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Phase change materials (PCMs) are recognized as a promising passive energy retrofit technology for existing buildings, as they are applied to the internal and external surfaces of the building with less impact on the original structure. However, the effectiveness of PCMs varies from region to region. Taking the Central Plains of China as an example, this paper investigated the effect of phase change temperature and material thickness variation on the energy efficiency of PCM when it was arranged on 14 placements including furniture through EnergyPlus (E+). And further explored the applicability of coupling PCMs with natural ventilation (NV). The results showed that: for the Central Plains of China, PCMs arranged on the internal surface of building roofs were optimal, and the reduction rate of uncomfortable degree hours could reach 38%, 26%, 24% and 40% after integrating PCMs into the roof, floor, external wall and furniture. The uncomfortable degree hour reduction rate per unit mass of PCM was 0.052%/kg for the roof, and the value of furniture was very close to the external wall and floor, which achieved 0.033%/kg. In addition, the coupling of PCM with NV improved the energy efficiency of PCM by more than twice. [ABSTRACT FROM AUTHOR]

• Exploring cooling behaviors beyond air conditioning in residential demand response. • Testing the effect of cooling behaviors on thermal comfort during demand response. • Identifying inaccuracy of prevalent thermal comfort models for demand response. • Developing more precise thermal comfort models for residential demand response. During periods of electricity demand response (DR) in residential buildings, inhabitants frequently engage in supplementary cooling behaviors, extending beyond the utilization of air conditioning (AC). However, the prevalent thermal comfort models, namely the Predicted Mean Vote (PMV) and Temperature Range Method (TRM), which are typically employed during DR periods, are designed for stable environments and do not consider the impact of these additional cooling behaviors. This study aims to develop novel thermal comfort models that more accurately reflect these behaviors during residential DR periods. The initial stage of the study involved a questionnaire survey conducted among residents in Zhengzhou, China, to investigate the AC usage patterns and additional cooling behaviors. Subsequently, typical AC DR strategies, which include increasing indoor temperature set points and turning off AC, along with the three most comment additional cooling behaviors, namely utilizing an electric fan, reducing clothing and consuming cold beverages, were examined through multi-scenario experiments. The findings from these experiments facilitated the development of two novel models: the PMV-DR model, indicative of the thermal comfort level, and the TRM-DR model, representative of the thermal comfort acceptance rate (AR) during the DR period. When compared with the traditional PMV and TRM models, these newly proposed models demonstrated greater consistency with the experimental results. As a result, these models could serve as the basis for thermal comfort evaluations during residential DR periods in the Zhengzhou region. Furthermore, they could provide a methodological benchmark for other geographical locales. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Pt/Bi 2 O 3 interfaces undergo structural reconstruction during CV process and form highly dispersed Bi0 species on the surface of Pt aerogel. • Higher MOR activity in alkaline media was obtained for Bi0 decorated Pt aerogel. • The reaction kinetics is investigated by In-suit FTIR measurement and DFT calculations. Improving the activity and stability of electrocatalysts for methanol oxidation reaction (MOR) is key important for the large-scale application of direct methanol fuel cells (DMFCs). Herein, we provide a novel scheme to firstly build Bi-decorated Pt aerogel through the structural reconstruction of Pt/Bi 2 O 3 interface, which demonstrates an excellent mass activity of 7.99 A mg-1 Pt in MOR (8-fold higher than that of commercial Pt/C). Experimental results show that the synergistic effect between Bi0 species and Pt aerogel is the major cause of the improvement of the catalytic activity. In-suit Fourier transform infrared (FTIR) Spectroscopy results indicated that the generation and transformation of HCOO– intermediate are accelerated. Density functional theory (DFT) calculations indicate that the decorated Bi enhances the adsorption of OH species on the adjacent Pt site, which can facilitate the dehydrogenation of methanol and the removal of poisonous CO species. Thus, the electro-catalytic performance can be improved. This strategy can be extended to construct other types of interfaces, which may open new routes for the synthesis of highly efficient electrocatalysts. [ABSTRACT FROM AUTHOR]