Fusion bonding of copper and silicon at -70 °C by electrochemistry

Chien, Po Yen; Cheng, Lin; Liu, Cheng Ying; Li, Jhong En; Lee, T. H.

doi:10.1016/j.actamat.2020.116486

“…[42][43][44] Those reactions allow the formation of both Si 0 (defect) and Cu 0 at the CuÀ Si interface with the presence of photogenerated electron caused by the illumination of Si. Accordingly, this mechanism facilitates the dynamic addition/elimination of lattice oxygen on both Cu nanocrystals and BSi surface to generate additional structural defects, which could further enhance atomic mobility and promote the mutual interdiffusion between Cu and Si atoms through an interstitial mechanism, [45][46] resulting in the formation of an irreversible silicide (i.e., Cu 3 Si phase).…”

Section: Correlation Between Proposed Atomic Interdiffusion and Produ...mentioning

confidence: 99%

Light‐Induced Dynamic Activation of Copper/Silicon Interface for Highly Selective Carbon Dioxide Reduction

Wang,

Lai,

Lin

et al. 2024

Angewandte Chemie

0

View full text Add to dashboard Cite

Numerous studies have shown a fact that phase transformation and/or reconstruction are likely to occur and play crucial roles in electrochemical scenarios. Nevertheless, a decisive factor (such as facet, phase etc.) behind the diverse photoelectrochemical activity and selectivity of various copper/silicon photoelectrodes is still largely debated and missing in the community, especially for possibly dynamic behaviors of metal catalyst/semiconductor interface. Herein, through in situ X‐ray absorption spectroscopy and transmission electron microscope, a model system of Cu nanocrystals with well‐defined facets on black p‐type silicon (BSi) is demonstrated to unprecedentedly reveal the dynamic phase transformation of forming irreversible silicide at Cu nanocrystal‐BSi interface, which is validated to originate from the atomic interdiffusion between Cu and Si driven by light‐induced dynamic activation process. The presence of in situ formed silicide can significantly enhance photovoltage and deliver a record‐high onset potential above ‐0.4 V versus reversible reference electrode (RHE) for photoelectrochemical CH4 production. Significantly, the adaptive junction at Cu/Si interface is activated by an expansion of interatomic Cu‐Cu distance, which efficiently restricts the C‐C coupling pathway but strengthens the bonding with key intermediate of *CHO for CH4 yield, resulting in a remarkable 16‐fold improvement in the product ratio of CH4/C2 products.

show abstract

“…To the day, a common strategy to achieve low-temperature/cryogenic conditions remains to immerse conventional test cells in slush/cooling baths consisting of dry ice mixed with organic solvents [15][16][17], allowing for temperatures as low as À 78 °C [12,13,18]. Drawbacks of such immersion techniques are evident: An accurate temperature conditioning/regulation of the electrolyte solution inside the test cell is missing, particularly problematic during long-term measurement sessions [13,17]. As temperatures cannot be changed intentionally, a variation requires discontinuous manipulations of the bath [19,20].…”

mentioning

confidence: 99%

Design of a flexible but robust setup for temperature‐dependent electrochemistry down to cryogenic temperatures

Weber

¹

,

Fink

²

,

Schönfeld

³

et al. 2023

Electroanalysis

0

View full text Add to dashboard Cite

Electrochemistry and its analytics are essential in a variety of scientific and technological fields where properties related to reduction‐oxidation reactions, so‐called redox properties, are to be explored. While methodological standards for experiments are well established at room temperature, this is still untrue at sub‐zero/cryogenic temperatures, the conditions required for the survey of (ultra−)rapid processes and their intermediates. Problems due to “hand‐waving” temperature regulation/conditioning and common usage of pseudo‐reference electrodes renders cryo‐electrochemistry a great challenge. Herein, we describe a robust setup for performing reliable cryo‐electrochemical experiments down to −80 °C. It combines highly stable but flexible temperature conditioning with gas‐tight sealing of the electrochemical cell setup. Modification of a commercial palladium hydride reference electrode (PdH RE) allows for rapid temperature cycling under cryogenic conditions in aprotic organic solvents. Validation of the setup with the well‐known Ferrocene|Ferrocenium (Fc|Fc+) redox couple gave good compliance with literature data at room temperature in a range of organic solvent‐based electrolytes. Evaluation of temperature‐dependent diffusion kinetic parameters, such as diffusion coefficients (D) and diffusional activation energies (Ea,D) from CVs at multiple potential scan‐rates and temperature levels emphasize the reliability of the presented cryo‐electrochemical setup.

show abstract

Light‐Induced Dynamic Activation of Copper/Silicon Interface for Highly Selective Carbon Dioxide Reduction

Wang,

Lai,

Lin

et al. 2024

Angew Chem Int Ed

1

0

View full text Add to dashboard Cite

Numerous studies have shown a fact that phase transformation and/or reconstruction are likely to occur and play crucial roles in electrochemical scenarios. Nevertheless, a decisive factor (such as facet, phase etc.) behind the diverse photoelectrochemical activity and selectivity of various copper/silicon photoelectrodes is still largely debated and missing in the community, especially for possibly dynamic behaviors of metal catalyst/semiconductor interface. Herein, through in situ X‐ray absorption spectroscopy and transmission electron microscope, a model system of Cu nanocrystals with well‐defined facets on black p‐type silicon (BSi) is demonstrated to unprecedentedly reveal the dynamic phase transformation of forming irreversible silicide at Cu nanocrystal‐BSi interface, which is validated to originate from the atomic interdiffusion between Cu and Si driven by light‐induced dynamic activation process. The presence of in situ formed silicide can significantly enhance photovoltage and deliver a record‐high onset potential above ‐0.4 V versus reversible reference electrode (RHE) for photoelectrochemical CH4 production. Significantly, the adaptive junction at Cu/Si interface is activated by an expansion of interatomic Cu‐Cu distance, which efficiently restricts the C‐C coupling pathway but strengthens the bonding with key intermediate of *CHO for CH4 yield, resulting in a remarkable 16‐fold improvement in the product ratio of CH4/C2 products.

show abstract

Fusion bonding of copper and silicon at -70 °C by electrochemistry

Cited by 5 publications

References 18 publications

Light‐Induced Dynamic Activation of Copper/Silicon Interface for Highly Selective Carbon Dioxide Reduction

Light‐Induced Dynamic Activation of Copper/Silicon Interface for Highly Selective Carbon Dioxide Reduction

Design of a flexible but robust setup for temperature‐dependent electrochemistry down to cryogenic temperatures

Light‐Induced Dynamic Activation of Copper/Silicon Interface for Highly Selective Carbon Dioxide Reduction

Contact Info

Product

Resources

About