Abnormal Magnetic Behaviors in Unique Square alpha-MnO2 Nanotubes

TL;DR

This study investigates the unusual magnetic behaviors of square alpha-MnO2 nanotubes synthesized via a hydrothermal method, revealing large orbital moments and unique magnetic phenomena due to nanoscale structural engineering.

Contribution

It reports the first observation of abnormal magnetic phenomena in square alpha-MnO2 nanotubes and links these behaviors to nanoscale structural effects and orbital moments.

Findings

Observation of abnormal magnetization versus temperature behavior

Large and abnormal horizontal shift in magnetization hysteresis loops

Linking magnetic anomalies to large unfrozen orbital moments

Abstract

Systematic magnetic measurements have been performed in unique$\alpha - MnO_2$ square nanotubes synthesized by a facile hydrothermal method with microwave-assisted procedures. Unusual magnetic phenomena (abnormal magnetization verse temperature (M - T) behaviour, large and abnormal magnetization hysteresis loop horizontal shift (HHS) verse cooling field (HFC) behaviours (HHS - HFC) has been observed in these square nanotubes. These suggest the observation of large unfrozen orbital moment which also is the micro -original of observed large and abnormal horizontal shift (HHS). The findings demonstrated that engineering layered structures in nanoscale would create many unique nanostructures and unusual physicochemical behaviours.