The transition to sustainable materials and eco‐efficient processes in commercial electronics is a driving force in developing green electronics. Iron‐catalyzed laser‐induced graphitization (IC‐LIG) has been demonstrated as a promising approach for rendering biomaterials electrically conductive. To optimize the IC‐LIG process and fully exploit its potential for future green electronics, it is crucial to gain deeper insights into its catalyzation mechanism and structural evolution. However, this is challenging due to the rapid nature of the laser‐induced graphitization process. Therefore, multiscale preparation techniques, including ultramicrotomy of the cross‐sectional transition zone from precursor to fully graphitized IC‐LIG electrode, are employed to virtually freeze the IC‐LIG process in time. Complementary characterization is performed to generate a 3D model that integrates nanoscale findings within a mesoscopic framework. This enabled tracing the growth and migration behavior of catalytic iron nanoparticles and their role during the catalytic laser‐graphitization process. A three‐layered arrangement of the IC‐LIG electrode is identified including a highly graphitized top layer with an interplanar spacing of 0.343 nm. The middle layer contained γ‐iron nanoparticles encapsulated in graphitic shells. A comparison with catalyst‐free laser graphitization approaches highlights the unique opportunities that IC‐LIG offers and discuss potential applications in energy storage devices, catalysts, sensors, and beyond.

The nanowatt‐level power density of current biobased piezoelectric energy harvesters restricts their applicative potential for the efficient conversion of biomechanical energy. A high‐performing, fully renewable piezoelectric device incorporating green piezo‐active Rochelle salt in a laser‐drilled wood template is demonstrated to form ordered crystal pillar arrays by melt crystallization. Investigating the effect of different crystal pillar configurations on the piezoelectric response, a shearing design (45°‐oriented pillars) shows potential of up to 30 V and a current of 4 µA – corresponding to a 10‐fold power increase compared to single‐crystalline Rochelle salt. A concept of direct laser graphitization on the crystal surfaces are demonstrated using a fully renewable ink to create electrodes of low resistance (36 Ω sq ⁻¹ ). The entire device can be disassembled, fully recycled, and reused. This nanogenerator outperforms state‐of‐the‐art biobased ones and competes with conventional lead‐based devices in power generation while showing a significantly lower environmental footprint, as indicated by life‐cycle assessment.

We demonstrate the autonomous synthesis of iron (hydr)oxide (green rust, magnetite, and lepidocrocite) nanoparticles by precipitating iron(II) ions using hydroxide ions generated in situ with the methylene glycol-sulfite (MGS) reaction, a pH-clock. We show that the nature of the products can be predetermined by tuning the initial iron(II) concentration.

We describe a preliminary investigation of the dissolution dynamics of zinc oxide nanoparticles in the presence of cyclic esters (δ-gluconolactone and propanesultone) as slow acid generators. The particles dissolution is monitored by means of turbidimetry and correlated with the evolution of pH over time. The results could be of interest for the design of chemically programmable colloidal systems.

The methylene glycol–sulfite clock reaction enables the time-programmable synthesis of silver nanoparticles with tailorable size and monodispersity.

Iron‐catalyzed laser‐induced graphitization (IC‐LIG) represents an eco‐efficient alternative to traditional carbon electrode manufacturing. Combining a bio‐based tannic acid–iron precursor ink with CO₂ laser treatment results in sheet resistance of 23.59 ± 1.2Ω □⁻¹ on renewable substrates. Varying the tannic‐acid‐to‐iron ratio (TA:Fe), the rheology of the precursor ink can be tuned, enabling versatile application techniques, including spray coating, screen printing, and direct‐ink‐writing (DIW). Subsequent laser‐treatment enables the formation of functional IC‐LIG electrodes for all application methods, while even thick DIW‐printed layers (260 µm) result in complex, conductive electrode patterns. Laser post‐treatment expands design possibilities by locally tuning iron phases, such as converting γ‐iron to magnetite. The unidirectional laser‐treatment results in a layered arrangement, forming a multilayer electrode with a highly graphitized top layer serving as a current collector substitute, and an underlying composite of iron‐rich nanoparticles embedded in a porous graphitic foam, acting as a hybrid electrode. Electrochemical analysis reveals double‐layer capacitor behavior at low TA:Fe ratios, while higher ratios demonstrate increased redox activity and pseudo‐capacitive characteristics. Achieving stable capacities of 15 mF cm⁻² with a 1 M NaCl electrolyte over 5000 cycles underscores the potential of IC‐LIG electrodes as a sustainable solution for advanced energy storage devices and beyond.