The effective separation and migration of photogenerated charge carriers in bulk and on the surface of photocatalysts will significantly promote photocatalytic efficiency. However, the synchronous regulation of photocharges on both counts is challenging. Herein, the simultaneous separation of bulk and surface photocharges is conducted to enhance photocatalytic activity by coupling the surface defects and lattice engineering of bismuth oxybromide. The depth-modulated Bi₅O₇Br ultrathin nanosheets with an abundance of bismuth in the crystal structure increased the internal electric field, which propelled the separation and migration of photocharges from bulk to the surface. Creation of oxygen vacancies (OVs) on the nanosheet surface forms local electric fields, which can stimulate the migration of charges to active sites on the catalyst surface. Therefore, the OV-assembled Bi₅O₇Br nanosheets demonstrated enhanced photocatalytic degradation efficiency under simulated solar-light illumination. This study proved the possibility of charge governing via electric field modulation based on an integrated strategy.

Although tremendous efforts have been paid on electrocatalysts toward efficient electrochemical hydrogen generation, breakthrough is still highly needed in the design and synthesis of wonderful non-precious-metal electrocatalyst. Herein, a nanovilli Ni₂P electrode, which with superaerophobic and superhydropholic can significantly facilitate the mass and electron transfer was constructed via a facial morphology control strategy. Meanwhile, the substitution of sluggish oxygen evolution with urea oxidation, lowering the two-electrode cell voltage to only 1.48 volts to achieve a current density of 10 mA·cm⁻². Thus, the as-constructed electrode achieves the operation of hydrogen generation by an AA battery. This work sheds new light on the exploration of other high-efficient electrocatalysts for hydrogen generation by using intermittent clean energy.