Photocatalysis is an effective way to utilize solar energy to produce hydrogen from water. Au/TiO₂ nanoparticles (NPs) have a better performance in photocatalytic hydrogen generation because of the localized surface plasmon resonance (LSPR) effect of Au/TiO₂ NPs. In the photocatalytic hydrogen generation experiments, it was found that light intensity plays a key role in the photocatalytic reaction rate of Au/TiO₂ NPs. At a light intensity of 0–7 kW/m², the reaction rate has a super-linear law dependence on the light intensity (Rate ∝ Intensityⁿ, with n > 1). However, at a light intensity of 7–9 kW/m², the dependency becomes sub-linear (n < 1). This means that the increase rate of photocatalytic rate is smaller than that of light intensity when the light intensity exceeds 7 kW/m². In addition, the finite element method (FEM) was utilized to further elucidate the role of light intensity by calculating the absorption power and nearfield intensity mapping of a Au/TiO₂ nanoparticle. The variation trend of the calculated total absorption power agrees with the photocatalytic experimental results for different light intensities. These results shed light on the utilization of concentrated solar photocatalysis to increase the solar-to-hydrogen performance of Au/TiO₂ NPs.

光催化是利用太阳能从水中产生氢的有效方法。由于Au / TiO ₂ NP的局部表面等离子体共振（LSPR）效应，Au / TiO ₂纳米颗粒（NPs）在光催化制氢方面具有更好的性能。在光催化制氢实验中，发现光强度在Au / TiO ₂ NPs的光催化反应速率中起关键作用。在0-7 kW / m ²的光强度下，反应速率具有与光强度相关的超线性定律（速率∝强度ⁿ，n  > 1）。但是，在7–9 kW / m ²的光强度下，相关性变为次线性（n <1）。这意味着当光强度超过7kW / m ²时，光催化速率的增加速率小于光强度的增加速率。另外，通过计算Au / TiO ₂纳米粒子的吸收功率和近场强度图，利用有限元方法（FEM）进一步阐明了光强度的作用。对于不同的光强度，计算出的总吸收功率的变化趋势与光催化实验结果一致。这些结果揭示了利用集中的太阳能光催化来提高Au / TiO ₂ NPs的太阳能转化性能。