a very different perspective: these are the scientists and engineers dedicated to the capture, purification, transportation and distribution of CO2 for either storage or enhanced oil recovery purposes. Their attention is largely focused on the important, and yet often forgotten corrosive nature of CO2 on processing equipment, containers, and pipelines made of carbon steel. Given the current trend, these seemingly disparate fields would greatly benefit by overcoming the CO2 communications gap, which appears to exist between scientists and engineers working on these problems. See full story at: Advanced Science News.
November 19th, 2018: Preventative Care of Our Planet – A Global Renewable Synthetic Fuels Roadmap
Synthetic fuels made using non-fossil renewable sources of energy, could make a significant contribution to achieving the 1.5 °C objective set out by the Paris Climate Agreement. While not widely recognised, technologies for making such synthetic fuels are in an advanced state of technological readiness; however, large-scale production will entail further development of several technologies, decision-making on where to locate different facilities, and the building of infrastructure to transport the fuels to where they are needed. A recent report put forth by Frontier Economics at the commission of the World Energy Council in Germany seeks to develop a dedicated roadmap for establishing a global renewable electricity to fuel industry. See full story at: Advanced Science News.
October 23rd, 2018: U of T Solar Fuels Group Joins Final of the Carbon XPRIZE
The University of Toronto Solar Fuels group has recently joined C4X, an NRG COSIA Carbon XPRIZE finalist, in their effort to create viable carbon dioxide utilization technologies in an effort to alleviate the effects of global warming caused by atmospheric greenhouse gases.
This new partnership brings together several large emitters and technology providers, enabling a clear path forward for validation of new carbon-reducing technologies on an industrial scale. Partners include:
- C4X Technologies Inc., led by Dr. Wayne Song (Toronto, ON)
- PERDC of Ford Motors Canada, led by Dr. Jimi Tjong (Windsor, ON)
- PolyBio Inc., led by Professor Mohini Sain from the Department of Chemical Engineering (Toronto, ON)
- The U of T Solar Fuels group, led by Professor Geoffrey Ozin from the Department of Chemistry (Toronto, ON)
- Walkerville Brewery, led by Neil Bishop
C4X is currently operating in Suzhou, China, and is planning to expand operations to Canada through this partnership.
The University of Toronto Solar Fuels group develops solar-driven technologies for the conversion of greenhouse gases like carbon dioxide into value-added chemicals and products. This opportunity to scale these technologies in a real-world setting is a major step forward in the path to commercialization of this work.
October 20th, 2018: Congratulation to Jinlong Gong for your paper in Angewandte Chemie!
Selectively targeting one high value-added chemical fuel, such as methanol, from CO2 reduction in aqueous solutions remains a grand challenge. By intentionally constructing a well-defined defined Cu/Cu2O interface, the binding strength of surface adsorbed H* and CO* intermediates could be balanced in a photoelectrochemical reduction of CO2 in aqueous solution, leading to methanol production with an impressive Faradaic efficiency of 53.6%. The full paper, entitled “Tuning Cu/Cu2O Interfaces for Reduction of Carbon Dioxide to Methanol in Aqueous Solutions”, can be found at Angewandte Chemie.
October 3rd, 2018: Human Intelligence and Experiential Learning in Materials Discovery
We have arguably reached a point in the evolution of materials chemistry where the discovery of a brand-new material or novel material property is rare. Although there will, of course, always be the occasional eureka moment, current materials research is mainly focused on the design of self-assembled material architectures that yield specific properties to satisfy the function required of an application. An inevitable question in today’s technological context, however, is the role of artificial intelligence in the materials research process. Can AI be trained to accomplish tasks and practice continual learning, intuition, and creativity, in a manner that matches or even supersedes human intelligence? See full story at: Advanced Science News.