This article reviews recent developments in laser direct-write addition (LDW+) processes for printing complex materials. Various applications, ranging from small-scale energy storage and generation devices to tissue engineering, require the ability to deposit precise patterns of multicomponent and multiphase materials without degrading desirable properties such as porosity, homogeneity, or biological activity. Structurally complex inorganic materials for the successful fabrication of alkaline and lithium-based microbatteries, micro-ultracapacitors, and dye-sensitized micro solar cells are shown on various low-processing-temperature and flexible substrates using LDW+. In particular, the ability to deposit thick layers while maintaining pattern integrity allows devices produced in this manner to exhibit higher energy densities per unit area than can be achieved by traditional thin-film techniques. We then focus on more complex systems of living and biologically active materials. Patterns of biomaterials such as proteins, DNA, and even living cells can be printed using LDW+ with high spatial and volumetric resolution on the order of a picoliter or less, without compromising the viability of these delicate structures. These results provide for highly selective sensor arrays or cell seeding for tissue engineering. Finally, we review recent work on LDW+ of entire semiconductor circuits, showing the broad range of applications this technique enables.

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We demonstrate a method for controlled p-doping of the halide perovskite surface using molecular dopants, resulting in reduced non-radiative recombination losses and improved device performance.

The global demand for clean and safe water will continue to grow well into the 21st century. Moving forward, the lack of access to clean water, which threatens human health and strains precious energy resources, will worsen as the climate changes. Therefore, future innovations that produce potable water from contaminated sources must be sustainable. Inspired by nature, a solar absorber gel (SAG) is developed to purify water from contaminated sources using only natural sunlight. The SAG is composed of an elastic thermoresponsive poly(N‐isopropylacrylamide) (PNIPAm) hydrogel, a photothermal polydopamine (PDA) layer, and a sodium alginate (SA) network. Production of the SAG is facile; all processing is aqueous‐based and occurs at room temperature. Remarkably, the SAG can purify water from various harmful reservoirs containing small molecules, oils, metals, and pathogens, using only sunlight. The SAG relies on solar energy to drive a hydrophilic/hydrophobic phase transformation at the lower critical solution temperature. Since the purification mechanism does not require water evaporation, an energy‐intensive process, the passive solar water‐purification rate is the highest reported. This discovery can be transformative in the sustainable production of clean water to improve the quality of human life.

We report a new H x CrS 2 -based crystalline/amorphous layered material synthesized by soft chemical methods. We study the structural nature and composition of this material with atomic resolution scanning transmission electron microscopy (STEM), revealing a complex structure consisting of alternating layers of amorphous and crystalline lamellae. Furthermore, the magnetic properties show evidence for increased magnetic frustration compared to the parent compound NaCrS 2 . Finally, we show that this material can be exfoliated, thus providing a facile synthesis method for chromium-sulfide-based ultrathin layers. The material reported herein can not only be a source of new thin TMD-related sheets for potential application in catalysis but also be of interest for realizing new 2D magnetic materials.