Research
STEPS research is organized by Themes, length-scale groupings in which researchers pursue closely related research questions, promote interactions on highly associated research activities, and drive overall forward momentum.

Themes
Theme 1 (Materials Scale) generates new fundamental knowledge about phosphorus capture at atomic and molecular scales using discovery-driven approaches (i.e., biological inspiration, chemical analytics). Integrated with Materials Informatics (MI), Theme 1 accelerates the development of novel capabilities to promote the facile transformation of organic and inorganic phosphorus and enable the efficient capture and recovery of phosphate.
Theme 2 (Human-Technology Scale) implements materials and technologies from Theme 1 in both aqueous suspensions (e.g., surface water and wastewater) and the plant-soil-microbial system by using laboratory, greenhouse, and field-scale techniques. Theme 2 applies state-of-the-art scientific approaches including nanoscale spectroscopic characterization of phosphate speciation in soils, novel sensor development to improve tracking of phosphorus in soils, genome-wide approaches for selecting and engineering crop systems with enhanced phosphorus utilization, and development of next-generation, plant-responsive fertilizers.
Theme 3 (Regional and Global Scale) identifies intervention portfolios (e.g., innovative technologies, best management practices) that enable the realization of the 25-in-25 vision and are resilient to socio-economic, policy, and environmental change, using integrated modeling at global, regional, and local scales and social network analysis. Theme 2 data about the flow and management of phosphorus as a function of space and time (e.g., through urban, aquatic, and agricultural systems) guide research prioritization in Themes 1 and 2.
A Convergence Informatics (CI) research initiative provides data-science-driven guidance for the design of novel and effective materials, technologies, and strategies for phosphorus capture, decomposition, and modification to realize the opportunities presented by Theme integration. CI builds upon an MI-based approach in which process-structure-properties-performance relations are designed by analyzing large materials data sets with machine learning algorithms.
The STEPS convergence research strategy, drawing from the fields of Science of Team Science as well as Integration and Implementation Science, utilizes evidence-based approaches to assimilate emerging knowledge and co-refine research questions through strategically designed interactions and processes. Convergence research strategies create efficiencies at integrating research across 17 orders of magnitude in length scale. Convergence boundary objects (data, phosphorus flow diagrams, and language mapping) serve as tangible and conceptual anchors, linking specific research contributions across STEPS disciplines and length scales and allowing the researchers to contextualize individual contributions to a highly complex problem. An example of one of these, a phosphorus flow diagram, is shown below. Specific geographical sites or Triple-Bottom-Line Scenarios that represent urban, agricultural, and aquatic systems provide technological constraints, potential impact scenarios, and connection to unique types of stakeholders in phosphorus sustainability.

Projects
Theme 1
1.1 Chemical and Biological Transformations of Non-Reactive Phosphorus
Project PI: Brooke Mayer
Co-PIs: Doug Call, Paul Westerhoff
1.2 Standardizing & Advancing Phosphorus Analytics
Project PI: Paul Westerhoff
Co-PIs: Jacob Jones, Doug Call
1.3 Bio-Inspired Phosphorus Removal and Recovery
Project PI: Brooke Mayer
Co-PIs: Yara Yingling, Eric McLamore
1.4 High-Throughput Screening of Phosphate Adsorption in Polymer Brushes
Project PI: Jan Genzer
Co-PIs: Marty Lail, Sherine Obare, Yara Yingling
1.5 Metal Cations for Phosphorus Recovery
Project PI: Chris Muhich
Co-PIs: Jacob Jones, Detlef Knappe, Paul Westerhoff
1.6 Biomimetic Phosphate Sorbents via Chemical Modification of 2D Materials
Project PI: Wei Gao
Theme 2
2.1 Human Urine as Boundary Object for Advancing Phosphorus Recovery
Project PI: Treavor Boyer
Co-PIs: Doug Call, Anna-Maria Marshall
2.2 Characterizing Phosphorus After Anaerobic Treatment of High-Strength Organic Waste Streams
Project PI: Bruce Rittmann
Co-PIs: Sherine Obare, Doug Call, Joshua Boltz
2.3 Developing Phosphite as a Sustainable, Next Generation Fertilizer
Project PI: Owen Duckworth
Co-PIs: Doug Call, Chris Muhich
2.4 Understanding of the genetic mechanisms involved in the regulation of plant phosphorus use efficiency
Project PI: Rubén Rellán Álvarez
Co-PI: Ross Sozzani
2.5 Controlling and Utilizing Legacy Phosphorus in Soils
Project PI: Luke Gatiboni
Co-PIs: Jango Bhadha, Owen Duckworth
2.6 Exploring stimulus-response nanobrush materials for phosphorus sensing
Project PI: Eric McLamore
Co-PIs: Sherine Obare, Jango Bhadha
Theme 3
3.1 National Phosphorus Budget and Mapping Phase I
Project PI: Dan Obenour
Co-PIs: Natalie Nelson, Owen Duckworth, Paul Westerhoff, Rebecca Muenich
3.2 Establishing Baseline Data and Tools for Simulating Phosphorus Flows at the TBLs
Project PI: Natalie Nelson
Co-PIs: Elise Morrison, Rebecca Muenich, Sandra Guzman
3.3 Evaluating Stakeholder Perceptions, Needs, and Networks in STEPS Research
Project PI: Khara Grieger
Co-PI: Anna-Maria Marshall
3.4 Adoption and Diffusion of Innovation: Case Studies of STEPS Technologies
Project PI: Anna-Maria Marshall
Co-PIs: Khara Grieger
3.5 Systems Modeling, Decision Support, and Roadmapping to Achieve 25-in-25
Project PI: Justin Baker
Co-PIs: Jordan Kern, Rebecca Muenich, Cary Strickland
Convergence Informatics & Other Research
4.1 Convergence Informatics I: Gathering and Fusing Data
Project PI: Yara Yingling
Co-PIs: Rada Chirkova, Cranos Williams
4.2 Convergence Science Education Research
Project PI: Gail Jones
4.3 Developing Technical and Convergence Educational Resources
Project PI: John Classen