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Pb(II) has long been associated with lone pair activity and is often substituted in alkali earth metal borates to create new nonlinear optical (NLO) materials with enhanced second harmonic generation (SHG) capabilities. However, large enhancement in isomorphic Pb-free analogues is rare. Here we report a new NLO material Pb2Ba3(BO3)3Cl with a phase-matching SHG response approximately 3.2× that of KDP and 6× higher than its isomorphic compound Ba5(BO3)3Cl. We show that the enhanced SHG response originates from a unique edge-sharing connection between lead-oxygen polyhedra and boron-oxygen groups, making the dielectric susceptibility more easily affected by the external electric field of an incident photon. This understanding provides a route to identify systems that would benefit from SHG-active cation substitution in isomorphic structures that exhibit weak or null SHG responses.

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An incommensurate modulated antiferroelectric phase is a key part of ideal candidate materials for the next generation of dielectric ceramics with excellent energy storage properties. However, there is less research carried out when considering its relatively low polarization response. Here, the incommensurate phase is modulated by stabilizing the antiferroelectric phase and the energy storage performance of the incommensurate phase under ultrahigh electric field is studied. The tape‐casting method is applied to construct dense and thin ceramics. La3+ doping induces a room‐temperature incommensurate antiferroelectric orthorhombic matrix. With little Cd2+, the extremely superior energy storage performances arose as follows: when 0.03, the recoverable energy storage density reaches ≈19.3 J cm‐3, accompanying an ultrahigh energy storage efficiency of ≈91% (870 kV cm‐1); also, a giant discharge energy density of ≈15.4 J cm‐3 emerges during actual operation. In situ observations demonstrate that these superior energy storage properties originate from the phase transition from the incommensurate antiferroelectric orthorhombic phase to the induced rhombohedral relaxor ferroelectric one. The adjustable incommensurate period affects the depolarization response. The revealed phase‐transition mechanism enriches the existing antiferroelectric–ferroelectric transition. Attention to the incommensurate phase can provide a reference for the selection of the next generation of high‐performance antiferroelectric materials.

Mechanical energy driven wireless charging technology has recently gained increasing attention. High-performance potassium sodium niobate (KNN) based texture ceramics and its potential application on energy harvesting device are the first...

A new noncentrosymmetric borophosphate, Na(3)Cd(3)B(PO(4))(4), has been successfully synthesized by conventional solid state reaction for the first time. It crystallizes in the orthorhombic space group Pmc2(1) with unit cell parameters of a = 13.6854(3) Å, b = 5.3346(11) Å, c = 18.2169(4) Å, and Z = 4. Na(3)Cd(3)B(PO(4))(4) features zero-dimensional [B(PO(4))(4)](9-) anion units with Cd(2+) and Na(+)/Cd(2+) cations located around them, in which the BO(4) tetrahedron is surrounded by four PO(4) tetrahedra by sharing the vertexes of O atoms. Second harmonic generation (SHG) measurements show that Na(3)Cd(3)B(PO(4))(4) exhibits a SHG response 1.1 times larger than that of KH(2)PO(4) (KDP) and is phase matchable.

Borate not graphene: The [B6O12]∞(6-) single borate layer is a graphene-like layer (see figure). The weak Na(+)-Br(Cl)(-) ionic connection between the layers leads to the layer cleavage, and difficulty of the block crystal growth.

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