Developing high‐performance and cost‐effective bifunctional electrocatalysts for large‐scale water electrolysis is desirable but remains a significant challenge. Most existing nano‐ and micro‐structured electrocatalysts require complex synthetic procedures, making scale‐up highly challenging. Here, a heterogeneous Ni2P‐Fe2P microsheet is synthesized by directly soaking Ni foam in hydrochloric acid and an iron nitrate solution, followed by phosphidation. Benefiting from high intrinsic activity, abundant active sites, and a superior transfer coefficient, this self‐supported Ni2P‐Fe2P electrocatalyst shows superb catalytic activity toward overall water splitting, requiring low voltages of 1.682 and 1.865 V to attain current densities of 100 and 500 mA cm−2 in 1 m KOH, respectively. Such catalytic performance is superior to the benchmark IrO2 || Pt/C pair and also places this electrocatalyst among the best bifunctional catalysts reported thus far. Furthermore, its enhanced corrosion resistance and hydrophilic surface make it suitable for seawater splitting. It is able to achieve current densities of 100 and 500 mA cm−2 in 1 m KOH seawater at voltages of 1.811 and 2.004 V, respectively, which, together with its robust durability, demonstrates its great potential for realistic seawater electrolysis. This work presents a general and economic approach toward the fabrication of heterogeneous metallic phosphide catalysts for water/seawater electrocatalysis.

A robust oxygen-evolving electrocatalyst for high-performance seawater splitting was developed using a cost-effective and industrially compatible method.

Genetic modification plays a vital role in breeding new crops with excellent traits. Almost all the current genetic modification methods require regeneration from tissue culture, involving complicated, long and laborious processes. In particular, many crop species such as cotton are difficult to regenerate. Here, we report a novel transformation platform technology, pollen magnetofection, to directly produce transgenic seeds without regeneration. In this system, exogenous DNA loaded with magnetic nanoparticles was delivered into pollen in the presence of a magnetic field. Through pollination with magnetofected pollen, transgenic plants were successfully generated from transformed seeds. Exogenous DNA was successfully integrated into the genome, effectively expressed and stably inherited in the offspring. Our system is culture-free and genotype independent. In addition, it is simple, fast and capable of multi-gene transformation. We envision that pollen magnetofection can transform almost all crops, greatly facilitating breeding processes of new varieties of transgenic crops.

The current simple nanofluid flooding method for tertiary or enhanced oil recovery is inefficient, especially when used with low nanoparticle concentration. We have designed and produced a nanofluid of graphene-based amphiphilic nanosheets that is very effective at low concentration. Our nanosheets spontaneously approached the oil-water interface and reduced the interfacial tension in a saline environment (4 wt % NaCl and 1 wt % CaCl 2 ), regardless of the solid surface wettability. A climbing film appeared and grew at moderate hydrodynamic condition to encapsulate the oil phase. With strong hydrodynamic power input, a solid-like interfacial film formed and was able to return to its original form even after being seriously disturbed. The film rapidly separated oil and water phases for slug-like oil displacement. The unique behavior of our nanosheet nanofluid tripled the best performance of conventional nanofluid flooding methods under similar conditions. nanofluid flooding | amphiphilic Janus nanosheets | enhanced oil recovery | climbing film | interfacial film F inding economically viable and environmentally friendly methods to extract the huge amount of residual oil after primary and secondary recovery remains challenging for the oil and gas industry and is also of significant importance in efforts to satisfy the world's increasing energy demand. Nanofluid flooding as an alternative tertiary oil recovery method has been recently reported (1-5). Obviously, simple nanofluid flooding (containing only nanoparticles) at low concentration (0.01 wt % or less) shows the greatest potential from the environmental and economic perspective. Several corresponding oil displacement mechanisms have also been introduced, including reduction of oil-water interfacial tension (6, 7), alteration of rock surface wettability (8-10), and generation of structural disjoining pressure (11-13). However, the oil recovery factor is below 5% with 0.01% nanoparticle loading in core flooding tests in a saline environment (2 wt % or higher NaCl content). Here we show that an oil recovery factor of 15.2% is achieved by using a simple nanofluid of graphene-based Janus amphiphilic nanosheets. To our knowledge, this is the first report of applying nanofluid of amphiphilic Janus two-dimensional materials in tertiary or enhanced oil recovery. We found that in a saline environment, the nanosheets spontaneously approach the oil-water interface, reducing the interfacial tension. A climbing film emerges and encapsulates the oil phase and may carry it forward. Furthermore, we found that a solid-like film forms with strong hydrodynamic power. The film rapidly separates oil and water for slug-like oil displacement. Even though there are ways to achieve 20% enhanced recovery by complicated alkali/surfactant/polymer flooding (14) or by surfactants with added nanoparticles (5), the necessary concentrations of the chemicals and nanoparticles are much higher than 0.01 wt %. Our results provide a nanofluid flooding method for tertiary oil recovery that is compar...

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Amorphous NiFe LDH nanosheets were decorated on nickel phosphide nanoarrays to form a 3D core–shell electrocatalyst for efficient water oxidation.