MXene, a new series of 2D material, has been steadily advancing its applications to a variety of fields, such as catalysis, supercapacitor, molecular separation, electromagnetic wave interference shielding. This work reports a carefully designed aqueous droplet light heating system along with a thorough mathematical procedure, which combined leads to a precise determination of internal light-to-heat conversion efficiency of a variety of nanomaterials. The internal light-to-heat conversion efficiency of MXene, more specifically TiC, was measured to be 100%, indicating a perfect energy conversion. Furthermore, a self-floating MXene thin membrane was prepared by simple vacuum filtration and the membrane, in the presence of a rationally chosen heat barrier, produced a light-to-water-evaporation efficiency of 84% under one sun irradiation, which is among the state of art energy efficiency for similar photothermal evaporation system. The outstanding internal light-to-heat conversion efficiency and great light-to-water evaporation efficiency reported in this work suggest that MXene is a very promising light-to-heat conversion material and thus deserves more research attention toward practical applications.

Self‐healing hydrophobic light‐to‐heat conversion membranes for interfacial solar heating are fabricated by deposition of light‐to‐heat conversion material of polypyrrole onto a porous stainless‐steel mesh, followed by hydrophobic fluoroalkylsilane modification. The mesh‐based membranes spontaneously stay at the water–air interface, collect and convert solar light into heat, and locally heat only the water surface for enhanced evaporation.

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The Earth's atmosphere holds approximately 12 900 billion tons of fresh water distributed all over the world with fast replenishment. Atmospheric water harvesting is emerging as a promising strategy for clean water production in arid regions, land-locked areas, and remote communities. The water vapor sorbent is the key component for atmospheric water harvesting devices based on absorbing-releasing process. In this work, a flexible hybrid photothermal water sorbent composed of deliquescent salt and hydrogel was rationally fabricated. It possesses superior water sorption capacity even in low humidity air thanks to the deliquescent salt and maintains a solid form after it sorbs a large amount of water owing to the hydrogel platform. The harvested water could be easily released under regular sunlight via the photothermal effect, and it can be directly reused without noticeable capacity fading. An "easy-to-assemble-at-household" prototype device with 35 g of the dry hydrogel was tested outdoors under field conditions and delivered 20 g of fresh water within 2.5 h under natural sunlight. It is estimated that the material cost of making such a device to supply minimum daily water consumption for an adult (i.e., 3 kg) is only $3.20 (USD). This type of atmospheric water generator (AWG) is cheap and affordable, works perfectly with a broad range of humidity, does not need any electricity, and thus is especially suitable for clean water production in remote areas.

Salinity-gradient is emerging as one of the promising renewable energy sources but its energy conversion is severely limited by unsatisfactory performance of available semipermeable membranes. Recently, nanoconfined channels, as osmotic conduits, have shown superior energy conversion performance to conventional technologies. Here, ion selective nanochannels in lamellar Ti3C2T x MXene membranes are reported for efficient osmotic power harvesting. These subnanometer channels in the Ti3C2T x membranes enable cation-selective passage, assisted with tailored surface terminal groups, under salinity gradient. A record-high output power density of 21 W·m–2 at room temperature with an energy conversion efficiency of up to 40.6% is achieved by controlled surface charges at a 1000-fold salinity gradient. In addition, due to thermal regulation of surface charges and ionic mobility, the MXene membrane produces a large thermal enhancement at 331 K, yielding a power density of up to 54 W·m–2. The MXene lamellar structure, coupled with its scalability and chemical tunability, may be an important platform for high-performance osmotic power generators.

Clean water shortage has long been a challenge in remote and landlocked communities especially for the impoverished. Atmospheric water is now considered as an unconventional but accessible fresh water source and sorption-based atmospheric water generator (AWG) has been successfully demonstrated a reliable way of harvesting atmospheric water. The water vapor sorbents with high water uptake capacity and especially fast vapor sorption/desorption kinetics have become the bottleneck to a desirable clean water productivity in AWG. In this work, we developed a new nano vapor sorbent composed of a nano carbon hollow capsule with LiCl inside the void core. The sorbent can capture water vapor from ambient air as much as 100% of its own weight under RH 60% within 3 hours and quickly release the sorbed water within just half hour under 1 kW/m 2 sunlight irradiation. A batch-mode AWG device was able to conduct 3 sorption/desorption cycles within 10 hours during one day test in the outdoor condition and produced 1.6 kgwater/kgsorbent. A prototype of continuous AWG device was designed, fabricated, and successfully demonstrated, hinting a possible way of large-scale deployment of AWG for practical purposes.

The energy shortage and clean water scarcity are two key challenges for global sustainable development. Near half of the total global water withdrawals is consumed by power generation plants while water desalination consumes lots of electricity. Here, we demonstrate a photovoltaics-membrane distillation (PV-MD) device that can stably produce clean water (>1.64 kg·m −2 ·h −1 ) from seawater while simultaneously having uncompromised electricity generation performance (>11%) under one Sun irradiation. Its high clean water production rate is realized by constructing multi stage membrane distillation (MSMD) device at the backside of the solar cell to recycle the latent heat of water vapor condensation in each distillation stage. This composite device can significantly reduce capital investment costs by sharing the same land and the same mounting system and thus represents a potential possibility to transform an electricity power plant from otherwise a water consumer to a fresh water producer.

Intracardiac leiomyomatosis is rare but has been increasingly reported in recent years. Owing to its rarity, intracardiac leiomyomatosis has been reported only as isolated case reports and case series. This disorder is thought to be underestimated and easily overlooked in the clinic, while it is dangerous owing to the risk of sudden death caused by total outflow tract obstruction. We performed an electronic literature search for intracardiac leiomyomatosis and identified 194 cases that were reported in English from 1974 (the first reported case) to September 2012. Our aim is to provide a detailed and comprehensive review of the clinical presentation, diagnosis, histopathological characterization, treatment and prognosis of this disorder. According to our analysis, intracardiac leiomyomatosis is most common in the fifth decade, and the mean age of detection is ~50 years. Most patients had undergone previous hysterectomy/myomectomy or had a coexisting uterine leiomyoma when admitted. The most common clinical presentations were dyspnoea, syncope, oedema of the lower extremities and palpitation. Transoesophageal echocardiography, computed tomography and magnetic resonance imaging are helpful in the preoperative diagnosis and to guide the surgical management. Complete removal guarantees an excellent outcome, with no recurrence or postoperative death, while incomplete removal leads to recurrence in one-third of patients. Anti-oestrogen therapy is not imperative after incomplete removal owing to its inability to prevent recurrence.