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In the development of perovskite solar cells, a new version of Don Quixote is needed if scientists are to keep on seeking the most celebrated works of literature, according to the evaluation criterion of ‘THE FIRST’ and ‘THE BEST’.

The lead-free double perovskite has been proven to be one of the promising alternatives to solve the stability and toxicity problems of lead-based organic−inorganic hybrid perovskite solar cells. Here, highquality Cs 2 AgBiBr 6 double perovskite films with large grains and smooth surface have been prepared through a sequential-vapor-deposition method, and a low-cost and eco-friendly Cu 2 O film with a suitable energy level and good electrical properties was prepared as an efficient hole transport layer by vacuum vapor deposition for the first time. The Cu 2 O-based devices achieve a champion power conversion efficiency increasing from 1.03 to 1.52% and an enhancement of photovoltage from 1.083 to 1.198 V compared with their organic counterparts. More importantly, the Cu 2 Obased devices have excellent stability; they maintained the initial 96% efficiency under environmental conditions after 33 days of unpackaged storage. These results also point out the direction for the further development of these new promising perovskite solar cells.

Diatoms are one major group of algae in oceans that accounts almost half of marine primary food production and have also been identified as a promising candidate for biofuel production for their high level accumulation of lipids. They have gained increasingly attention for their potential applications in pharmaceuticals, cosmetics, nutrient supplements, and biofuels. This review aims to summarize the recent advances in diatom lipid study. Chemical structures and bioactivities of different lipid classes are discussed with a focus on valuable lipids such as fatty acids, polar lipids, steroids, and oxylipins from various diatoms species. Further, current extraction and fractionation approaches are compared and recent analytical techniques and methods are also reviewed with an emphasis on lipid class composition and fatty acid profiling. Biosynthetic pathways and key catalyzing enzymes are illustrated for a better understanding of fatty acid metabolism. Past engineering attempts toward generating appropriate diatom strains for lipid production are discussed with examples using mutagenesis, environmental stimulants, and genetic modification methods. Some possible future directions and applications of diatom-derived lipids are also proposed.

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Marine diatoms have recently gained much attention as they are expected to be a promising resource for sustainable production of bioactive compounds such as carotenoids and biofuels as a future clean energy solution. To develop photosynthetic cell factories, it is important to improve diatoms for value-added products. In this study, we utilized UVC radiation to induce mutations in the marine diatom Phaeodactylum tricornutum and screened strains with enhanced accumulation of neutral lipids and carotenoids. Adaptive laboratory evolution (ALE) was also used in parallel to develop altered phenotypic and biological functions in P. tricornutum and it was reported for the first time that ALE was successfully applied on diatoms for the enhancement of growth performance and productivity of value-added carotenoids to date. Liquid chromatography-mass spectrometry (LC-MS) was utilized to study the composition of major pigments in the wild type P. tricornutum, UV mutants and ALE strains. UVC radiated strains exhibited higher accumulation of fucoxanthin as well as neutral lipids compared to their wild type counterpart. In addition to UV mutagenesis, P. tricornutum strains developed by ALE also yielded enhanced biomass production and fucoxanthin accumulation under combined red and blue light. In short, both UV mutagenesis and ALE appeared as an effective approach to developing desired phenotypes in the marine diatoms via electromagnetic radiation-induced oxidative stress.

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Organic–inorganic lead halide perovskites solar cells (PSCs) show great potential in the photovoltaic system, reaching overall power conversion efficiencies (PCE) up to 25.2%. The rapid increase of PCE in PSCs has made them the rising star of the photovoltaics world, with great interest to the academic community. Long‐term stability under working environments remains a significant challenge for the commercialization of PSCs, particularly those using inorganic–organic halide lead perovskite absorbers. In this regard, only the devices that can maintain long‐term stability under conditions of temperature, humidity, and UV irradiation can be called stable solar cells. This Review highlights the sources for the chemical instability problems in conventional CH3NH3PbI3‐based perovskite solar cells from humidity instability, phase instability, thermal instability, and ion migration. In pursuit of highly stable PSCs, this article also discusses the strategies to stabilize PSCs through both external and internal aspects without sacrificing the PCE, specifically including additive engineering with surface passivation and composition engineering.