R. Sharma, M. Carnoy, M. Ceccato, B. Borie, M. Plakhotnyuk
Atlant 3D,
Denmark
Keywords: direct atomic layer processing (DALP), waste reduction hydrogen evolution reaction (HER), ultra-low platinum loading, catalyst fabrication, solvent-free deposition, sustainable electrochemistry, remediation technologies, green manufacturing, circular materials design
Summary:
We demonstrate the use of Direct Atomic Layer Processing (DALP) as a transformative, material-efficient fabrication technique for noble metal catalysts relevant to waste reduction and environmental remediation technologies. Specifically, we apply DALP to deposit nanometer-thin platinum (Pt) films for the hydrogen evolution reaction (HER), a cornerstone electrochemical process in clean hydrogen generation. DALP is a direct-write, solvent-free, site-specific deposition method capable of forming ultra-thin, conformal metal layers with atomic precision, eliminating many of the waste streams and inefficiencies associated with conventional catalyst manufacturing. Traditional Pt catalyst fabrication—whether through wet-chemical synthesis of nanoparticles, sputtering, or ink deposition—often suffers from poor material utilization, overspray or binder loss, and requires significant chemical waste handling. In contrast, DALP enables patterned, additive-only growth of Pt films directly onto conductive substrates without masks, etching, or carrier solvents. This drastically reduces precursor waste, eliminates the need for multiple processing steps, and offers localized deposition with minimal overshoot or contamination. In this study, we use DALP to fabricate a series of Pt films ranging from 2 to 50 nm in thickness and evaluate them electrochemically in acidic conditions for HER performance. Notably, Pt films as thin as 30 nm—containing only ~64 µg cm⁻² of precious metal—achieve electrocatalytic performance comparable to bulk or commercial Pt/C systems that use over 1 mg cm⁻² of Pt. This represents a ~95% reduction in platinum usage without compromising functional performance, highlighting DALP's promise as a low-waste, high-efficiency deposition route for noble metals. Furthermore, DALP’s precision enables spatial control over catalyst deposition, allowing researchers and engineers to create patterned, gradient, or selectively activated surfaces. This is particularly useful for designing structured electrodes in water purification, wastewater treatment, and CO₂ or nitrate remediation systems where catalyst placement and material savings are critical. The ability to confine catalytic materials to where they are functionally needed reduces not only material consumption but also post-processing and recovery costs. By eliminating organic binders and solvents, DALP also simplifies end-of-life recovery of noble metals and reduces the generation of persistent chemical pollutants. The high-purity films produced are easier to recycle, enhancing circularity in electrode design. Future extensions of this platform may include the deposition of bimetallic catalysts, oxide shells, or functional multilayers—again without introducing wasteful intermediate steps. In summary, DALP enables ultra-low-waste fabrication of high-performance catalytic electrodes, making it highly relevant for sustainable hydrogen production and environmental remediation technologies. This work demonstrates a path forward for precision catalyst engineering that aligns with green chemistry and circular economy principles—delivering both performance and sustainability in next-generation electrochemical systems.