Traditional energy-integration X-ray imaging systems rely on total X-ray intensity for image contrast, ignoring energy-specific information. Recently developed multilayer stacked scintillators have enabled multispectral, large-area flat-panel X-ray imaging (FPXI), enhancing material discrimination capabilities. However, increased layering can lead to mutual excitation, which may affect the accurate discrimination of X-ray energy. This issue is tackled by proposing a novel design strategy utilizing rare earth ions doped quantum-cutting scintillators as the top layer. These scintillators create new luminescence centers via energy transfer, resulting in a significantly larger absorption-emission shift, as well as the potential to double the photoluminescence quantum yield (PLQY) and enhance light output. To verify this concept, a three-layer stacked scintillator detector is developed using ytterbium ions (Yb