A laser‐based patterning technique—compatible with flexible, temperature‐sensitive substrates—for the production of large area reduced graphene oxide micromesh (rGOMM) electrodes is presented. The mesh patterning can be accurately controlled in order to significantly enhance the electrode transparency, with a subsequent slight increase in the sheet resistance, and therefore improve the tradeoff between transparency and conductivity of reduced graphene oxide (rGO) layers. In particular, rGO films with an initial transparency of ≈20% are patterned, resulting in rGOMMs films with a ≈59% transmittance and a sheet resistance of ≈565 Ω sq−1, that is significantly lower than the resistance of ≈780 Ω sq−1, exhibited by the pristine rGO films at the same transparency. As a proof‐of‐concept application, rGOMMs are used as the transparent electrodes in flexible organic photovoltaic (OPV) devices, achieving power conversion efficiency of 3.05%, the highest ever reported for flexible OPV devices incorporating solution‐processed graphene‐based electrodes. The controllable and highly reproducible laser‐induced patterning of rGO hold enormous promise for both rigid and flexible large‐scale organic electronic devices, eliminating the lag between graphene‐based and indium–tin oxide electrodes, while providing conductivity and transparency tunability for next generation flexible electronics.

Solar-energy harvesting through photovoltaic (PV) conversion is the most promising technology for long-term renewable energy production. At the same time, significant progress has been made in the development of energy-storage (ES) systems, which are essential components within the cycle of energy generation, transmission, and usage. Toward commercial applications, the enhancement of the performance and competitiveness of PV and ES systems requires the adoption of precise, but simple and low-cost manufacturing solutions, compatible with large-scale and high-throughput production lines. Photonic processes enable cost-efficient, noncontact, highly precise, and selective engineering of materials via photothermal, photochemical, or photophysical routes. Laser-based processes, in particular, provide access to a plethora of processing parameters that can be tuned with a remarkably high degree of precision to enable innovative processing routes that cannot be attained by conventional approaches. The focus here is on the application of advanced light-driven approaches for the fabrication, as well as the synthesis, of materials and components relevant to PV and ES systems. Besides presenting recent advances on recent achievements, the existing limitations are outlined and future possibilities and emerging prospects discussed.

A facile, low-temperature precipitation-based method is utilized for the synthesis of ultra-thin and highly uniform cesium lead bromide perovskite nanowires (NWs). The reactions facilitate the NWs' crystalline nature over micron-size lengths, while they impart tailored nanowire widths that range from the quantum confinement regime (∼7 nm) down to 2.6 nm. This colloidal synthesis approach is the first of its kind that is carried out on the work-bench, without demanding chemical synthesis equipment. Importantly, the NWs' photoluminescence is shown to improve over time, with no requirement for tedious post-synthesis surface treatment.

The excitation of plasmonic nanoparticles by ultrashort laser pulses sets in motion a complex ultrafast relaxation process involving the gradual re-equilibration of the system's electron gas, lattice and environment. One of the major hurdles in studying these processes is the lack of direct measurements of the dynamic temperature evolution

Enhancement of the stability of bulk heterojunction (BHJ) organic photovoltaic (OPV) devices is reported by the addition of surfactant-free aluminum (Al) nanoparticles (NPs) into the photoactive layer. The universality of the effect is demonstrated for two different BHJ systems, namely, the well-studied poly(3-hexylthiophene-2,5-diyl):phenyl-C61-butyric acid methyl ester (P3HT:PCBM) as well as the high efficient poly[N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)]:[6,6]-phenyl-C71-butyric acid methyl ester (PCDTBT:PC71BM). It is shown that the lifetime of the devices with Al NPs, operating under continuous one-sun illumination in ambient conditions, is more than three times longer compared to the reference devices. Using complementary analytical techniques for in situ studies, we have explored the underlying mechanisms behind the observed stability improvement in the case of the P3HT:PCBM system. In particular, laser-induced fluorescence (LIF), photoluminescence decay and Fourier transform infrared (FTIR) spectroscopy experiments were performed and complemented with device degradation electrical measurements. It is found that the embedded Al NPs act as performance stabilizers, giving rise to enhanced structural stability of the active blend. Furthermore, it is revealed that the observed improvement can also be ascribed to NP-mediated mitigation of the photo-oxidation effect. This study addresses a major issue in OPV devices, that is, photoinduced stability, indicating that the exploitation of Al NPs could be a successful approach toward fabricating OPVs exhibiting long-term operating lifetimes.

A novel top-down and universal optical technique for the effective decoration of two-dimensional (2D) nanosheets (NS), graphene oxide (GO), boron nitride (BN) and tungsten disulfide (WS2), with noble metallic nanoparticles (NPs) is reported.

We demonstrate a facile, low-cost and room-temperature method of anion exchange in cesium lead bromide nanocrystals (CsPbBr3 NCs), embedded into a polymer matrix.

Since the isolation of free standing graphene in 2004, graphene research has experienced a phenomenal growth.