X-ray diffraction analysis of polycrystals (PXRD) is crucial for examining the correlation between the crystalline structure and porosity and, consequently, its functionality. The organized packing of atoms and molecules dictates the size, shape, and connectivity of the void spaces that form, and this relationship is essential in material science and engineering. The Powder X-ray Diffraction technique using synchrotron radiation (SR-PXRD) offers advantages such as high photon flux, low-divergence X-ray beams, and adjustable energy levels, thereby minimizing instrumental effects on peak profiles and enabling high-resolution analyses. The PAINEIRA beamline is a facility dedicated to the X-ray diffraction characterization of polycrystalline materials in operation at the Brazilian synchrotron radiation (SR) facility – SIRIUS. Its optical layout optimizes the high photon brightness of fourth-generation synchrotron light from an undulator [1]. The benefits of using SR-XRD for characterizing polycrystalline materials at PAINEIRA extend beyond high resolution and signal-to-noise ratio. SR-XRD experiments can be combined with appropriate sample environments, fluid-handling systems, and large angular resolution and fast detectors to facilitate in situ and operando experiments that reveal transient crystalline phases or structures responsible for the performance of functional materials [2]. The beamline was designed to be efficient and flexible for data acquisition, providing high angular resolution with a multi-analyzer crystal detector (MAC) and/or a fast-area detector (arc detector, PIMEGAE 450D). Furthermore, PAINEIRA will operate in high-throughput mode, supported by an automated system that includes a sample magazine, robotic arms, sensors, and experimental management software for fully automated remote data acquisition [1]. Automated experiments under variable temperature conditions will also be available [2]. In this presentation, I will provide an overview of the PAINEIRA beamline, primarily focusing on the mechanical, automated, and computational tools [3] that enhance efficiency and create a user-friendly environment for powder X-ray diffraction experiments. Subsequently, apparatus for in situ and operando experiments, especially developed for catalysis, solar cells, and batteries, will also be presented. Ultimately, it will be demonstrated how this specialized synchrotron tool can investigate fundamental material properties at the atomic level and correlate them with their corresponding functions. 
[1] Estrada, F. R., et al. (2022) J. Phys.: Conf. Series 2380, 012033. [2] Ferreira, A. I., et al. (2025) J. Phys.: Conf. Series 3010, 012147. 
[3] Biondo Neto, J. L., et al. (2025) J. Appl. Cryst. 58, 1061-1067.