Structure induced electron transfer in crumpled graphene oxide enables efficient adsorption reduction synergistic...

The recovery of silver ions (Ag⁺) from wastewater is of great importance for both resource sustainability and environmental protection. Conventional carbon based adsorbents generally rely on surface area and oxygen containing functional groups for metal ion capture, yet the role of morphology induced electronic regulation in promoting interfacial electron transfer remains poorly understood. Herein, crumpled graphene oxide (CGO) with ridge like folded structures was employed as a model material to elucidate the relationship between structural characteristics, electron transfer, and Ag⁺ recovery performance. Activated carbon (AC), multi-walled carbon nanotubes (MWCNT), and reduced graphene oxide (rGO) were selected as reference materials for systematic comparison. Despite possessing the lowest specific surface area among the investigated carbon materials, CGO exhibited the highest Ag⁺ recovery capacity of 83.39 mg g^-1, excellent recovery performance under trace concentration conditions, remarkable selectivity in multimetal systems, and good cycling stability. Characterization combined with Raman spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and DFT calculations revealed that Ag⁺ was preferentially reduced and deposited within the ridge like folded regions of CGO through an electron transfer driven reduction process. The ridge like crumpled architecture induces localized strain, redistributes π electron density, and creates electronically active regions that facilitate interfacial electron transfer, thereby promoting the in-situ reduction of Ag⁺ into metallic Ag. This work establishes a clear structure electron transfer recovery relationship for carbon materials and demonstrates that morphology induced electronic regulation provides an effective strategy for designing advanced carbon materials for sustainable precious metal recovery.