Study on performance of a full spectrum solar-driven hydrogen production system using Ag@SiO2-Au blended nanofluid filters

The integration of photovoltaic (PV) water electrolysis and medium-temperature thermochemical reactions with nanofluid filters presents a promising prospect for efficiently converting the complete spectrum of solar energy into hydrogen. However, the behavior of nanofluid in hydrogen production systems has yet to be thoroughly investigated in previous studies. In this regard, the current study introduces an innovative approach by incorporating Ag@SiO2-Au blended nanofluid filters into a concentrating photovoltaic/thermal (CPV/T) system. The system is further coupled with a proton exchange membrane (PEM) electrolyzer and a methanol steam reforming (MSR) system. The nanofluid filter is optimized to properly disintegrate the incident sunlight to drive PEM and MSR systems. This synergistic design enables the efficient sequential utilization of the complete solar spectrum, culminating in the storage of solar energy in the form of hydrogen. A comprehensive investigation is conducted by establishing models of CPV/T, PEM and MSR to examine the performance of the integrated system. The results demonstrate the significant promise of the blended nanofluid in facilitating a solar-driven hydrogen production system across the entire spectrum. Through optimization of nanofluid, the optimum nanofluid exhibits the capacity to maintain the system electrical efficiency at a minimum of 7.23%. This underscores the effective harnessing of high-grade solar energy. Based on GaAs solar cell, the solar-to-hydrogen efficiency (44.75%) of the system is impressive, in which 34.46% is the efficiency of solar energy electricity to hydrogen, and the efficiency of solar heat to hydrogen is 49.75%. It exhibits high conversion efficiency of sunlight to hydrogen when compared with analogous hydrogen production systems. These outcomes firmly establish the potential of blended nanofluid filters within hydrogen production systems, offering a feasible pathway toward achieving comprehensive solar-driven hydrogen production.