This study investigates the carbon deposition on copper (Cu) catalysts during electrochemical CO₂ reduction (CO₂RR) and proposes strategies to mitigate this issue. The research reveals that carbon deposition occurs on Cu electrodes during CO₂RR, particularly at potentials between -0.8 V and -1.5 V versus RHE, with the most severe deposition at -1.2 V. The carbon forms as a result of the desorption of the *CO intermediate, which is crucial for methane (CH₄) formation. The study shows a strong correlation between carbon deposition and CH₄ production, with higher carbon deposition under conditions favoring CH₄ formation. The deposited carbon blocks active sites on the electrode, leading to rapid degradation of catalytic performance. The study also demonstrates that increasing the roughness of the electrode and the pH of the electrolyte can mitigate carbon deposition. Rougher electrodes and higher pH environments reduce carbon deposition by altering the reaction pathways and minimizing the formation of carbon intermediates. The research further shows that carbon deposition is more pronounced in acidic electrolytes due to the formation of *COH and *C intermediates. The study provides insights into the formation mechanism of carbon deposition, linking it to CH₄ production and offering strategies to avoid carbon accumulation for more stable and efficient catalysts. The findings highlight the importance of understanding and controlling carbon deposition to enhance the stability and efficiency of Cu-based catalysts for CO₂RR. By adjusting electrode roughness and electrolyte pH, it is possible to shift the reaction pathway from CH₄ formation to the production of multicarbon products, thereby reducing carbon deposition and improving catalytic performance. The study contributes to the development of more stable and efficient catalysts for CO₂ electrolysis, which is crucial for addressing environmental challenges related to carbon dioxide.This study investigates the carbon deposition on copper (Cu) catalysts during electrochemical CO₂ reduction (CO₂RR) and proposes strategies to mitigate this issue. The research reveals that carbon deposition occurs on Cu electrodes during CO₂RR, particularly at potentials between -0.8 V and -1.5 V versus RHE, with the most severe deposition at -1.2 V. The carbon forms as a result of the desorption of the *CO intermediate, which is crucial for methane (CH₄) formation. The study shows a strong correlation between carbon deposition and CH₄ production, with higher carbon deposition under conditions favoring CH₄ formation. The deposited carbon blocks active sites on the electrode, leading to rapid degradation of catalytic performance. The study also demonstrates that increasing the roughness of the electrode and the pH of the electrolyte can mitigate carbon deposition. Rougher electrodes and higher pH environments reduce carbon deposition by altering the reaction pathways and minimizing the formation of carbon intermediates. The research further shows that carbon deposition is more pronounced in acidic electrolytes due to the formation of *COH and *C intermediates. The study provides insights into the formation mechanism of carbon deposition, linking it to CH₄ production and offering strategies to avoid carbon accumulation for more stable and efficient catalysts. The findings highlight the importance of understanding and controlling carbon deposition to enhance the stability and efficiency of Cu-based catalysts for CO₂RR. By adjusting electrode roughness and electrolyte pH, it is possible to shift the reaction pathway from CH₄ formation to the production of multicarbon products, thereby reducing carbon deposition and improving catalytic performance. The study contributes to the development of more stable and efficient catalysts for CO₂ electrolysis, which is crucial for addressing environmental challenges related to carbon dioxide.