[Objective

]

Manganese-based metal oxides have attracted widespread attention in high-temperature thermochemical systems due to their prominent advantages such as low cost

non-toxicity

and excellent reactivity with air

making them one of the most promising materials for next-generation solar thermal power generation and thermochemical energy storage technologies. However

single manganese-based metal oxide systems still face significant technical challenges in practical high-temperature applications: they are prone to sintering under longterm high-temperature conditions

which leads to a sharp decline in specific surface area and active sites

further resulting in reduced reaction stability and reversibility after multiple thermal cycles. Meanwhile

in next-generation sol

ar thermal power generation technology

high-temperature thermochemical particles have become a research focus because of their good fluidity

which facilitates efficient heat absorption and heat exchange between systems. Unfortunately

these particles often suffer from severe wear and consumption during cyclic operation

leading to a short replacement cycle and high operation and maintenance costs

which greatly limits their large-scale industrial application. [Methods

]

To address these key technical bottlenecks and promote the practical application of manganese-based metal oxide particles in high-temperature thermochemical systems

this study focuses on optimizing the comprehensive performance of(Mn

0.8

Fe

0.2

)_2O

3

composite metal oxide particles through modification. Specifically

manganese silicate was selected as the modifier to prepare modified(Mn

0.8

Fe

0.2

)_2O

3

composite metal oxide particles by the extrusion-spheronization process. To systematically evaluate the performance of the prepared particles

a three-chamber wear device

which can simulate the actual service environment of particles in solar concentrating and heat collecting systems and accurately reflect the wear degree during cyclic operation

was used to test the wear resistance. In addition

relevant analytical characterization methods were employed to comprehensively assess the reaction characteristics

cycle stability

and microstructural changes of the particles before and after modification. [Results

]

The experimental results demonstrate that manganese silicate doping modification can significantly improve the comprehensive performance of(Mn

0.8

Fe

0.2

)_2O

3

composite metal oxide particles: compared with the unmodified manganese-iron particles

the reaction reversibility of the modified particles is increased by 22%

which effectively solves the problem of reduced reaction reversibility caused by sintering; the wear resistance is increased by about 50

%

which greatly reduces the wear and consumption of particles during cyclic operation and extends their service life. Furthermore

based on the conversion factor derived from experimental data

the replenishment amount of particles during the long-term service process of the solar concentrating and heat collecting system was quantitatively calculated

providing a reliable theoretical basis for the cost control and stable operation of the system. [Conclusion

]

In conclusion

manganese silicate doping modification is an effective method to improve the key properties of(Mn

0.8

Fe

0.2

)_2O

3

composite metal oxide particles. It can effectively alleviate the sintering phenomenon

enhance wear resistance and cycle reaction stability

and solve the core defects of traditional manganese-based metal oxide particles in hightemperature thermochemical systems. This modification strategy not only improves the applicability and economy of the particles in next-generation solar thermal power generation technology but also lays a solid foundation for the research

development

and industrial application of low-cost

high-performance high-temperature thermochemical energy storage materials.