arXiv subjects

Chuhongxu Chen

Publications and source records attributed to Chuhongxu Chen.

3 recordsLinked to original sources

arXiv2025

Rapid fabrication of clean van der Waals nanochannels using Mask and Stack method

Two-dimensional (2D) nanochannels have emerged as a pivotal platform for exploring nanoscale hydrodynamics and electrokinetics. Conventional fabrication methods to make nanochannels often introduce polymer contamination and require lengthy processing, limiting device performance and scalability. Here we introduce the Mask & Stack method, employing silicon nitride stencil mask combined with dry transfer stacking to rapidly fabricate ultraclean vdW nanochannels within hours. This polymer-free approach preserves pristine interfaces, confirmed by atomic force microscopy and Raman spectroscopy, and yields nanochannel devices exhibiting reproducible ionic transport and long-term stability. The streamlined process is compatible with diverse 2D materials and promising for upscale production. Our method advances the fabrication of nanofluidic and 2D heterostructure devices, facilitating applications in quantum transport, photonics, energy harvesting, and sensing technologies requiring high-throughput, contamination-free heterostructure architectures.

cond-mat.mes-hall↗

arXiv2025

Silver Electrodeposition from Ag/AgCl Electrodes: Implications for Nanoscience

With the advancement of nanoscience, silver/silver chloride (Ag/AgCl) electrodes have become widely utilised in microscale and nanoscale fluidic experiments, because of their stability. However, our findings reveal that the dissolution of AgCl from the electrode in \ch{Cl-}-rich solutions can lead to significant silver contamination, through the formation of silver complexes, \ch{[AgCl_{n+1}]^{n-}}. We demonstrate the electrodeposition of silver particles on graphene in KCl aqueous solution, with AgCl dissolution from the electrode as the sole source of silver. This unexpected electrodeposition process offers a more plausible interpretation of the recently reported ``ionic flow-induced current in graphene''. That is, the measured electronic current in graphene is due to the electrodeposition of silver, challenging the previously claimed ``ionic Coulomb drag''. More caution is called for when using Ag/AgCl electrodes in microfluidic, and especially nanofluidic systems, because AgCl dissolution should not be neglected.

cond-mat.mes-hall↗

arXiv2023

Synthesis and characterisation of LK-99

Recently, two arXiv preprints (arXiv:2307.12008, arXiv:2307.12037) reported signatures of superconductivity above room temperature (SART) and at ambient pressure, striking worldwide experimental research efforts in replicating the results3-6, as well as theoretical attempts to explain the purported superconductivity7-11. The material of interest has chemical formula Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O, where $x \approx 1$, and was named by the authors as LK-99. It belongs to lead apatite family, and was synthesised from two precursors, lanarkite (PbSO$_4\cdot$PbO) and copper phosphide (Cu$_3$P). Here we performed a systematic study on LK-99, starting from solid-state synthesis, followed by characterisation and transport measurements. We did not observe any signatures of superconductivity in our samples of LK-99.

cond-mat.supr-con↗