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Photothermal synergistic CO 2 reforming of CH 4 (CRM) is a promising avenue to convert the greenhouse gases (CO 2 and CH 4) into valuable chemicals and store the abundant clean solar energy into chemical energy simultaneously. Developing photothermal catalysts that could drive CRM efficiently at low temperatures remains as a challenge. In the present study, Nb 2 O 5 supported group VIII metal catalysts (M/Nb 2 O 5) were synthesized, with the typical catalyst Rh/Nb 2 O 5 recording a CO 2 conversion rate of 50.6 mmol g Rh −1 min−1 in CRM at 500 °C under visible light irradiation, about double fold higher than that achieved under the thermal-driven reaction condition. Mechanism study disclosed that oxygen vacancy was generated in situ over M/Nb 2 O 5 under the CRM reaction atmosphere. The oxygen vacancy promoted CO 2 adsorption and enhanced the light harvesting capacities of M/Nb 2 O 5 catalysts, which ultimately boosted their activities in photothermal CRM. This study provides a promising pathway for the rational design of efficient catalysts by tailoring the properties of the catalysts under the reaction atmosphere. • Oxygen vacancies could be generated in situ over M/Nb 2 O 5 catalysts in CRM. • Oxygen vacancy promoted catalyst light harvesting capacity and the activation of CO 2. • M/Nb 2 O 5 catalysts recorded a higher performance in CRM with visible light assistance. [ABSTRACT FROM AUTHOR]

• The flexible re-energizing time for transmission lines is considered in GSUS model. • Some 0–1 variables are employed to formulate constraints as linear constraints. • Serial restoration requirement is modeled as mixed integer linear constraints. • Transient frequency requirement is modeled as mixed integer linear constraints. During power system restoration, the planning of the generator start-up sequence (GSUS) can significantly affect the restoration efficiency. However, a GSUS optimization model based on mixed integer linear programming (MILP) cannot satisfy the need for flexible re-energizing times of transmission lines and the serial restoration of generators. To solve this issue, a new MILP-based GSUS optimization model is proposed in this paper that can generate a serial GSUS scheme with flexible re-energizing times of transmission lines. The requirements of flexible re-energizing times of transmission lines and the serial restoration of the generators are formulated as restoration time constraints for the transmission lines, start-up time constraints for the buses on the restoration paths, and a serial restoration constraint, which are transformed into mixed integer linear constraints by means of auxiliary binary (0–1) decision variables. Meanwhile, the restart time constraints of the generators and the transient frequency requirements are modeled as mixed integer linear constraints. Finally, the performance of the proposed method is verified on the IEEE 39-bus system. [ABSTRACT FROM AUTHOR]