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Venture Builder Helping People Adapt to Climate Change



Name: Walter Johnsen (he/him)

PhD: Inorganic Chemistry, University of Pennsylvania, 2023



What was your main area of research?

I studied how known catalysts transform carbon dioxide, water, and electricity into multi-carbon fuels and chemicals. To understand critical steps - such as the first carbon-carbon bond forming step, I developed non-catalytic models of the active catalyst, measured relevant rates, and calculated key binding energies. Ultimately, this research will inform the design of the next generation of CO2 reduction catalysts. 



What is your current job?

I am a Venture Science Associate at Marble in Paris, France 🇫🇷.


At Marble, we build climate technology companies that have the potential to remove 1 gigaton of CO2 equivalents or help > 100 million people adapt to a changing world. In my job, I scope sectors to find under-utilized technologies, collaborate with great entrepreneurs and scientists to develop the core innovations underlying their companies, and support our funded portfolio companies with their design of experiments. 


First, I love the breadth of technical projects I work on through this role. Currently, I'm leading our venture building efforts on new technologies for air conditioning, CO2 electrolysis, and silicon refining. I am constantly learning about new innovations and technology landscapes. 


Second, this role is truly outward-facing and involves regular calls with professors, start-up executives, industry professionals, venture capitalists / investors, and more! In fact, as I'm writing this, I'm on the train to Barcelona to attend a battery materials conference, where I hope to learn more about innovations in that sector.



How did you find this position? What were the career steps you took to get to where you are now? 

I found this job through word of mouth & the CTVC newsletter.


PhD Graduate ➡️ Venture Builder



Why did you decide to not pursue a career in academia? 

I loved graduate school and had a great relationship with my PhD advisors. But by the end, I felt siloed - only focusing on one problem of one technology. 


I recognized that after grad school, I wanted a role where I could learn about more technologies and be exposed to a diverse set of problems.


I asked myself, "what organizations and entities have large technology portfolios". To me the answer was the Department of Energy and venture firms. 


Ultimately, I chose my position at Marble for a few reasons: (1) through building companies, I would work with technology stacks for a long time and more fully understand key problems; (2) I would be intimately involved in commercializing science; and finally (3) I was excited by the prospect of moving to Europe and building a professional network here. 



What advice do you have for someone getting their PhD and looking to pursue a career outside of academia?

  1. Explore extracurriculars in graduate school that align with your interests! During graduate school, I knew I was passionate about energy technologies. I sought to build a more comprehensive exposure around energy through advising a green bank in Philadelphia, researching with an energy think tank, and studying at 2 DOE national labs. By following my interests, I unintentionally created a strong narrative about why I was the person to work in an energy-centered role. 

  2. Think seriously about the career you want after grad school at least 18 months before you graduate. Then, take a look at the LinkedIns and resumes of individuals in those roles. Ask "what badges and experiences do they have?". And then see if you can get them too!

  3. It's okay to not have a plan. It's not okay to sit idle. On a similar note, I recommend constantly trying new things professionally and asking questions.

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