The development of highly active and durable catalysts for electrochemical reduction of CO2 (ERC) to CH4 in aqueous media is an efficient and environmentally friendly solution to address global problems in energy and sustainability. In this work, an electrocatalyst consisting of single Zn atoms supported on microporous N-doped carbon was designed to enable multielectron transfer for catalyzing ERC to CH4 in 1 M KHCO3 solution. This catalyst exhibits a high Faradaic efficiency (FE) of 85%, a partial current density of −31.8 mA cm–2 at a potential of −1.8 V versus saturated calomel electrode, and remarkable stability, with neither an obvious current drop nor large FE fluctuation observed during 35 h of ERC, indicating a far superior performance than that of dominant Cu-based catalysts for ERC to CH4. Theoretical calculations reveal that single Zn atoms largely block CO generation and instead facilitate the production of CH4.

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The dynamic thermal performance of radiant terminal plays an important role in the design and control of radiant cooling system, which is shown as the dynamic thermal response of radiant floor system (RFS) under imposed control. In this paper, the field measurement method was used to study the dynamic thermal response of RFS. The RFS was activated in summer and the supply water temperature was regulated in winter to make dynamic change of thermal performance. The floor surface temperature was selected as the characteristic parameter to describe the dynamic heat transfer performance of the system, and response time τ95 and time constant τ63 were used to quantify the dynamic thermal response. The maximum τ95 was 13.5 h and τ95/τ63 was greater than or equal to 2 in the cooling mode, while τ95 and τ63 were both less than 10 h and τ95/τ63 was 1.6 in the heating mode. As a result, there was no significant lessening of temperature change rate, and the thermal response of RFS was faster under intermittent control of supply water temperature in winter. Therefore, the study aims at providing reference for making intermittent control strategy by using the dynamic thermal performance of radiant system.