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This content will become publicly available on June 26, 2026

Title: Spontaneous formation of urea from carbon dioxide and ammonia in aqueous droplets
Urea is a key molecule in the search for the origin of life and a basic chemical produced in large quantities by industry. Its formation from ammonia and carbon dioxide requires either high pressures and temperatures or, under milder conditions, catalysts or additional reagents. In this study, we observed the spontaneous formation of urea under ambient conditions from ammonia and carbon dioxide in the surface layer of aqueous droplets. Single, optically trapped droplets were probed by using Raman bands as markers. We found the surface layer to act like a microscopic flow reactor, with chemical gradients providing access to unconventional reaction pathways. This observation revealed a general mechanistic scheme for distinctive droplet chemistry. Interfacial chemistry is a possible nonenergetic route for urea formation under prebiotic conditions.  more » « less
Award ID(s):
1940456
PAR ID:
10636406
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Science
Date Published:
Journal Name:
Science
Volume:
388
Issue:
6754
ISSN:
0036-8075
Page Range / eLocation ID:
1426 to 1430
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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